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Thi Nguyen H, Choi W, Jeong S, Bae H, Oh S, Cho K. Comprehensive assessment of chlorination disinfection on microplastic-associated biofilms. JOURNAL OF HAZARDOUS MATERIALS 2024; 474:134751. [PMID: 38820748 DOI: 10.1016/j.jhazmat.2024.134751] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/21/2024] [Revised: 05/14/2024] [Accepted: 05/27/2024] [Indexed: 06/02/2024]
Abstract
Chlorination on microplastic (MP) biofilms was comprehensively investigated with respect to disinfection efficiency, morphology, and core microbiome. The experiments were performed under various conditions: i) MP particles; polypropylene (PP) and polystyrene (PS), ii) MP biofilms; Escherichia coli for single-species and river water microorganisms for multiple-species, iii) different chlorine concentrations, and iv) different chlorine exposure periods. As a result, chlorination effectively inactivated the MP biofilm microorganisms. The disinfection efficiency increased with increasing the free chlorination concentration and exposure periods for both single- and multiple-species MP biofilms. The multiple-species MP biofilms were inactivated 1.3-6.0 times less than single-species MP biofilms. In addition, the PP-MP biofilms were more vulnerable to chlorination than the PS-MP biofilms. Morphology analysis verified that chlorination detached most MP biofilms, while a small part still remained. Interestingly, chlorination strongly changed the biofilm microbiome on MPs; the relative abundance of some microbes increased after the chlorination, suggesting they could be regarded as chlorine-resistant bacteria. Some potential pathogens were also remained on the MP particles after the chlorination. Notably, chlorination was effective in inactivating the MP biofilms. Further research should be performed to evaluate the impacts of residual MP biofilms on the environment.
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Affiliation(s)
- Hien Thi Nguyen
- Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Faculty of Environment and Labour Safety, Ton Duc Thang University, Ho Chi Minh City, Vietnam
| | - Woodan Choi
- Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Energy & Environment Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Seongpil Jeong
- Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Energy & Environment Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea
| | - Hyokwan Bae
- Department of Civil, Urban, Earth and Environmental Engineering, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea; Graduate School of Carbon Neutrality, Ulsan National Institute of Science and Technology, 50 UNIST-gil, Eonyang-eup, Ulju-gun, Ulsan 44919, Republic of Korea
| | - Seungdae Oh
- Department of Civil Engineering, College of Engineering, Kyung Hee University, Yongin, Republic of Korea; KHU-KIST Department of Converging Science and Technology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea
| | - Kyungjin Cho
- Center for Water Cycle Research, Korea Institute of Science and Technology, Seoul 02792, Republic of Korea; Division of Energy & Environment Technology, KIST School, Korea University of Science and Technology (UST), Seoul 02792, Republic of Korea; KHU-KIST Department of Converging Science and Technology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul 02447, Republic of Korea.
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Feng C, Li J, Yang W, Chen Z. Study on the inactivation effect and mechanism of EGCG disinfectant on Bacillus subtilis. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124364. [PMID: 38878811 DOI: 10.1016/j.envpol.2024.124364] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/16/2024] [Revised: 06/06/2024] [Accepted: 06/11/2024] [Indexed: 06/22/2024]
Abstract
The widespread use of chlorine-based disinfectants in drinking water treatment has led to the proliferation of chlorine-resistant bacteria and the risk of disinfection byproducts (DBPs), posing a serious threat to public health. This study aims to explore the effectiveness and potential applications of epigallocatechin gallate (EGCG) against chlorine-resistant Bacillus and its spores in water, providing new insights for the control of chlorine-resistant bacteria and improving the biological stability of distribution systems. The inactivation effects of EGCG on Bacillus subtilis (B. subtilis) and its spores were investigated using transmission electron microscopy, ATP measurement, and transcriptome sequencing analysis to determine changes in surface structure, energy metabolism, and gene expression levels, thereby elucidating the inactivation mechanism. The results demonstrate the potential application of EGCG in continuously inhibiting chlorine-resistant B. subtilis in water, effectively improving the biological stability of the distribution system. However, EGCG is not suitable for treating raw water with high spore content and is more suitable as a supplementary disinfectant for processes with strong spore removal capabilities, such as ozone, ultraviolet, or ultrafiltration. EGCG exhibits a disruptive effect on the morphological structure and energy metabolism of B. subtilis and suppresses the synthesis of substances, energy metabolism, and normal operation of the antioxidant system by inhibiting the expression of multiple genes, thereby achieving the inactivation of B. subtilis.
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Affiliation(s)
- Cuimin Feng
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China.
| | - Jing Li
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Weiqi Yang
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
| | - Zexin Chen
- Key Laboratory of Urban Stormwater System and Water Environment, Ministry of Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China; National Demonstration Center for Experimental Water Environment Education, Beijing University of Civil Engineering and Architecture, Beijing, 100044, China
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3
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Wang D, Chen X, Luo J, Shi P, Zhou Q, Li A, Pan Y. Comparison of chlorine and chlorine dioxide disinfection in drinking water: Evaluation of disinfection byproduct formation under equal disinfection efficiency. WATER RESEARCH 2024; 260:121932. [PMID: 38906077 DOI: 10.1016/j.watres.2024.121932] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/18/2024] [Revised: 05/09/2024] [Accepted: 06/11/2024] [Indexed: 06/23/2024]
Abstract
Disinfection efficiency and disinfection byproduct (DBP) formation are two important aspects deserving careful consideration when evaluating different disinfection protocols. However, most of the previous studies on the selection of disinfection methods by comparing DBP formation were carried out under the same initial/residual dose and contact time of different disinfectants, and such a practice may cause overdose or underdose of a certain disinfectant, leading to the inaccurate evaluation of disinfection. In this study, a comprehensive and quantitative comparison of chlorine (Cl2) and chlorine dioxide (ClO2) disinfection was conducted with regard to their DBP formation under equal disinfection efficiency. The microbial inactivation models as well as the Cl2 and ClO2 demand models were developed. On such basis, the integral CT (ICT) values were determined and used as a bridge to connect disinfection efficiency and DBP formation. For 3-log10 and 4-log10 reductions of Pseudomonas aeruginosa, ClO2 had 1.5 and 5.8 times higher inactivation ability than Cl2, respectively. In the premise of equal disinfection efficiency (i.e., the ICT ratios of Cl2 to ClO2 = 1.5 and 5.8), the levels of total organic chlorine, total organic bromine, and total organic halogen formed in the Cl2 disinfection were significantly higher than those formed in the ClO2 disinfection. Among the 35 target aliphatic DBPs, trihalomethanes (THMs) and haloacetic acids (HAAs) were the dominant species formed in both Cl2 and ClO2 disinfection. The total THM levels formed in Cl2 disinfection were 14.6 and 30.3 times higher than those in ClO2 disinfection, respectively. The total HAA levels formed in Cl2 disinfection were 3.5 and 5.4 times higher than those in ClO2 disinfection, respectively. Formation of the target 48 aromatic DBPs was much favored in Cl2 disinfection than that in ClO2 disinfection, and the formation levels was dominated by contact time. This study demonstrated that ClO2 had significant advantages over Cl2, especially at higher microorganism inactivation and lower DBP formation requirements.
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Affiliation(s)
- Dongxiao Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Xueyao Chen
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Jiayi Luo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Peng Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Qing Zhou
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Aimin Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China
| | - Yang Pan
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, Jiangsu 210023, China.
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Reyneke B, Havenga B, Waso-Reyneke M, Khan S, Khan W. Benefits and Challenges of Applying Bacteriophage Biocontrol in the Consumer Water Cycle. Microorganisms 2024; 12:1163. [PMID: 38930545 DOI: 10.3390/microorganisms12061163] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2024] [Revised: 05/31/2024] [Accepted: 06/05/2024] [Indexed: 06/28/2024] Open
Abstract
Bacteria (including disinfection- and antibiotic-resistant bacteria) are abundant in the consumer water cycle, where they may cause disease, and lead to biofouling and infrastructure damage in distributions systems, subsequently resulting in significant economic losses. Bacteriophages and their associated enzymes may then offer a biological control solution for application within the water sector. Lytic bacteriophages are of particular interest as biocontrol agents as their narrow host range can be exploited for the targeted removal of specific bacteria in a designated environment. Bacteriophages can also be used to improve processes such as wastewater treatment, while bacteriophage-derived enzymes can be applied to combat biofouling based on their effectiveness against preformed biofilms. However, the host range, environmental stability, bacteriophage resistance and biosafety risks are some of the factors that need to be considered prior to the large-scale application of these bacterial viruses. Characteristics of bacteriophages that highlight their potential as biocontrol agents are thus outlined in this review, as well as the potential application of bacteriophage biocontrol throughout the consumer water cycle. Additionally, the limitations of bacteriophage biocontrol and corresponding mitigation strategies are outlined, including the use of engineered bacteriophages for improved host ranges, environmental stability and the antimicrobial re-sensitisation of bacteria. Finally, the potential public and environmental risks associated with large-scale bacteriophage biocontrol application are considered, and alternative applications of bacteriophages to enhance the functioning of the consumer water cycle, including their use as water quality or treatment indicators and microbial source tracking markers, are discussed.
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Affiliation(s)
- Brandon Reyneke
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - Benjamin Havenga
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
| | - Monique Waso-Reyneke
- Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa
| | - Sehaam Khan
- Faculty of Health Sciences, University of Johannesburg, P.O. Box 17011, Doornfontein 2028, South Africa
| | - Wesaal Khan
- Department of Microbiology, Faculty of Science, Stellenbosch University, Private Bag X1, Stellenbosch 7602, South Africa
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Zhang J, Ma W, Li Y, Zhong D, Zhou Z, Ma J. The resistance change and stress response mechanisms of chlorine-resistant bacteria under microplastic stress in drinking water distribution system. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 356:124331. [PMID: 38848962 DOI: 10.1016/j.envpol.2024.124331] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2024] [Revised: 05/30/2024] [Accepted: 06/04/2024] [Indexed: 06/09/2024]
Abstract
The presence of both chlorine-resistant bacteria (CRB) and microplastics (MPs) in drinking water distribution systems (DWDS) poses a threat to water quality and human health. However, the risk of CRB bio evolution under the stress of MPs remains unclear. In this study, polypropylene (PP) and polyethylene (PE) were selected to study the adsorption and desorption behavior of sulfamethoxazole (SMX), and it was clear that MPs had the risk of carrying pollutants into DWDS and releasing them. The results of the antibiotic susceptibility test and disinfection experiment confirmed that MPs could enhance the resistance of CRB to antibiotics and disinfectants. Bacteria epigenetic resistance mechanisms were approached from multiple perspectives, including physiological and biochemical characteristics, as well as molecular regulatory networks. When MPs enter DWDS, CRB could attach to the surface of MPs and directly interact with both MPs and the antibiotics they release. This attachment process promoted changes in the composition and content of extracellular polymers (EPS) within cells, enhanced surface hydrophobicity, stimulated oxidative stress function, and notably elevated the relative abundance of certain antibiotic resistance genes (ARGs). This study elucidates the mechanism by which MPs alter the intrinsic properties of CRB, providing valuable insights into the effective avoidance of biological risks to water quality during CRB evolution.
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Affiliation(s)
- Jingna Zhang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Wencheng Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China; Chongqing Research Institute of HIT, Chongqing, 401151, China
| | - Yibing Li
- Central & Southern China Municipal Engineering Design and Research Institute Co., Ltd, Wuhan, 430014, China
| | - Dan Zhong
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China; Chongqing Research Institute of HIT, Chongqing, 401151, China.
| | - Ziyi Zhou
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China
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Wei Y, Wu H, Zhang X, Liang Y, Shi D, Wang L, Li H, Yu H, Yang D, Zhou S, Chen T, Yang Z, Li J, Jin M. Comparative analysis of chlorine-resistant bacteria after chlorination and chloramination in drinking water treatment plants. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:134075. [PMID: 38508114 DOI: 10.1016/j.jhazmat.2024.134075] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/13/2023] [Revised: 02/04/2024] [Accepted: 03/17/2024] [Indexed: 03/22/2024]
Abstract
Chlorine-resistant bacteria (CRB) in drinking water treatment plants (DWTPs) jeopardize water quality and pose a potential risk to human health. However, the specific response of CRB to chlorination and chloramination remains uncharacterized. Therefore, we analyzed 16 S rRNA sequencing data from water samples before and after chlorination and chloramination taken between January and December 2020. Proteobacteria and Firmicutes dominated all finished water samples. After chloramination, Acinetobacter, Pseudomonas, Methylobacterium, Ralstonia, and Sphingomonas were the dominant CRB, whereas Ralstonia, Bacillus, Acinetobacter, Pseudomonas, and Enterococcus were prevalent after chlorination. Over 75% of the CRB e.g. Acinetobacter, Pseudomonas, Bacillus, and Enterococcus were shared between the chlorination and chloramination, involving potentially pathogens, such as Acinetobacter baumannii and Pseudomonas aeruginosa. Notably, certain genera such as Faecalibacterium, Geobacter, and Megasphaera were enriched as strong CRB after chloramination, whereas Vogesella, Flavobacterium, Thalassolituus, Pseudoalteromonas, and others were enriched after chlorination according to LEfSe analysis. The shared CRB correlated with temperature, pH, and turbidity, displaying a seasonal pattern with varying sensitivity to chlorination and chloramination in cold and warm seasons. These findings enhance our knowledge of the drinking water microbiome and microbial health risks, thus enabling better infectious disease control through enhanced disinfection strategies in DWTPs.
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Affiliation(s)
- Yijun Wei
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Haiyan Wu
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Xudong Zhang
- Water Quality Monitoring Center of Tianjin Water Group Co. Ltd, Tianjin 300240, China
| | - Yongbing Liang
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Danyang Shi
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Lin Wang
- Water Quality Monitoring Center of Tianjin Water Group Co. Ltd, Tianjin 300240, China
| | - Haibei Li
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Hongling Yu
- Water Quality Monitoring Center of Tianjin Water Group Co. Ltd, Tianjin 300240, China
| | - Dong Yang
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Shuqing Zhou
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Tianjiao Chen
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Zhongwei Yang
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Junwen Li
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China
| | - Min Jin
- Department of Environment and Health, Tianjin Institute of Environmental & Operational Medicine, Key Laboratory of Risk Assessment and Control for Environment & Food Safety, Tianjin 300050, China.
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7
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Lim JH, Kang JW. Assessing biofilm formation and resistance of vibrio parahaemolyticus on UV-aged microplastics in aquatic environments. WATER RESEARCH 2024; 254:121379. [PMID: 38422694 DOI: 10.1016/j.watres.2024.121379] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/19/2024] [Revised: 02/21/2024] [Accepted: 02/24/2024] [Indexed: 03/02/2024]
Abstract
UV degradation of marine microplastics (MPs) could increase their vector potential for pathogenic bacteria and threaten human health. However, little is known about how the degree of UV aging affects interactions between MPs and pathogens and how various types of MPs differ in their impact on seafood safety. This study investigated five types of UV-aged MPs and their impact on Vibrio parahaemolyticus, a seafood pathogen. MPs exposed to UV for 60 days showed similar physicochemical changes such as surface cracking and hydrophobicity reduction. Regardless of the type, longer UV exposure of MPs resulted in more biofilm formation on the surface under the same conditions. V. parahaemolyticus types that formed biofilms on the MP surface showed 1.4- to 5.0-fold upregulation of virulence-related genes compared to those that did not form biofilms, independently of UV exposure. However, longer UV exposure increased resistance of V. parahaemolyticus on MPs to chlorine, heat, and human gastrointestinal environment. This study implies that the more UV degradation occurs on MPs, the more microbial biofilm formation is induced, which can significantly increase virulence and environmental resistance of bacteria regardless of the type of MP.
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Affiliation(s)
- Ji-Hwan Lim
- Department of Food Science and Biotechnology, Dongguk University-Seoul, 32, Dongguk-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 10326, Republic of Korea
| | - Jun-Won Kang
- Department of Food Science and Biotechnology, Dongguk University-Seoul, 32, Dongguk-ro, Ilsandong-gu, Goyang-si, Gyeonggi-do 10326, Republic of Korea.
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Deng R, He Q, Yang D, Chen M, Chen Y. Dielectric barrier discharge plasma promotes disinfection-residual-bacteria inactivation via electric field and reactive species. WATER RESEARCH 2024; 254:121386. [PMID: 38457942 DOI: 10.1016/j.watres.2024.121386] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 02/02/2024] [Accepted: 02/25/2024] [Indexed: 03/10/2024]
Abstract
Traditional disinfection processes face significant challenges such as health and ecological risks associated with disinfection-residual-bacteria due to their single mechanism of action. Development of new disinfection processes with composite mechanisms is therefore urgently needed. In this study, we employed liquid ground-electrode dielectric barrier discharge (lgDBD) to achieve synergistic sterilization through electric field electroporation and reactive species oxidation. At a voltage of 12 kV, Pseudomonas fluorescens (ultraviolet and ozone-resistant) and Bacillus subtilis (chlorine-resistant) were completely inactivated within 8 and 6 min, respectively, surpassing a 7.0-log reduction. The lgDBD process showed good disinfection performance across a wide range of pH values and different practical water samples. Staining experiments suggest that cellular membrane damage contributes to this inactivation. In addition, we used a two-dimensional parallel streamer solver with kinetics code to fashion a representative model of the basic discharge unit, and discovered the presence of a persistent electric field during the discharge process with a peak value of 2.86 × 106 V/m. Plasma discharge generates excited state species such as O(1D) and N2(C3Πu), and further forms reactive oxygen and nitrogen species at the gas-liquid interface. The physical process, which is driven by electric field-induced cell membrane electroporation, synergizes with the bactericidal effects of reactive oxygen and nitrogen species to provide effective disinfection. Adopting the lgDBD process enhances sterilization efficiency and adaptability, underscoring its potential to revolutionize physicochemical synergistic disinfection practices.
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Affiliation(s)
- Ruoyu Deng
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Qiang He
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Dongxu Yang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Mengli Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Yi Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
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9
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Xiao X, He M, Ma L, Lv W, Huang K, Yang H, Li Y, Zou L, Xiao Y, Wang W. Insights into microbial contamination and antibiotic resistome traits in pork wholesale market: An evaluation of the disinfection effect of sodium hypochlorite. JOURNAL OF HAZARDOUS MATERIALS 2024; 468:133811. [PMID: 38382341 DOI: 10.1016/j.jhazmat.2024.133811] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 02/06/2024] [Accepted: 02/14/2024] [Indexed: 02/23/2024]
Abstract
Chlorine and its derivatives, such as sodium hypochlorite (NaClO) and chlorine dioxide, are frequently employed as disinfectants throughout the pork supply chain in China. Nevertheless, the extensive use of NaClO has the potential to cause the creation of 'chlorine-tolerant bacteria' and accelerate the evolution of antibiotic resistance. This study evaluated the efficacy of NaClO disinfection by examining alterations in the microbiome and resistome of a pork wholesale market (PWM), and bacteria isolation and analysis were performed to validate the findings. As expected, the taxonomic compositions of bacteria was significantly different before and after disinfection. Notably, Salmonella enterica (S. enterica), Salmonella bongori (S. bongori), Escherichia coli (E. coli), Klebsiella pneumoniae (K. pneumoniae), and Pseudomonas aeruginosa (P. aeruginosa) were observed on all surfaces, indicating that the application of NaClO disinfection treatment in PWM environments for pathogenic bacteria is limited. Correlations were identified between antibiotic resistance genes (ARGs) associated with aminoglycosides (aph(3'')-I, aph(6')-I), quinolone (qnrB, abaQ), polymyxin (arnA, mcr-4) and disinfectant resistance genes (emrA/BD, mdtA/B/C/E/F). Furthermore, correlations were found between risk Rank I ARGs associated with aminoglycoside (aph(3')-I), tetracycline (tetH), beta_lactam (TEM-171), and disinfectant resistance genes (mdtB/C/E/F, emrA, acrB, qacG). Importantly, we found that Acinetobacter and Salmonella were the main hosts of disinfectant resistance genes. The resistance mechanisms of the ARGs identified in PWM were dominated by antibiotic deactivation (38.7%), antibiotic efflux (27.2%), and antibiotic target protection (14.4%). The proportion of genes encoding efflux pumps in the PWM resistome increased after disinfection. Microbial cultures demonstrated that the traits of microbial contamination and antibiotic resistane were consistent with those observed by metagenomic sequencing. This study highlights the possibility of cross-resistance between NaClO disinfectants and antibiotics, which should not be ignored.
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Affiliation(s)
- Xingning Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Miao He
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China; College of Food and Pharmaceutical Sciences, Ningbo University, Ningbo, China
| | - Lingyan Ma
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Wentao Lv
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Kang Huang
- Biological Systems Engineering, Washington State University, Pullman, USA
| | - Hua Yang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China
| | - Yanbin Li
- Department of Biological & Agricultural Engineering, University of Arkansas, Fayetteville, AR 72701, USA
| | - Likou Zou
- College of Resources and Environment, Sichuan Agricultural University, Chengdu, China.
| | - Yingping Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Wen Wang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, MOA Laboratory of Quality & Safety Risk Assessment for Agro-products (Hangzhou), Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
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10
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Kalu CM, Mudau KL, Masindi V, Ijoma GN, Tekere M. Occurrences and implications of pathogenic and antibiotic-resistant bacteria in different stages of drinking water treatment plants and distribution systems. Heliyon 2024; 10:e26380. [PMID: 38434035 PMCID: PMC10906316 DOI: 10.1016/j.heliyon.2024.e26380] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2023] [Revised: 12/05/2023] [Accepted: 02/12/2024] [Indexed: 03/05/2024] Open
Abstract
Different stages of drinking water treatment plants (DWTPs) play specific roles in diverse contaminants' removal present in natural water sources. Although the stages are recorded to promote adequate treatment of water, the occurrence of pathogenic bacteria (PB) and antibiotic-resistant bacteria (ARB) in the treated water and the changes in their diversity and abundance as it passed down to the end users through the drinking water distribution systems (DWDSs), is a great concern, especially to human health. This could imply that the different stages and the distribution system provide a good microenvironment for their growth. Hence, it becomes pertinent to constantly monitor and document the diversity of PB and ARB present at each stage of the treatment and distribution system. This review aimed at documenting the occurrence of PB and ARB at different stages of treatment and distribution systems as well as the implication of their occurrence globally. An exhaustive literature search from Web of Science, Science-Direct database, Google Scholar, Academic Research Databases like the National Center for Biotechnology Information, Scopus, and SpringerLink was done. The obtained information showed that the different treatment stages and distribution systems influence the PB and ARB that proliferate. To minimize the human health risks associated with the occurrence of these PB, the present review, suggests the development of advanced technologies that can promote quick monitoring of PB/ARB at each treatment stage and distribution system as well as reduction of the cost of environomics analysis to promote better microbial analysis.
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Affiliation(s)
- Chimdi M. Kalu
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Khuthadzo L. Mudau
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Vhahangwele Masindi
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
- Magalies Water, Scientific Services, Research & Development Division, Brits, South Africa
| | - Grace N. Ijoma
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
| | - Memory Tekere
- Department of Environmental Science, College of Agriculture and Environmental Sciences, University of South Africa, Florida, 1710, South Africa
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11
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Wang HB, Wu YH, Sun YG, Xu YQ, Chen Z, Xue S, Zhang ZW, Ikuno N, Koji N, Hu HY. Flow-through electrode system (FES): An effective approach for biofouling control of reverse osmosis membranes for municipal wastewater reclamation. WATER RESEARCH 2024; 249:120890. [PMID: 38016222 DOI: 10.1016/j.watres.2023.120890] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2023] [Revised: 10/01/2023] [Accepted: 11/16/2023] [Indexed: 11/30/2023]
Abstract
Emerging electrochemical disinfection techniques provide a promising pathway to the biofouling control of reverse osmosis (RO) process. However, the comparative effectiveness and mechanism of it under flow-through conditions with low voltage remains unclear. This study investigated the effect of a flow-through electrode system (FES) with both direct current (DC) and alternating pulse current (AC) on RO biofouling control compared with chlorine disinfection. At the initial stage of biofouling development, the normalized flux of AC-FES (67% on Day 5) was saliently higher than the control group (56% on Day 5). Subsequently, the normalized fluxes of each group tended similarity in their differences until the 20th day. After mild chemical cleaning, the RO membrane in the AC-FES group reached the highest chemical cleaning efficiency of 58%, implying its foulant was more readily removable and the biofouling was more reversible. The biofouling layer in the DC-FES group was also found to be easily cleanable. Morphological analysis suggested that the thickness and compactness of the fouling layers were the major reasons for the fouling behavior difference. The abundance of 4 fouling-related abundant genera (>1%), which were Pseudomonas, Thiobacillus, Sphingopyxis, and Mycobacterium exhibited a salient correlation with the biofouling degree. The operating cost of FES was also lower than that of chlorine disinfection. In summary, AC-FES is a promising alternative to chlorine disinfection in RO biofouling control, as it caused less and easy-cleaning biofouling layer mainly due to two advantages: a) reducing the regrowth potential after disinfection of the bacteria, leading to alleviated initial fouling, (b) reshaping the microbial community to those with weaker biofilm formation capacity.
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Affiliation(s)
- Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Yi-Ge Sun
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yu-Qing Xu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Song Xue
- CSCEC SCIMEE Sci.& Tech. Co., Ltd, Chengdu 610045, China
| | - Zhuo-Wei Zhang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Nakata Koji
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Shenzhen Environmental Science and New Energy Technology Engineering Laboratory, Tsinghua-Berkeley Shenzhen Institute, Shenzhen 518055, PR China
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12
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Tang MLY, Lau SCK. Effects of chlorination on the survival of sewage bacteria in seawater microcosms. ENVIRONMENTAL MICROBIOLOGY REPORTS 2024; 16:e13216. [PMID: 37990630 PMCID: PMC10866060 DOI: 10.1111/1758-2229.13216] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2023] [Accepted: 11/03/2023] [Indexed: 11/23/2023]
Abstract
Chlorination is a commonly used disinfection method in sewage treatment process. However, resistant bacteria may survive chlorination and enter the receiving aquatic environment upon effluent discharge. There has been limited research on the effects of chlorination on bacterial survival in seawater. To address this knowledge gap, microcosm experiments were conducted to simulate the discharge of chlorinated effluents into coastal seawater. The results revealed that bacterial communities in seawater-based effluents survived better in seawater than those in freshwater-based effluents. High chlorine dosages could significantly reduce the viable bacterial populations and their chance of regrowth in seawater. Additionally, faecal indicator bacteria (FIB) that entered the viable but non-culturable (VBNC) state under chlorination tended to persist in the VBNC state without resuscitation during seawater incubation. Because of the prevalence of VBNC indicator bacteria, qPCR quantification of FIB was more effective than conventional culture-based methods in tracing viable pathogenic chlorine-resistant bacteria, although the correlation strength varied depending on the type of effluent. This study sheds light on how chlorine dosages and the intrinsic properties of effluents affect bacterial survival in seawater and highlights the potential and limitations of using FIB in monitoring the health risks associated with the discharge of chlorinated effluents.
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Affiliation(s)
- Mandy Lok Yi Tang
- Department of Ocean ScienceHong Kong University of Science and TechnologyHong KongChina
| | - Stanley Chun Kwan Lau
- Department of Ocean ScienceHong Kong University of Science and TechnologyHong KongChina
- Center for Ocean Research in Hong Kong and MacauHong Kong University of Science and TechnologyHong KongChina
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13
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Balakrishnan A, Govindaraj S, Dhaipule NGK, Thirumalaisamy N, Anne RS, Sublime N, Philip J. Enhancing microbiologically influenced corrosion protection of carbon steels with silanized epoxy-biocide hybrid coatings. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:13302-13326. [PMID: 38243030 DOI: 10.1007/s11356-024-32014-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/07/2023] [Accepted: 01/10/2024] [Indexed: 01/21/2024]
Abstract
Microbial biofilms and microbiologically influenced corrosion (MIC) pose serious problems in pipelines transporting freshwater from the reservoir to service water systems and fire water systems of power reactors. The present work aims to design a silane-based epoxy-biocide hybrid coating along with antibacterial compounds on carbon steels (CS) for controlling the MIC of pipeline materials. The optimal inhibitory concentrations of biocides are identified and a robust protocol has been developed to prepare epoxy-based coatings impregnated with three biocides (25 ppm each of benzalkonium chloride, bronopol, and isothiazoline). Microbiological and accelerated corrosion studies were carried out by exposing the coated CS specimens to the enriched freshwater bacterial culture (FWC). As compared to the impedance value of 102 Ohms for the polished CS, the values were 106 and 105 Ohms, respectively, for epoxy-coated specimens (CSE) and epoxy-coated specimens impregnated with biocides (CSEB). The corrosion protection efficiency of CSE and CSEB coated specimens exposed to FWC was 99.9% and 98.1%, respectively. Confocal microscopic analysis showed the average biomass thickness was 51.3 ± 0.6 µm and 24.4 ± 0.5 µm, respectively, for CSE and CSEB specimens in comparison to 94.1 ± 0.2 µm on CS specimens. The improved anticorrosion and antifouling behaviors observed in the CSEB specimens suggest that the new coating strategy has the potential for the development of multifunctional hybrid epoxy coatings for pipeline materials to mitigate MIC-related issues in water-transporting pipeline systems.
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Affiliation(s)
- Anandkumar Balakrishnan
- Corrosion Science and Technology Division, MCG, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India.
- Homi Bhabha National Institute Kalpakkam, Mumbai, 400094, India.
| | - Sudharsan Govindaraj
- Department of Biotechnology, Vellore Institute of Technology, Vellore, 632014, India
| | - Nanda Gopala Krishna Dhaipule
- Corrosion Science and Technology Division, MCG, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
| | - Nandakumar Thirumalaisamy
- Corrosion Science and Technology Division, MCG, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
| | - Ravi Shankar Anne
- Corrosion Science and Technology Division, MCG, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
- Homi Bhabha National Institute Kalpakkam, Mumbai, 400094, India
| | - Ningshen Sublime
- Corrosion Science and Technology Division, MCG, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
- Homi Bhabha National Institute Kalpakkam, Mumbai, 400094, India
| | - John Philip
- Homi Bhabha National Institute Kalpakkam, Mumbai, 400094, India
- Materials Characterization Group, Metallurgy and Materials Group, Indira Gandhi Centre for Atomic Research, Kalpakkam, 603102, India
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14
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Espinosa-Barrera PA, Gómez-Gómez M, Vanegas J, Machuca-Martinez F, Torres-Palma RA, Martínez-Pachón D, Moncayo-Lasso A. Systematic analysis of the scientific-technological production on the use of the UV, H 2O 2, and/or Cl 2 systems in the elimination of bacteria and associated antibiotic resistance genes. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:6782-6814. [PMID: 38165540 PMCID: PMC10821820 DOI: 10.1007/s11356-023-31435-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Accepted: 12/05/2023] [Indexed: 01/03/2024]
Abstract
This study presents a systematic review of the scientific and technological production related to the use of systems based on UV, H2O2, and Cl2 for the elimination of antibiotic-resistant bacteria (ARB) and genes associated with antibiotic resistance (ARGs). Using the Pro Know-C (Knowledge Development Process-Constructivist) methodology, a portfolio was created and analyzed that includes 19 articles and 18 patents published between 2011 and 2022. The results show a greater scientific-technological production in UV irradiation systems (8 articles and 5 patents) and the binary combination UV/H2O2 (9 articles and 4 patents). It was emphasized that UV irradiation alone focuses mainly on the removal of ARB, while the addition of H2O2 or Cl2, either individually or in binary combinations with UV, enhances the removal of ARB and ARG. The need for further research on the UV/H2O2/Cl2 system is emphasized, as gaps in the scientific-technological production of this system (0 articles and 2 patents), especially in its electrochemically assisted implementation, have been identified. Despite the gaps identified, there are promising prospects for the use of combined electrochemically assisted UV/H2O2/Cl2 disinfection systems. This is demonstrated by the effective removal of a wide range of contaminants, including ARB, fungi, and viruses, as well as microorganisms resistant to conventional disinfectants, while reducing the formation of toxic by-products.
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Affiliation(s)
- Paula Andrea Espinosa-Barrera
- Grupo de Investigación en Ciencias Biológicas y Químicas, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá D.C., Colombia
- Doctorado en Ciencia Aplicada (DCA), Universidad Antonio Nariño, Bogotá D.C., Colombia
| | - Marcela Gómez-Gómez
- Grupo de Investigación en Ciencias Biológicas y Químicas, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá D.C., Colombia
| | - Javier Vanegas
- Grupo de Investigación en Ciencias Biológicas y Químicas, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá D.C., Colombia
| | - Fiderman Machuca-Martinez
- Centro de Excelencia en Nuevos Materiales, Universidad del Valle, Calle 13 No. 100-00, Cali, Colombia
| | - Ricardo Antonio Torres-Palma
- Grupo de Investigación en Remediación Ambiental y Biocatálisis (GIRAB), Instituto de Química, Facultad de Ciencias Exactas y Naturales, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín, Colombia
| | - Diana Martínez-Pachón
- Grupo de Investigación en Ciencias Biológicas y Químicas, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá D.C., Colombia
| | - Alejandro Moncayo-Lasso
- Grupo de Investigación en Ciencias Biológicas y Químicas, Facultad de Ciencias, Universidad Antonio Nariño, Bogotá D.C., Colombia.
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15
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Ren X, Zhang S, Wu M, Xiao B, Miao H, Chen H. Effect and influence mechanism of biofilm formation on the biological stability of reclaimed water. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167735. [PMID: 37827320 DOI: 10.1016/j.scitotenv.2023.167735] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2023] [Revised: 10/08/2023] [Accepted: 10/08/2023] [Indexed: 10/14/2023]
Abstract
Microorganisms and sediments in reclaimed water adhere to the inner walls of pipes or water tanks, forming biofilms that support the continuous growth of microorganisms. These biofilms provide a protective barrier, shielding bacteria from disinfectants. This study investigated the impact of biofilms on bacterial growth and reproduction in reclaimed water and the factors limiting bacterial growth in reclaimed graywater (GMR) and reclaimed mixed wastewater (MWR). The results revealed that biofilm biomass gradually increased and reached a maximum value on Days 20-25, and the biomass of organisms continued to decrease after 40 days. Biofilms serve as a source of bacteria, continuously releasing them into reclaimed water systems. The presence of biofilms reduced the biological stability of the reclaimed water, leading to water quality deterioration. The concentration of assimilable organic carbon in the reclaimed water showed a positive correlation with the heterotrophic bacterial count and Escherichia coli levels in both the reclaimed water and biofilms. The threshold value of chlorine for inhibiting biofilms in reclaimed water was no <2 mg/L. High concentrations of free chlorine delayed the growth of biofilms but did not reduce the final biomass generated by the biofilms. Carbon was the limiting factor for the biological stability of reclaimed water, while nitrogen, phosphorus, and inorganic salts were not limiting factors. Thus, minimizing the concentration of organic matter in reclaimed water can reduce the nutrient sources available for biofilm formation. This study provides support for advancements in the wastewater reuse industry.
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Affiliation(s)
- Xueli Ren
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China.
| | - Shudong Zhang
- School of Ecological and Environmental Sciences, East China Normal University, Shanghai 200241, China
| | - Mengyi Wu
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Beiqi Xiao
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Hengfeng Miao
- School of Environment and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Hongbin Chen
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China.
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16
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Sun YG, Wang HB, Wu YH, Cao KF, Chen Z, Ikuno N, Koji N, Hu HY. High-efficiency and low-carbon inactivation of UV resistant bacteria in reclaimed water by flow-through electrode system (FES). THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166297. [PMID: 37595918 DOI: 10.1016/j.scitotenv.2023.166297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/20/2023]
Abstract
With the increasingly serious shortage of water resources globally, it has been paid more attention on how to secure the biosafety of reclaimed water and other non-traditional water sources. However, the 3 most applied disinfection technics, which are chlorine, ultraviolet (UV), and ozone disinfection, all have their disadvantages of selecting undesired bacteria and low energy utilization efficiency. Electrode disinfection is a promising solution, but the current electrode disinfection process still needs to be optimized in terms of the use conditions of the configuration reactivation. In this paper, we built a flow electrode system (FES). To evaluate the disinfection techniques more precisely, we isolated ultraviolet-resistant bacteria (URB) bacteria from the water of the full-scale water plant and tested the disinfection performance of FES and UV. The inactivation rate, reactivation potential, and energy consumption were analyzed. FES could inactivate 99.99 % of the URB and cause irreversible damage to the residual bacteria. FES could make all bacteria strains apoptosis in the subsequent 24 h of storage after alternating pulse current (APC) treatment, 3 V, within 27.7 s. Besides, the energy consumption of FES is about 2 orders lower than that of UV disinfection under the same inactivation rate. In summary, APC-FES is an efficient and low-carbon alternative for future water disinfection, which could achieve the ideal disinfection effect of a high inactivation rate, no reactivation, and low energy consumption.
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Affiliation(s)
- Yi-Ge Sun
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Nakata Koji
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, PR China
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17
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Mao Y, Chen Z, Lu Y, Cao KF, Wu Y, Hu HY. Inactivation of Bacteria in Water by Ferrate(VI): Efficiency and Mechanisms. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023; 57:20893-20904. [PMID: 38032700 DOI: 10.1021/acs.est.3c05118] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/01/2023]
Abstract
Ferrate (Fe(VI)) is an emerging green disinfectant and has received increasing attention nowadays. This study conducted systematic analyses of Fe(VI) disinfection on six typical bacteria in different water matrices. The results showed that Fe(VI) was more effective in inactivating Gram-negative (G-) bacteria than Gram-positive (G+) bacteria, and the disinfection performance of Fe(VI) was better in a phosphate buffer than that in a borate buffer and secondary effluent. The inactivation rate constants of G- bacteria were significantly higher than those of G+ bacteria. The cell membrane damage of G- bacteria was also more severe than that of G+ bacteria after Fe(VI) treatment. The cell wall structure, especially cell wall thickness, might account for the difference of the inactivation efficiency between G- bacteria and G+ bacteria. Moreover, it is revealed that Fe(VI) primarily reacted with proteins rather than other biological molecules (i.e., phospholipids, peptidoglycan, and lipopolysaccharide). This was further evidenced by the reduction of bacterial autofluorescence due to the destruction of bacterial proteins during Fe(VI) inactivation. Overall, this study advances the understanding of Fe(VI) disinfection mechanisms and provides valuable information for the Fe(VI) application in water disinfection.
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Affiliation(s)
- Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Yinhu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, P. R. China
- Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou 215163, P. R. China
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18
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Mehdipour M, Gholipour S, Mohammadi F, Hatamzadeh M, Nikaeen M. Incidence of co-resistance to antibiotics and chlorine in bacterial biofilm of hospital water systems: Insights into the risk of nosocomial infections. J Infect Public Health 2023; 16 Suppl 1:210-216. [PMID: 37951730 DOI: 10.1016/j.jiph.2023.10.032] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/23/2023] [Accepted: 10/26/2023] [Indexed: 11/14/2023] Open
Abstract
The presence of biofilms in drinking water distribution systems (DWDS) in healthcare settings poses a considerable risk to the biological security of water, particularly when the biofilm bacteria demonstrate antimicrobial resistance characteristics. This study aimed to investigate the occurrence of antibiotic-resistant bacteria (ARB) in biofilms within DWDS of hospitals. The chlorine resistance of the isolated ARB was analyzed, and then chlorine-resistant bacteria (CRB) were identified using molecular methods. Additionally, the presence of several antibiotic resistance genes (ARGs) was monitored in the isolated ARB. Out of the 41 biofilm samples collected from hospitals, ARB were detected in 32 (78%) of the samples. A total of 109 colonies of ARB were isolated from DWDS of hospitals, with β-lactam resistant bacteria, including ceftazidime-resistant and ampicillin-resistant bacteria, being the most frequently isolated ARB. Analyzing of ARGs revealed the highest detection of aac6, followed by sul1 gene. However, the β-lactamase genes blaCTX-M and blaTEM were not identified in the ARB, suggesting the presence of other β-lactamase genes not included in the tested panel. Exposure of ARB to free chlorine at a concentration of 0.5 mg/l showed that 64% of the isolates were CRB. However, increasing the chlorine concentration to 4 mg/l decreased the high fraction of ARB (91%). The dominant CRB identified were Sphingomonas, Brevundimonas, Stenotrophomonas, Bacillus and Staphylococcus with Bacillus exhibiting the highest frequency. The results highlight the potential risk of biofilm formation in the DWDS of hospitals, leading to the dissemination of ARB in hospital environments, which is a great concern for the health of hospitalized patients, especially vulnerable individuals. Surveillance of antimicrobial resistance in DWDS of hospitals can provide valuable insights for shaping antimicrobial use policies and practices that ensure their efficacy.
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Affiliation(s)
- Mohammadmehdi Mehdipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Student Research Committee, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Sahar Gholipour
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Farzaneh Mohammadi
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Maryam Hatamzadeh
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran
| | - Mahnaz Nikaeen
- Department of Environmental Health Engineering, School of Health, Isfahan University of Medical Sciences, Isfahan, Iran; Environment Research Center, Research Institute for Primordial Prevention of Non-Communicable Diseases, Isfahan University of Medical Sciences, Isfahan, Iran.
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19
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Xu G, Yang P, Zhang Y, Sun L, Hu X, Zhang W, Tu Y, Tian Y, Li A, Xie X, Gu X. Porous pillararene-based polymer as adsorbent and solid disinfectant for water treatment. CHEMOSPHERE 2023; 341:140056. [PMID: 37696480 DOI: 10.1016/j.chemosphere.2023.140056] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/15/2023] [Revised: 08/27/2023] [Accepted: 09/02/2023] [Indexed: 09/13/2023]
Abstract
Pillararene polymers have been widely used as excellent adsorbents for water treatment, but pillararene polymers with ultra-high specific surface area and versatility are still rarely reported. Herein, a quaternary ammonium salt modified pillar [5] arene polymer, QPBP [5], with specific surface area of 1844 m2 g-1 was successfully synthesized. Since QPBP [5] has abundant different adsorption sites, it exhibits excellent performance for the simultaneously removal of organic pollutants with different charges from water. The selected three model pollutants, Rhodamine B (RhB, positively charged), Sulfamethazine (SMT, electrically neutral) and Fulvic acid (FA, negatively charged), could be rapidly and efficiently removed from water by QPBP [5] within 10 min, which are much faster than them by most of the reported adsorbents. RhB and SMT are mainly adsorbed through hydrophobic interactions with the QPBP [5] surface, while FA is mainly removed through ion exchange. In addition, QPBP [5] also showed excellent reusability and adsorption performance for the environmentally relevant concentration of pollutants. Furthermore, the quaternary ammonium groups on QPBP [5] makes it a solid disinfectant with excellent antibacterial properties. In conclusion, QPBP [5] is a promising multifunctional adsorbent for the treatment of complex pollutants in water.
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Affiliation(s)
- Guizhou Xu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Pingping Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Yalan Zhang
- Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Resources and Environment, Nanchang University, Nanchang 330031, PR China
| | - Lin Sun
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Xuejiao Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Wenrui Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Yizhou Tu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Yuansong Tian
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China
| | - Aimin Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China; Nanjing University & Yancheng Academy of Environment Protection Technology and Engineering, Nanjing, 210023, PR China
| | - Xianchuan Xie
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China; Key Laboratory of Poyang Lake Environment and Resource Utilization, Ministry of Education, School of Resources and Environment, Nanchang University, Nanchang 330031, PR China; Jiangxi Nanxin Environmental Protection Technology Co. LTD, Jiujiang City of Jiangxi Province, 330300, PR China; Nanjing University & Yancheng Academy of Environment Protection Technology and Engineering, Nanjing, 210023, PR China.
| | - Xueyuan Gu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing 210023, PR China.
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20
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Baig MIR, Kadu P, Bawane P, Nakhate KT, Yele S, Ojha S, Goyal SN. Mechanisms of emerging resistance associated with non-antibiotic antimicrobial agents: a state-of-the-art review. J Antibiot (Tokyo) 2023; 76:629-641. [PMID: 37605076 DOI: 10.1038/s41429-023-00649-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Revised: 06/27/2023] [Accepted: 07/20/2023] [Indexed: 08/23/2023]
Abstract
Although the development of resistance by microorganisms to antimicrobial drugs has been recognized as a global public health concern, the contribution of various non-antibiotic antimicrobial agents to the development of antimicrobial resistance (AMR) remains largely neglected. The present review discusses various chemical substances and factors other than typical antibiotics, such as preservatives, disinfectants, biocides, heavy metals and improper chemical sterilization that contribute to the development of AMR. Furthermore, it encompasses the mechanisms like co-resistance and co-selection, horizontal gene transfer, changes in the composition and permeability of cell membrane, efflux pumps, transposons, biofilm formation and enzymatic degradation of antimicrobial chemicals which underlie the development of resistance to various non-antibiotic antimicrobial agents. In addition, the review addresses the resistance-associated changes that develops in microorganisms due to these agents, which ultimately contribute to the development of resistance to antibiotics. In order to prevent the indiscriminate use of chemical substances and create novel therapeutic agents to halt resistance development, a more holistic scientific approach might provide diversified views on crucial factors contributing to the persistence and spread of AMR. The review illustrates the common and less explored mechanisms contributing directly or indirectly to the development of AMR by non-antimicrobial agents that are commonly used.
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Affiliation(s)
- Mirza Ilyas Rahim Baig
- Department of Pharmaceutics, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, Maharashtra, 400056, India
| | - Pramod Kadu
- Department of Pharmaceutics, SVKM's Dr. Bhanuben Nanavati College of Pharmacy, Mumbai, Maharashtra, 400056, India.
| | - Pradip Bawane
- Department of Pharmacognosy, Shri Vile Parle Kelavani Mandal's Institute of Pharmacy, Dhule, Maharashtra, 424001, India
| | - Kartik T Nakhate
- Department of Pharmacology, Shri Vile Parle Kelavani Mandal's Institute of Pharmacy, Dhule, Maharashtra, 424001, India
| | - Santosh Yele
- Department of Pharmacognosy, SVKM's NMIMS, School of Pharmacy & Technology Management, Hyderabad, 509301, India
| | - Shreesh Ojha
- Department of Pharmacology and Therapeutics, College of Medicine and Health Sciences, United Arab Emirates University, P.O. Box 15551, Al Ain, United Arab Emirates
| | - Sameer N Goyal
- Department of Pharmacology, Shri Vile Parle Kelavani Mandal's Institute of Pharmacy, Dhule, Maharashtra, 424001, India
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21
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Shi Q, Chen Z, Yan H, Xu M, Cao KF, Mao Y, Chen X, Hu HY. Identification of significant live bacterial community shifts in different reclaimed waters during ozone and chlorine disinfection. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165199. [PMID: 37391159 DOI: 10.1016/j.scitotenv.2023.165199] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/11/2023] [Revised: 06/12/2023] [Accepted: 06/27/2023] [Indexed: 07/02/2023]
Abstract
Ozone and chlorine are the most widely used disinfectants for water and wastewater disinfection. They play important role in microbial inactivation but could also pose a considerable selection effect on the microbial community of reclaimed water. Classical culture-based methods that rely on the assessment of conventional bacterial indicators (e.g., coliform bacteria) could hardly reflect the survival of disinfection residual bacteria (DRB) and hidden microbial risks in disinfected effluents. Hence, this study investigated the shifts of live bacterial community during ozone and chlorine disinfection in three reclaimed waters (i.e., two secondary effluents and one tertiary effluent), adopting Illumina Miseq sequencing technology in combination with a viability assay, propidium monoazide (PMA) pretreatment. Notably, statistical analyses of Wilcoxon rank-sum test confirmed the existance of distinct differences in bacterial community structure between samples with or without PMA pretreatment. On the phylum level, Proteobacteria commonly dominated in three undisinfected reclaimed waters, while ozone and chlorine disinfection posed varied effects on its relative abundance among different influents. On the genus level, ozone and chlorine disinfection significantly changed the bacterial composition and dominant species in reclaimed waters. Specifically, the typical DRB identified in ozone disinfected effluents were Pseudomonas, Nitrospira and Dechloromonas, while for chlorine disinfected effluents, Pseudomonas, Legionella, Clostridium, Mycobacterium and Romboutsia were recognized as typical DRB, which call for much attention. The Alpha and Beta diversity analysis results also suggested that different influent compositions greatly affected the bacterial community structure during disinfection processes. Since the experiments in present study were conducted in a short period and the dataset was relatively limited, prolonged experiment under different operational conditions are needed in future to illustrate the potential long-term effects of disinfection on the microbial community structure. The findings of this study could provide insights into microbial safety concern and control after disinfection for sustainable water reclamation and reuse.
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Affiliation(s)
- Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Han Yan
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Meiying Xu
- State Key Laboratory of Applied Microbiology Southern China, Institute of Microbiology, Guangdong Academy of Sciences, Guangzhou 510070, PR China
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China
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Wang M, Wang H, Hu C, Deng J, Shi B. Phthalate acid esters promoted the enrichment of chlorine dioxide-resistant bacteria and their functions related to human diseases in rural polyvinyl chloride distribution pipes. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 896:165282. [PMID: 37406691 DOI: 10.1016/j.scitotenv.2023.165282] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/09/2023] [Revised: 06/09/2023] [Accepted: 07/01/2023] [Indexed: 07/07/2023]
Abstract
Polyvinyl chloride (PVC) pipes are widely used as drinking water distribution pipes in rural areas of China. However, whether phthalate acid esters (PAEs) released from PVC pipes will affect tap water quality is still unknown. The influence of released PAEs on the water quality was analysed in this study, especially after ClO2 disinfection. The results indicated that ClO2 disinfection could control the growth of total coliforms and heterotrophic bacteria (HPC). However, when the ClO2 residual decreased to below 0.10 mg/L, HPC and opportunistic pathogens, including Mycobacterium avium and Pseudomonas aeruginosa, increased significantly. In addition, after ClO2 disinfection, PAEs concentrations increased from 10.6-22.2 μg/L to 21.2-58.8 μg/L in different sampling cites. Linear discriminant analysis (LDA) effect size (LEfSe) and statistical analysis of metagenomic profiles (Stamp) showed that ClO2 disinfection induced the enrichment of Pseudomonas, Bradyrhizobium, and Mycobacterium and functions related to human diseases, such as pathogenic Escherichia coli infection, shigellosis, Staphylococcus aureus infection, and Vibrio cholerae infection. The released PAEs not only promoted the growth of these ClO2-resistant bacterial genera but also enhanced their functions related to human diseases. Moreover, these PAEs also induced the enrichment of other bacterial genera, such as Blastomonas, Dechloromonas, and Kocuria, and their functions, such as chronic myeloid leukaemia, African trypanosomiasis, leishmaniasis, hepatitis C and human T-cell leukaemia virus 1 infection. The released PAEs enhanced the microbial risk of the drinking water. These results are meaningful for guaranteeing water quality in rural areas of China.
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Affiliation(s)
- Min Wang
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China; Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China
| | - Haibo Wang
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China.
| | - Chisheng Hu
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jianmian Deng
- Institute of Environmental and Municipal Engineering, North China University of Water Resources and Electric Power, Zhengzhou 450045, China.
| | - Baoyou Shi
- Key Laboratory of Drinking Water Science and Technology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China
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23
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Hu Z, Bai X. Self-repair and resuscitation of viable injured bacteria in chlorinated drinking water: Achromobacter as an example. WATER RESEARCH 2023; 245:120585. [PMID: 37690414 DOI: 10.1016/j.watres.2023.120585] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2023] [Revised: 08/24/2023] [Accepted: 09/04/2023] [Indexed: 09/12/2023]
Abstract
Chlorine disinfection for the treatment of drinking water can cause injury to the membrane and DNA of bacterial cells and may induce the surviving injured bacteria into a viable but non-culturable (VBNC) state. It is difficult to monitor viable injured bacteria by heterotrophic plate counting (HPC), and their presence is also easily miscalculated in flow cytometry intact cell counting (FCM-ICC). Viable injured bacteria have a potential risk of resuscitation in drinking water distribution systems (DWDSs) and pose a threat to public health when drinking from faucets. In this study, bacteria with injured membranes were isolated from chlorinated drinking water by FCM cell sorting. The culture rate of injured bacteria varied from 0.08% to 2.6% on agar plates and 0.39% to 6.5% in 96-well plates. As the dominant genus among the five identified genera, as well as an opportunistic pathogen with multiple antibiotic resistance, Achromobacter was selected and further studied. After treatment with chlorine at a concentration of 1.2 mg/L, Achromobacter entered into the intermediate injured state on the FCM plot, and the injury on the bacterial surface was observed by electron microscopy. However, the CTC respiratory activity assay showed that 75.0% of the bacteria were still physiologically active, and they entered into a VBNC state. The injured VBNC Achromobacter in sterile drinking water were resuscitated after approximately 25 h. The cellular repair behavior of injured bacteria was studied by Fourier transform infrared attenuated total reflectance (FTIR-ATR) and comet assays. It was found that DNA injury rather than membrane injury was repaired first. The expression of Ku and ligD increased significantly during the DNA repair period, indicating that non-homologous end-joining (NHEJ) played an important role in repairing DNA double-strand breaks. This study deepened the understanding of the effect of chlorine disinfection on bacterial viability in drinking water and will provide support for the improvement of the chlorine disinfection process for the treatment of drinking water.
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Affiliation(s)
- Zengyi Hu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Xiaohui Bai
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China.
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24
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Xu YQ, Wu YH, Luo LW, Huang BH, Chen Z, Wang HB, Liu H, Ikuno N, Koji N, Hu HY. Inactivation of chlorine-resistant bacteria (CRB) via various disinfection methods: Resistance mechanism and relation with carbon source metabolism. WATER RESEARCH 2023; 244:120531. [PMID: 37659185 DOI: 10.1016/j.watres.2023.120531] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/10/2023] [Revised: 08/22/2023] [Accepted: 08/25/2023] [Indexed: 09/04/2023]
Abstract
With the widespread use of chlorine disinfection, chlorine-resistant bacteria (CRB) in water treatment systems have gained public attention. Bacterial chlorine resistance has been found positively correlated with extracellular polymeric substance (EPS) secretion. In this study, we selected the most suitable CRB controlling method against eight bacterial strains with different chlorine resistance among chloramine, ozone, and ultraviolet (UV) disinfection, analyzed the resistance mechanisms, clarified the contribution of EPS to disinfection resistance, and explored the role of carbon source metabolism capacity. Among all the disinfectants, UV disinfection showed the highest disinfection capacity by achieving the highest average and median log inactivation rates for the tested strains. For Bacillus cereus CR19, the strain with the highest chlorine resistance, 40 mJ/cm2 UV showed a 1.90 log inactivation, which was much higher than that of 2 mg-Cl2/L chlorine (0.67 log), 2 mg-Cl2/L chloramine (1.68 log), and 2 mg/L ozone (0.19 log). Meanwhile, the UV resistance of the bacteria did not correlate with EPS secretion. These characteristics render UV irradiation the best CRB controlling disinfection method. Chloramine was found to have a generally high inactivation efficiency for bacteria with high chlorine-resistance, but a low inactivation efficiency for low chlorine-resistant ones. Although EPS consumed up to 56.7% of chloramine which an intact bacterial cell consumed, EPS secretion could not explain chloramine resistance. Thus, chloramine is an acceptable CRB control method. Similar to chlorine, ozone generally selected high EPS-secreting bacteria, with EPS consuming up to 100% ozone. Therefore, ozone is not an appropriate method for controlling CRB with high EPS secretion. EPS played an important role in all types of disinfection resistance, and can be considered the main mechanism for bacterial chlorine and ozone disinfection resistance. However, as EPS was not the main resistance mechanism in UV and chloramine disinfection, CRB with high EPS secretion were inactivated more effectively. Furthermore, carbon source metabolism was found related to the multiple resistance of bacteria. Those with low carbon source metabolism capacity tended to have higher multiple resistance, especially to chlorine, ozone, and UV light. Distinctively, among the tested gram-negative bacteria, in contrast to other disinfectants, chloramine resistance was negatively correlated with EPS secretion and positively correlated with carbon source metabolism capacity, suggesting a special disinfection mechanism.
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Affiliation(s)
- Yu-Qing Xu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Bang-Hao Huang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Han Liu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Nakata Koji
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou, Jiangsu 215163, PR China
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25
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Chen X, Chen Z, Ngo HH, Mao Y, Cao K, Shi Q, Lu Y, Hu HY. Comparison of inactivation characteristics between Gram-positive and Gram-negative bacteria in water by synergistic UV and chlorine disinfection. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 333:122007. [PMID: 37302789 DOI: 10.1016/j.envpol.2023.122007] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2023] [Revised: 04/23/2023] [Accepted: 06/08/2023] [Indexed: 06/13/2023]
Abstract
Disinfection is essential in water and wastewater treatment process as a guarantee for microbial safety. This study systematically investigated: (i) the inactivation characteristics of bacteria widely existed in water, including Gram-negative bacteria (Escherichiacoli) and Gram-positive bacteria (Staphylococcus aureus and Bacillus subtilis spores), by sequential UV and chlorine disinfection processes (UV-Cl and Cl-UV), simultaneous UV and chlorine disinfection process (UV/Cl); and (ii) the disinfection mechanisms on different bacteria. The combination of UV and chlorine disinfection could inactive bacteria at lower doses, but showed no synergistic effect on E. coli. Contrarily, disinfection results indicated that UV/Cl performed an obvious synergistic effect on highly disinfectant-resistant bacteria (e.g. S. aureus and B. subtilis spores). Specifically, UV/Cl at the UV dose of 9 mJ/cm2 and chlorine dose of 2 mg-Cl/L could inactivate S. aureus completely. Moreover, the effectiveness of UV/Cl on the removal of indigenous bacteria in actual water conditions was also confirmed. In short, the study provides significant theoretical and practical implications for ensuring microbial safety during water treatment and use.
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Affiliation(s)
- Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China.
| | - Huu Hao Ngo
- School of Civil and Environmental Engineering, University of Technology Sydney, Broadway, NSW, 2007, Australia
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Kefan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing, 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing, 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou, 215163, PR China
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26
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Liu S, Li Q, Jiang R, Liu P, Zhang XX. Shift of human pathogen community composition and their potential human health risk after supply suspension in tap water. Sci Rep 2023; 13:12419. [PMID: 37528119 PMCID: PMC10393962 DOI: 10.1038/s41598-023-39225-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2023] [Accepted: 07/21/2023] [Indexed: 08/03/2023] Open
Abstract
Water supply suspension-restoration can occur frequently due to the overhauling of civil infrastructure in developing countries and the shutdown of commercial buildings during the pandemic. For comprehensive insights into the effects of water supply suspension-restoration, this study characterized the variations of the pathogen community composition of the tap water and their infection risk under different water supply scenarios. Metagenomic sequencing revealed a significant change of the human pathogen profiles, among which the most dominant pathogen changed from Pseudomonas aeruginosa (4.91%) to Acinetobacter johnsonii (0.59%). Furthermore, absolute quantification of pathogens by propidium-monoazide-qPCR revealed that the abundance of the three typical pathogens (Pseudomonas aeruginosa, Mycobacterium avium and Salmonella sp.) showed an increase of 2.44 log to 3.60 log immediately after water supply suspension-restoration and did not return to the normal level even after 2-h supply restoration, except for Pseudomonas aeruginosa. Quantitative microbial risk assessment suggested the infection risks of the three pathogens arising from direct utilization of tap water under stable water supply, including dermal exposure and oral intake, were all above the threshold of 10-4, and evidently increased after water supply suspension-restoration. This study warns us against the risk induced by the pathogens in tap water, especially after water supply suspension-restoration.
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Affiliation(s)
- Shengnan Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Road, Nanjing, 210023, China
| | - Qisheng Li
- China Three Gorges Construction Engineering Corporation, Beijing, 100048, China
| | - Ruiming Jiang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Road, Nanjing, 210023, China
| | - Peng Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Road, Nanjing, 210023, China.
| | - Xu-Xiang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, 163 Xianlin Road, Nanjing, 210023, China.
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27
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Oliveira IM, Gomes IB, Plácido A, Simões LC, Eaton P, Simões M. The impact of potassium peroxymonosulphate and chlorinated cyanurates on biofilms of Stenotrophomonas maltophilia: effects on biofilm control, regrowth, and mechanical properties. BIOFOULING 2023; 39:691-705. [PMID: 37811587 DOI: 10.1080/08927014.2023.2254704] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2023] [Accepted: 08/27/2023] [Indexed: 10/10/2023]
Abstract
The activity of two chlorinated isocyanurates (NaDCC and TCCA) and peroxymonosulphate (OXONE) was evaluated against biofilms of Stenotrophomonas maltophilia, an emerging pathogen isolated from drinking water (DW), and for the prevention of biofilm regrowth. After disinfection of pre-formed 48 h-old biofilms, the culturability was reduced up to 7 log, with OXONE, TCCA, and NaDCC showing more efficiency than free chlorine against biofilms formed on stainless steel. The regrowth of biofilms previously exposed to OXONE was reduced by 5 and 4 log CFU cm-2 in comparison to the unexposed biofilms and biofilms exposed to free chlorine, respectively. Rheometry analysis showed that biofilms presented properties of viscoelastic solid materials, regardless of the treatment. OXONE reduced the cohesiveness of the biofilm, given the significant decrease in the complex shear modulus (G*). AFM analysis revealed that biofilms had a fractured appearance and smaller bacterial aggregates dispersed throughout the surface after OXONE exposure than the control sample. In general, OXONE has been demonstrated to be a promising disinfectant to control DW biofilms, with a higher activity than chlorine. The results also show the impact of the biofilm mechanical properties on the efficacy of the disinfectants in biofilm control.
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Affiliation(s)
- I M Oliveira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - I B Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
| | - A Plácido
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
| | - L C Simões
- CEB - Centre of Biological Engineering, University of Minho, Braga, Portugal
- LABBELS - Associate Laboratory in Biotechnology, Bioengineering and Microelectromechanical Systems, Braga/Guimarães, Portugal
| | - P Eaton
- REQUIMTE/LAQV - Associated Laboratory for Green Chemistry of the Network of Chemistry and Technology, Department of Chemistry and Biochemistry, Faculty of Sciences, University of Porto, Porto, Portugal
- The Bridge, School of Chemistry, University of Lincoln, Lincoln, UK
| | - M Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Porto, Portugal
- ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Porto, Portugal
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Pan R, Zhang TY, Zheng ZX, Ai J, Ye T, Zhao HX, Hu CY, Tang YL, Fan JJ, Geng B, Xu B. Insight into mixed chlorine/chloramines conversion and associated water quality variability in drinking water distribution systems. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 880:163297. [PMID: 37028653 DOI: 10.1016/j.scitotenv.2023.163297] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/06/2023] [Revised: 03/29/2023] [Accepted: 04/01/2023] [Indexed: 05/27/2023]
Abstract
Mixed chlorine/chloramines are common in drinking water distribution systems (DWDSs); however, their transformation and impact on chemical and microbial characteristics are not well understood. We systematically investigated water quality parameters associated with mixed chlorine/chloramine species conversion in 192 samples (including raw, finished, and tap water) collected throughout the year in a city in East China. Various chlorine/chloramine species (free chlorine, monochloramine [NH2Cl], dichloramine [NHCl2], and organic chloramines [OC]) were detected in both chlorinated and chloraminated DWDSs. NHCl2 + OC increased with transport distance along the pipeline network. The maximum proportion of NHCl2 + OC in over total chlorine in tap water reached 66 % and 38 % from chlorinated and chloraminated DWDSs, respectively. Both free chlorine and NH2Cl showed a rapid decay in the water pipe systems, but NHCl2 and OC were more persistent. Correlations between chlorine/chloramine species and physicochemical parameters were established. Models for predicting the sum of chloroform/TCM, bromodichloromethane/BDCM, chlorodibromomethane/CBDM, and bromoform/TBM (THM4) (R2 = 0.56) and haloacetic acids (HAAs) (R2 = 0.65) exhibited greater accuracy based on machine learning tuned with chlorine/chloramine species, particularly NHCl2 + OC. The predominant bacterial communities in mixed chlorine/chloramine systems were those resistant to chlorine or chloramine such as proteobacteria. NH2Cl was the most significant explanatory factor (28.1 %) for the variation in microbial community assemblage in chloraminated DWDSs. Although residual free chlorine and NHCl2 + OC, accounted for a smaller proportion of chlorine species in chloraminated DWDSs, they played an essential role (12.4 % and 9.1 %, respectively) in the microbial community structure.
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Affiliation(s)
- Renjie Pan
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Zheng-Xiong Zheng
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Jian Ai
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Tao Ye
- Department of Civil and Environmental Engineering, South Dakota School of Mines and Technology, Rapid City, SD 57701, USA
| | - Heng-Xuan Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Chen-Yan Hu
- College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, PR China
| | - Yu-Lin Tang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Jing-Jing Fan
- Shanghai Chengtou Water (Group) Co. LTD, Shanghai 200002, PR China
| | - Bing Geng
- Shanghai Chengtou Water (Group) Co. LTD, Shanghai 200002, PR China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Urban Water Supply, Water Saving and Water Environment Governance in the Yangtze River Delta of Ministry of Water Resources, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Wang M, Zhang Y, Niu Z, Miao Q, Fu W. Study on the distribution characteristics and metabolic mechanism of chlorine-resistant bacteria in indoor water supply networks. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 328:121640. [PMID: 37059174 DOI: 10.1016/j.envpol.2023.121640] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/07/2023] [Revised: 03/31/2023] [Accepted: 04/12/2023] [Indexed: 05/09/2023]
Abstract
The presence and attachment of chlorine-resistant bacteria on the surface of water distribution network will deteriorate water quality and threaten human health. Chlorination is critical in drinking water treatment to ensure the biosafety of drinking water. However, how disinfectants affect the structures of dominant flora during biofilm development and whether the changes are consistent with the free flora remain unclear. Therefore, we investigated changes in species diversity and relative abundance of different bacterial communities in planktonic and biofilm samples at different chlorine residual concentrations (blank, 0.3 mg/L, 0.8 mg/L, 2.0 mg/L and 4.0 mg/L), and the main reasons for the development of chlorine resistance in bacteria was also discussed. The results showed that the richness of microbial species in the biofilm was higher than that in planktonic microbial samples. In the planktonic samples, Proteobacteria and Actinobacteria were the dominant groups regardless of the chlorine residual concentration. For biofilm samples, the dominant position of Proteobacteria bacteria was gradually replaced by actinobacteria bacteria with the increase of chlorine residual concentration. In addition, at higher chlorine residual concentration, Gram-positive bacteria were more concentrated to form biofilms. There are three main reasons for the generation of chlorine resistance of bacteria: enhanced function of efflux system, activated bacterial self-repair system, and enhanced nutrient uptake capacity.
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Affiliation(s)
- Mengyuan Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China; College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Ying Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China.
| | - Zhiguang Niu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300350, China; The International Joint Institute of Tianjin University, Fuzhou, 350207, China
| | - Qinkui Miao
- College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Wei Fu
- College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
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30
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Pereira AR, Braga DFO, Vassal M, Gomes IB, Simões M. Ultraviolet C irradiation: A promising approach for the disinfection of public spaces? THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 879:163007. [PMID: 36965719 DOI: 10.1016/j.scitotenv.2023.163007] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2022] [Revised: 03/10/2023] [Accepted: 03/18/2023] [Indexed: 05/17/2023]
Abstract
Ultraviolet irradiation C (UVC) has emerged as an effective strategy for microbial control in indoor public spaces. UVC is commonly applied for air, surface, and water disinfection. Unlike common 254 nm UVC, far-UVC at 222 nm is considered non-harmful to human health, being safe for occupied spaces, and still effective for disinfection purposes. Therefore, and allied to the urgency to mitigate the current pandemic of SARS-CoV-2, an increase in UVC-based technology devices appeared in the market with levels of pathogens reduction higher than 99.9 %. This environmentally friendly technology has the potential to overcome many of the limitations of traditional chemical-based disinfection approaches. The novel UVC-based devices were thought to be used in public indoor spaces such as hospitals, schools, and public transport to minimize the risk of pathogens contamination and propagation, saving costs by reducing manual cleaning and equipment maintenance provided by manpower. However, a lack of information about UVC-based parameters and protocols for disinfection, and controversies regarding health and environmental risks still exist. In this review, fundamentals on UVC disinfection are presented. Furthermore, a deep analysis of UVC-based technologies available in the market for the disinfection of public spaces is addressed, as well as their advantages and limitations. This comprehensive analysis provides valuable inputs and strategies for the development of effective, reliable, and safe UVC disinfection systems.
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Affiliation(s)
- Ana Rita Pereira
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Daniel F O Braga
- SpinnerDynamics, Lda., Rua da Junta de Freguesia 194, Escariz, 4540-322 Arouca, Portugal
| | - Mariana Vassal
- SpinnerDynamics, Lda., Rua da Junta de Freguesia 194, Escariz, 4540-322 Arouca, Portugal
| | - Inês B Gomes
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal
| | - Manuel Simões
- LEPABE - Laboratory for Process Engineering, Environment, Biotechnology and Energy, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal; ALiCE - Associate Laboratory in Chemical Engineering, Faculty of Engineering, University of Porto, Rua Dr. Roberto Frias, 4200-465 Porto, Portugal.
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31
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Jia S, Tian Y, Song Y, Zhang H, Kang M, Guo H, Chen H. Effect of NaClO and ClO 2 on the bacterial properties in a reclaimed water distribution system: efficiency and mechanisms. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023:10.1007/s11356-023-27456-6. [PMID: 37178295 DOI: 10.1007/s11356-023-27456-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Subscribe] [Scholar Register] [Received: 11/26/2022] [Accepted: 05/02/2023] [Indexed: 05/15/2023]
Abstract
Extensive application of reclaimed water alleviated water scarcity obviously. Bacterial proliferation in reclaimed water distribution systems (RWDSs) poses a threat to water safety. Disinfection is the most common method to control microbial growth. The present study investigated the efficiency and mechanisms of two widely used disinfectants: sodium hypochlorite (NaClO) and chlorine dioxide (ClO2) on the bacterial community and cell integrity in effluents of RWDSs through high-throughput sequencing (Hiseq) and flow cytometry, respectively. Results showed that a low disinfectant dose (1 mg/L) did not change the bacterial community basically, while an intermediate disinfectant dose (2 mg/L) reduced the biodiversity significantly. However, some tolerant species survived and multiplied in high disinfectant environments (4 mg/L). Additionally, the effect of disinfection on bacterial properties varied between effluents and biofilm, with changes in the abundance, bacterial community, and biodiversity. Results of flow cytometry showed that NaClO disturbed live bacterial cells rapidly, while ClO2 caused greater damage, stripping the bacterial membrane and exposing the cytoplasm. This research will provide valuable information for assessing the disinfection efficiency, biological stability control, and microbial risk management of reclaimed water supply systems.
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Affiliation(s)
- Shichao Jia
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
| | - Yimei Tian
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
| | - Yarong Song
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
| | - Haiya Zhang
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China.
- Institute of Water Ecology and Environment|, Chinese Research Academy of Environmental Science, Beijing, 100012, China.
| | - Mengxin Kang
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
| | - Hao Guo
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
- The Institute of Seawater Desalination and Multipurpose Utilization, MNR (Tianjin), Tianjin, 300192, China
| | - Haolin Chen
- Environmental Science and Engineering, School of Tianjin University, Tianjin, 300072, China
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32
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Liu J, Xia L, Xu Z, Wu W, Gao X, Lin L. Applying lysozyme, alkaline protease, and sodium hypochlorite to reduce bioclogging during managed aquifer recharge: A laboratory study. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 332:117371. [PMID: 36739770 DOI: 10.1016/j.jenvman.2023.117371] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2022] [Revised: 01/08/2023] [Accepted: 01/23/2023] [Indexed: 06/18/2023]
Abstract
Alleviating bacterial-induced clogging is of great importance to improve the efficiency of managed aquifer recharge (MAR). Enzymes (lysozyme and alkaline protease) and sodium hypochlorite (NaClO) are common biological and chemical reagents for inhibiting bacterial growth and activity. To investigate the applicability of these reagents to reduce bioclogging, percolation experiments were performed to simulate a weak alkaline recharge water infiltration through laboratory-scale sand columns, with adding 10 mg/L lysozyme, alkaline protease, and NaClO, respectively. The results showed that, with the addition of lysozyme, alkaline protease, and NaClO, the average clogging rates (the reduced percentages of relative saturated hydraulic conductivity of the sand columns per hour during the percolation experiments) were 0.53%/h, 0.32%/h and 0.06%/h, respectively, which were much lower than that in the control group (0.99%/h). This implied that bioclogging could be alleviated to some extent following the treatments. For further analyzing the mechanisms of the regents on alleviating bioclogging, the bacterial cell amount and extracellular polymeric substances (EPS) concentration were also measured to study the effects of lysozyme, alkaline protease, and NaClO on bacterial growth and EPS secretion. Lysozyme and alkaline protease could disintegrate bacterial EPS by hydrolyzing polysaccharides and proteins, respectively, while they had little effect on the bacterial cell amount. The addition of NaClO significantly decreased the bacterial cell amount (P < 0.05) and thus greatly alleviated bioclogging. Although the lowest average clogging rate was achieved in the NaClO group, it can generate disinfection by-products that are potentially harmful to the environment and human health. Therefore, the biological-based method, i.e., enzyme treatment, could be a promising option for bioclogging control. Our results provide insights for understanding the mechanisms of lysozyme, alkaline protease, and NaClO to alleviate bioclogging, which is of great importance for addressing the clogging problem during MAR activities and achieving groundwater resources sustainable utilization.
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Affiliation(s)
- Jinhui Liu
- College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Lu Xia
- College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China.
| | - Zilin Xu
- College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Wenli Wu
- College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Xiaobing Gao
- College of Earth Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
| | - Lei Lin
- College of Ocean Science and Engineering, Shandong University of Science and Technology, Qingdao, 266590, China
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Xu M, Selvaraj GK, Lu H. Environmental sporobiota: Occurrence, dissemination, and risks. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 869:161809. [PMID: 36702282 DOI: 10.1016/j.scitotenv.2023.161809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Revised: 01/03/2023] [Accepted: 01/20/2023] [Indexed: 06/18/2023]
Abstract
Spore-forming bacteria known as sporobiota are widespread in diverse environments from terrestrial and aquatic habitats to industrial and healthcare systems. Studies on sporobiota have been mainly focused on food processing and clinical fields, while a large amount of sporobiota exist in natural environments. Due to their persistence and capabilities of transmitting virulence factors and antibiotic resistant genes, environmental sporobiota could pose significant health risks to humans. These risks could increase as global warming and environmental pollution has altered the life cycle of sporobiota. This review summarizes the current knowledge of environmental sporobiota, including their occurrence, characteristics, and functions. An interaction network among clinical-, food-related, and environment-related sporobiota is constructed. Recent and effective methods for detecting and disinfecting environmental sporobiota are also discussed. Key problems and future research needs for better understanding and reducing the risks of environmental sporobiota and sporobiome are proposed.
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Affiliation(s)
- Min Xu
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China
| | - Ganesh-Kumar Selvaraj
- Department of Microbiology, St. Peter's Institute of Higher Education and Research, Chennai 600054, Tamil Nadu, India.
| | - Huijie Lu
- Key Laboratory of Environmental Remediation and Ecological Health, Ministry of Education, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou 310058, China; Key Laboratory of Water Pollution Control and Environmental Safety, Zhejiang, China.
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34
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Community Composition and Antibiotic Resistance of Tap Water Bacteria Retained on Filtration Membranes. DIVERSITY 2023. [DOI: 10.3390/d15030427] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/18/2023]
Abstract
Community composition and antibiotic resistance of tap water bacteria are still not known well enough. This study fills the gaps in knowledge regarding this matter. To provide representativeness of collected samples, tap water bacteria were concentrated from huge amounts of water, using filtration membranes monthly during the continuous, semi-annual study, covering winter and spring seasons. Biomass was investigated both using a culture-based method (for total and antibiotic-resistant culturable bacteria counts) and metagenomic DNA sequencing (for taxonomic identification of bacteria). The results showed that bacteria resistant to ceftazidime were the most prevalent among the studied resistance phenotypes, whereas bacteria resistant to amoxicillin, ciprofloxacin, and tetracycline were scarce. On average, 20,059 and 26,200 CFU/mL per month was counted in the winter and spring season, respectively, whereas in terms of antibiotic-resistant bacteria, average counts were 14,270 and 9435 CFU/mL per month in the winter and spring season, respectively. In terms of bacterial community composition, Cyanobacteria, Proteobacteria and Actinobacteria were the most abundant phyla, reaching up to 77.71%, 74.40% and 21.85%, respectively, which is supported by previous studies conducted on the same water supply network and other drinking water distribution systems across the world. No season-dependent variations were observed for culturable antibiotic-resistant bacteria or bacterial community composition. The prevalence of culturable antibiotic-resistant bacteria was not correlated with any of the identified taxa.
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Hu D, Zeng J, Chen J, Lin W, Xiao X, Feng M, Yu X. Microbiological quality of roof tank water in an urban village in southeastern China. J Environ Sci (China) 2023; 125:148-159. [PMID: 36375901 DOI: 10.1016/j.jes.2022.01.036] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Revised: 01/18/2022] [Accepted: 01/24/2022] [Indexed: 06/16/2023]
Abstract
Urban villages are unique residential neighborhoods in urban areas in China. Roof tanks are their main form of water supply, and water quality deterioration might occur in this system because of poor hygienic conditions and maintenance. In this study, water samples were seasonally collected from an urban village to investigate the influence of roof tanks as an additional water storage device on the variation in the microbial community structure and pathogenic gene markers. Water stagnation in the roof tank induced significant decreases in chlorine (p < 0.05), residual chlorine was as low as 0.02 mg/L in spring. Propidium monoazide (PMA)-qPCR revealed a one-magnitude higher level of total viable bacterial concentration in roof tank water samples (2.14 ± 1.81 × 105 gene copies/mL) than that in input water samples (3.57 ± 2.90 × 104 gene copies/mL, p < 0.05), especially in spring and summer. In addition, pathogenic fungi, Mycobacterium spp., and Legionella spp. were frequently detected in the roof tanks. Terminal users might be exposed to higher microbial risk induced by high abundance of Legionella gene marker. Spearman's rank correlation and redundancy analysis showed that residual chlorine was the driving force that promoted bacterial colonization and shaped the microbial community. It is worth noted that the sediment in the pipe will be agitated when the water supply is restored after the water outages, which can trigger an increase in turbidity and bacterial biomass. Overall, the findings provide practical suggestions for controlling microbiological health risks in roof tanks in urban villages.
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Affiliation(s)
- Dong Hu
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jie Zeng
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Jing Chen
- Shitang Community Health Service Center, Xiamen 361026, China
| | - Wenfang Lin
- Key Laboratory of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China
| | - Xinyan Xiao
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Mingbao Feng
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, China
| | - Xin Yu
- College of the Environment and Ecology, Xiamen University, Xiamen 361005, China.
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Tang Y, Wu Z, Zhang Y, Wang C, Ma X, Zhang K, Pan R, Cao Y, Zhou X. Cultivation-dependent and cultivation-independent investigation of O-methylated pollutant-producing bacteria in three drinking water treatment plants. WATER RESEARCH 2023; 231:119618. [PMID: 36706470 DOI: 10.1016/j.watres.2023.119618] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 01/12/2023] [Accepted: 01/15/2023] [Indexed: 06/18/2023]
Abstract
O-methylated pollutants (OMPs) are emerging contaminants in drinking water and mainly produced through bacterial O-methylation. However, the information of OMP-producing bacteria (OMPPB) in drinking water treatment plant (DWTP) is largely unknown so far. In this study, the OMPPB in water samples from three DWTPs (XL, JX and NX) were investigated by using cultivation-dependent and cultivation-independent technologies. Four OMPs were detected and their odor and toxicity risks were assessed. Formation potentials (FPs) of 2,4,6-trichloanisole, 2,3,6-trichloanisole, 2,4,6-tribromoanisole, pentachloroanisole and diclofenac methyl ester were determined in water samples and their values shifted significantly among DWTPs. A most probable number (MPN) method was established to quantify OMPPB numbers and the relationships between total haloanisole FPs (HAFPs) (y) and OMPPB numbers (x) in three DWTPs could be described by the following functions: y = 0.496×0.373 (XL), y = 0.041×0.465 (JX) and y = 0.218×0.237 (NX). Several genera like Bacillus, Ralstonia, Brevundimonas, etc. were newly found OMPPB among the cultivable bacteria, and their OMP products were evaluated in terms of quantity and environment risks (odor, toxicity and bioaccumulation). High-throughput sequencing revealed treatment process was the main driving factor to shape the OMPPB community structures and Mantel test showed HAFP profile was significantly influenced by Mycobacterium and Pelomonas. PICURSt2 analysis discovered four phenolic O-methyltransferases (OMTs) and four carboxylic OMTs which might be responsible for OMP formation. Several strategies were recommended to assess risk and control contamination brought by OMPPB in DWTPs.
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Affiliation(s)
- Yiran Tang
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Zhixuan Wu
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Yanfen Zhang
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Chuanxuan Wang
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Xuelian Ma
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Kejia Zhang
- College of Civil Engineering and Architecture, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Renjie Pan
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Yucheng Cao
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China
| | - Xinyan Zhou
- College of Environment and Resources, College of Carbon Neutral, Zhejiang Agriculture and Forestry University, Hangzhou, Zhejiang 311300, China.
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37
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Ríos-Castro R, Cabo A, Teira E, Cameselle C, Gouveia S, Payo P, Novoa B, Figueras A. High-throughput sequencing as a tool for monitoring prokaryote communities in a wastewater treatment plant. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 861:160531. [PMID: 36470389 DOI: 10.1016/j.scitotenv.2022.160531] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2022] [Revised: 11/23/2022] [Accepted: 11/23/2022] [Indexed: 06/17/2023]
Abstract
In this study, the DNA metabarcoding technique was used to explore the prokaryote diversity and community structure in wastewater collected in spring and winter 2020-2021 as well as the efficiency of the treatment in a wastewater treatment plant (WWTP) in Ría de Vigo (NW Spain). The samplings included raw wastewater from the inlet stream (M1), the discharge water after the disinfection treatment (M3) and mussels used as bioindicators of possible contamination of the marine environment. Significant differences were discovered in the microbiome of each type of sample (M1, M3 and mussels), with 92 %, 45 % and 44 % of exclusive OTUs found in mussel, M3 and M1 samples respectively. Seasonal differences were also detected in wastewater samples, with which abiotic parameters (temperature, pH) could be strongly involved. Bacteria present in raw wastewater (M1) were associated with the human gut microbiome, and therefore, potential pathogens that could be circulating in the population in specific periods were detected (e.g., Arcobacter sp. and Clostridium sp.). A considerable decrease in putative pathogenic organisms from the M1 to M3 wastewater fractions and the scarce presence in mussels (<0.5 % total reads) confirmed the effectiveness of pathogen removal in the wastewater treatment plant. Our results showed the potential of the DNA metabarcoding technique for monitoring studies and confirmed its application in wastewater-based epidemiology (WBE) and environmental contamination studies. Although this technique cannot determine if the infective pathogens are present, it can characterize the microbial communities and the putative pathogens that are circulating through the population (microbiome of M1) and also confirm the efficacy of depuration treatment, which can directly affect the aquaculture sector and even human and veterinary health.
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Affiliation(s)
- Raquel Ríos-Castro
- Marine Research Institute IIM-CSIC, Spanish National Research Council, Eduardo Cabello 6, 36208 Vigo, Spain.
| | - Adrián Cabo
- University of Vigo, BiotecnIA Group, Department of Chemical Engineering, 36310 Vigo, Spain.
| | - Eva Teira
- University of Vigo, Departamento de Ecología y Biología Animal, Centro de Investigación Marina (CIM), Universidad de Vigo, Facultad de Ciencias do Mar, 36310 Vigo, Spain.
| | - Claudio Cameselle
- University of Vigo, BiotecnIA Group, Department of Chemical Engineering, 36310 Vigo, Spain
| | - Susana Gouveia
- University of Vigo, BiotecnIA Group, Department of Chemical Engineering, 36310 Vigo, Spain
| | - Pedro Payo
- GESECO Aguas S.A., Teixugueiras 13, 36212 Vigo, Spain.
| | - Beatriz Novoa
- Marine Research Institute IIM-CSIC, Spanish National Research Council, Eduardo Cabello 6, 36208 Vigo, Spain.
| | - Antonio Figueras
- Marine Research Institute IIM-CSIC, Spanish National Research Council, Eduardo Cabello 6, 36208 Vigo, Spain.
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Ye C, Zhang K, Wu X, Wan K, Cai WF, Feng M, Yu X. Uncovering novel disinfection mechanisms of solar light/periodate system: The dominance of singlet oxygen and metabolomic insights. JOURNAL OF HAZARDOUS MATERIALS 2023; 443:130177. [PMID: 36308932 DOI: 10.1016/j.jhazmat.2022.130177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/02/2022] [Revised: 09/30/2022] [Accepted: 10/09/2022] [Indexed: 06/16/2023]
Abstract
Disinfection plays an essential role in waterborne pathogen control and disease prevention, especially during the COVID-19 pandemic. Catalyst-free solar light/periodate (PI) system has recently presented great potential in water disinfection, whereas the in-depth chemical and microbiological mechanisms for efficient bacterial inactivation remain unclear. Our work delineated firstly the critical role of singlet oxygen, instead of reported hydroxyl radicals and superoxide radicals, in dominating bacterial inactivation by the PI/simulated sunlight (SSL) system. Multi-evidence demonstrated the prominent disinfection performance of this system for Staphylococcus aureus in terms of culturability (> 6 logs CFU), cellular integrity, and metabolic activity. Particularly, the excellent intracellular DNA removal (> 95%) indicated that PI/SSL system may function as a selective disinfection strategy to diminish bacterial culturability without damaging the cell membrane. The PI/SSL system could also effectively inhibit bacterial regrowth for > 5 days and horizontal gene transfer between E. coli genera. Nontargeted metabolomic analysis suggested that PI/SSL system inactivated bacteria by triggering the accumulation of intracellular reactive oxygen species and the depletion of reduced glutathione. Additionally, the PI/SSL system could accomplish simultaneous micropollutant removal and bacterial inactivation, suggesting its versatility in water decontamination. Overall, this study deciphers more comprehensive antibacterial mechanisms of this environmentally friendly disinfection system, facilitating the technical development and application of the selective disinfection strategy in environmental pathogen control.
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Affiliation(s)
- Chengsong Ye
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Kaiting Zhang
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xu Wu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Kun Wan
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Wei-Feng Cai
- Xiamen Cancer Center, The First Affiliated Hospital of Xiamen University, Xiamen 361009, China
| | - Mingbao Feng
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China
| | - Xin Yu
- College of the Environment & Ecology, Xiamen University, Xiamen 361102, China.
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Lu YW, Liang XX, Wang CY, Chen D, Liu H. Synergistic nanowire-assisted electroporation and chlorination for inactivation of chlorine-resistant bacteria in drinking water systems via inducing cell pores for chlorine permeation. WATER RESEARCH 2023; 229:119399. [PMID: 36462257 DOI: 10.1016/j.watres.2022.119399] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/25/2022] [Accepted: 11/19/2022] [Indexed: 06/17/2023]
Abstract
The widespread use of chlorination (Cl2) in drinking water systems causes the selection of chlorine-resistant bacteria commonly with dense extracellular polymeric substance (EPS) against chlorine permeation, posing significant threat to public health. Herein, a nanowire-assisted electroporation (EP) via locally enhanced electric field was combined with Cl2 to construct the synergistic EP/Cl2 disinfection, with the purposes of inducing cell pores for chlorine permeation and bacterial inactivation. The synergistic effects of EP/Cl2 were observed for inactivation of chlorine-resistant Bacillus cereus (G+, 304 μg DOC-EPS/109 CFU) and Aeromonas media (G-, 35.8 μg), and chlorine-sensitive Escherichia coli (G-, 5.1 μg) that were frequent occurrence in drinking water systems. The EP/Cl2 enabled above 6 log B. cereus inactivation (undetectable live bacteria) at 1.5 V-EP and 0.9 mg/L-Cl2, which was much higher than the individual EP (1.11 log) and Cl2 (1.13 log) disinfection. The cell membrane integrity, intracellular free chlorine levels, and morphology analyses revealed that the electroporation-induced pores on cell wall/membrane destructed the bound EPS barrier for chlorine permeation, and the pore sizes were further enlarged by chlorine oxidation, hence facilitating bacterial inactivation via destroying the cell structures. The excellent disinfection performance for tap water and lake water also suggested its sound application potentials.
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Affiliation(s)
- Ying-Wen Lu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Xiang-Xing Liang
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Chen-Yang Wang
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Da Chen
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China
| | - Hai Liu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou, 510632, PR China.
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40
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Jing Z, Lu Z, Zhao Z, Cao W, Wang W, Ke Y, Wang X, Sun W. Molecular ecological networks reveal the spatial-temporal variation of microbial communities in drinking water distribution systems. J Environ Sci (China) 2023; 124:176-186. [PMID: 36182128 DOI: 10.1016/j.jes.2021.10.017] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 10/12/2021] [Accepted: 10/12/2021] [Indexed: 06/16/2023]
Abstract
Microbial activity and regrowth in drinking water distribution systems is a major concern for water service companies. However, previous studies have focused on the microbial composition and diversity of the drinking water distribution systems (DWDSs), with little discussion on microbial molecular ecological networks (MENs) in different water supply networks. MEN analysis explores the potential microbial interaction and the impact of environmental stress, to explain the characteristics of microbial community structures. In this study, the random matrix theory-based network analysis was employed to investigate the impact of seasonal variation including water source switching on the networks of three DWDSs that used different disinfection methods. The results showed that microbial interaction varied slightly with the seasons but was significantly influenced by different DWDSs. Proteobacteria, identified as key species, play an important role in the network. Combined UV-chlorine disinfection can effectively reduce the size and complexity of the network compared to chlorine disinfection alone, ignoring seasonal variations, which may affect microbial activity or control microbial regrowth in DWDSs. This study provides new insights for analyzing the dynamics of microbial interactions in DWDSs.
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Affiliation(s)
- Zibo Jing
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China; School of Environment, Tsinghua University, Beijing 100084, China
| | - Zedong Lu
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Zhinan Zhao
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China
| | - Wenfeng Cao
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Weibo Wang
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Yanchu Ke
- State Key Joint Laboratory of Environmental Simulation and Pollution Control, College of Environmental Sciences and Engineering, Peking University, Beijing 100871, China
| | - Xiaohui Wang
- Beijing Engineering Research Center of Environmental Material for Water Purification, College of Chemical Engineering, Beijing University of Chemical Technology, Beijing 100029, China.
| | - Wenjun Sun
- School of Environment, Tsinghua University, Beijing 100084, China; Research Institute for Environmental Innovation (Suzhou) Tsinghua, Suzhou 215163, China.
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Mosaka TBM, Unuofin JO, Daramola MO, Tizaoui C, Iwarere SA. Inactivation of antibiotic-resistant bacteria and antibiotic-resistance genes in wastewater streams: Current challenges and future perspectives. Front Microbiol 2023; 13:1100102. [PMID: 36733776 PMCID: PMC9888414 DOI: 10.3389/fmicb.2022.1100102] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2022] [Accepted: 12/29/2022] [Indexed: 01/17/2023] Open
Abstract
The discovery of antibiotics, which was once regarded as a timely medical intervention now leaves a bitter aftertaste: antimicrobial resistance (AMR), due to the unregulated use of these compounds and the poor management receiving wastewaters before discharge into pristine environments or the recycling of such treated waters. Wastewater treatment plants (WWTPs) have been regarded a central sink for the mostly unmetabolized or partially metabolised antibiotics and is also pivotal to the incidence of antibiotic resistance bacteria (ARBs) and their resistance genes (ARGs), which consistently contribute to the global disease burden and deteriorating prophylaxis. In this regard, we highlighted WWTP-antibiotics consumption-ARBs-ARGs nexus, which might be critical to understanding the epidemiology of AMR and also guide the precise prevention and remediation of such occurrences. We also discovered the unsophistication of conventional WWTPs and treatment techniques for adequate treatment of antibiotics, ARBs and ARGs, due to their lack of compliance with environmental sustainability, then ultimately assessed the prospects of cold atmospheric plasma (CAP). Herein, we observed that CAP technologies not only has the capability to disinfect wastewater polluted with copious amounts of chemicals and biologicals, but also have a potential to augment bioelectricity generation, when integrated into bio electrochemical modules, which future WWTPs should be retrofitted to accommodate. Therefore, further research should be conducted to unveil more of the unknowns, which only a snippet has been highlighted in this study.
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Affiliation(s)
- Thabang B. M. Mosaka
- Department of Chemical Engineering, Faculty of Engineering, Built Environment and Information Technology, University of Pretoria, Pretoria, South Africa
| | - John O. Unuofin
- Department of Chemical Engineering, Faculty of Engineering, Built Environment and Information Technology, University of Pretoria, Pretoria, South Africa
| | - Michael O. Daramola
- Department of Chemical Engineering, Faculty of Engineering, Built Environment and Information Technology, University of Pretoria, Pretoria, South Africa
| | - Chedly Tizaoui
- Water and Resources Recovery Research Lab, Department of Chemical Engineering, Faculty of Science and Engineering, Swansea University, Swansea, United Kingdom
| | - Samuel A. Iwarere
- Department of Chemical Engineering, Faculty of Engineering, Built Environment and Information Technology, University of Pretoria, Pretoria, South Africa,*Correspondence: Samuel A. Iwarere, ✉
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Zhao HX, Zhang TY, Wang H, Hu CY, Tang YL, Xu B. Occurrence of fungal spores in drinking water: A review of pathogenicity, odor, chlorine resistance and control strategies. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 853:158626. [PMID: 36087680 DOI: 10.1016/j.scitotenv.2022.158626] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2022] [Revised: 08/17/2022] [Accepted: 09/05/2022] [Indexed: 06/15/2023]
Abstract
Fungi in drinking water have been long neglected due to the lack of convenient analysis methods, widely accepted regulations and efficient control strategies. However, in the last few decades, fungi in drinking water have been widely recognized as opportunity pathogens that cause serious damage to the health of immune-compromised individuals. In drinking water treatment plants, fungal spores are more resistant to chlorine disinfection than bacteria and viruses, which can regrow in drinking water distribution systems and subsequently pose health threats to water consumers. In addition, fungi in drinking water may represent an ignored source of taste and odor (T&O). This review identified 74 genera of fungi isolated from drinking water and presented their detailed taxonomy, sources and biomass levels in drinking water systems. The typical pathways of exposure of water-borne fungi and the main effects on human health are clarified. The fungi producing T&O compounds and their products are summarized. Data on free chlorine or monochloramine inactivation of fungal spores and other pathogens are compared. At the first time, we suggested four chlorine-resistant mechanisms including aggregation to tolerate chlorine, strong cell walls, cellular responses to oxidative stress and antioxidation of melanin, which are instructive for the future fungi control attempts. Finally, the inactivation performance of fungal spores by various technologies are comprehensively analyzed. The purpose of this study is to provide an overview of fungi distribution and risks in drinking water, provide insight into the chlorine resistance mechanisms of fungal spores and propose approaches for the control of fungi in drinking water.
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Affiliation(s)
- Heng-Xuan Zhao
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Tian-Yang Zhang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Hong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Chen-Yan Hu
- College of Environmental and Chemical Engineering, Shanghai University of Electric Power, Shanghai 200090, PR China
| | - Yu-Lin Tang
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Bin Xu
- State Key Laboratory of Pollution Control and Resource Reuse, Key Laboratory of Yangtze Water Environment, Ministry of Education, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China.
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Miao X, Han X, Liu C, Bai X. Intrinsic chlorine resistance of bacteria modulated by glutaminyl-tRNA biosynthesis in drinking water supply systems. CHEMOSPHERE 2022; 308:136322. [PMID: 36084827 DOI: 10.1016/j.chemosphere.2022.136322] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2022] [Revised: 08/30/2022] [Accepted: 09/01/2022] [Indexed: 06/15/2023]
Abstract
The existence of chlorine-resistant bacteria (CRB) in drinking water supply systems (DWSSs) results in significant challenges to the biological security of drinking water. However, little is known about the intrinsic chlorine-resistant molecular metabolic mechanism of bacteria in DWSSs. This research explored the microbial interactions and the key metabolic pathways that modulate the chlorine resistance of bacteria in full-scale chloraminated DWSSs. The dominant CRB, including Bdellovibrio, Bradyrhizobium, Peredibacter, Sphingomonas, and Hydrogenophaga, strongly interacted with each other to maintain basic metabolism. A total of 4.21% of the bacterial metabolic pathways were key and specific to chlorine-resistant bacteria. Glutaminyl-tRNA biosynthesis was the dominant metabolic pathway of CRB in the target DWSSs. After chloramine disinfection, the relative abundance of glutamate-tRNA ligase (GlnRS) and the related orthologous genes increased by 10.11% and 14.58%, respectively. The inactivation rate of the GlnRS overexpression strain (81.40%) was lower than that of the wild-type strain (90.11%) after exposure to chloramine. Meanwhile, the growth rate of the GlnRS overexpression strain was higher than that of the wild-type strain. Glutaminyl-tRNA biosynthesis can enhance chlorine resistance in DWSSs.
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Affiliation(s)
- Xiaocao Miao
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China; State Key Laboratory of Oncogenes and Related Genes, Shanghai Cancer Institute, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai, PR China
| | - Xue Han
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Chenxu Liu
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China
| | - Xiaohui Bai
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic & Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, PR China.
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Mao Y, Chen Z, Zhang ZW, Xue S, Lu Y, Shi Q, Cao KF, Chen XW, Wu YH, Hu HY. Comparison of the disinfection efficacy between ferrate(VI) and chlorine in secondary effluent. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 848:157712. [PMID: 35908691 DOI: 10.1016/j.scitotenv.2022.157712] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2022] [Revised: 07/19/2022] [Accepted: 07/26/2022] [Indexed: 05/26/2023]
Abstract
Disinfection is essential for the microbial safety of reclaimed water. Traditional chlorine disinfection leads to secondary problems such as disinfection by-products and chlorine-resistant bacteria. Ferrate (Fe(VI)) is a novel green disinfectant. However, research on the disinfection characteristics of Fe(VI) remains insufficient. This study compared the disinfection efficacy between Fe(VI) and chlorine in secondary effluent, including the inactivation efficiency of coliforms and heterotrophic bacteria and the control effect on typical chlorine-resistant bacteria. The results showed that Fe(VI) was more effective than chlorine in inactivating Escherichia coli and total coliforms at low doses, whereas chlorine was more effective than Fe(VI) in inactivating heterotrophic bacteria. A severe trailing phenomenon was observed in Fe(VI) disinfection. Based on bacterial community structure analysis, Fe(VI) was also found to be capable of controlling the relative abundance of some chlorine-resistant bacteria such as Sphingomonas, Bacillus, Mycobacterium and Legionella except for Pseudomonas. The results of this study could have implications in evaluating Fe(VI) disinfection ability and optimizing Fe(VI) dosing for disinfection.
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Affiliation(s)
- Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China.
| | - Zi-Wei Zhang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Song Xue
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Ke-Fan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Xiao-Wen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), Beijing Laboratory for Environmental Frontier Technologies, School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Suzhou 215163, PR China.
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Chen X, Chen Z, Liu H, Huang N, Mao Y, Cao K, Shi Q, Lu Y, Hu HY. Synergistic effects of UV and chlorine in bacterial inactivation for sustainable water reclamation and reuse. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 845:157320. [PMID: 35839898 DOI: 10.1016/j.scitotenv.2022.157320] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/18/2022] [Revised: 06/30/2022] [Accepted: 07/08/2022] [Indexed: 06/15/2023]
Abstract
Disinfection is a necessity in water and wastewater treatment and reclamation. This study examined the inactivation of a disinfectant resistant but widely existed opportunistic pathogen in reclaimed water, Staphylococcus aureus (S. aureus), by sequential UV and chlorine disinfection or simultaneous UV and chlorine disinfection (UV/Cl). It was identified that UV/Cl greatly promoted the inactivation efficacy and inhibited photoreactivation of S. aureus by the generation of free radicals (i.e. OH and Cl), which reached a 7-log10 reduction at UV and chlorine doses of 18 mJ/cm2 and 2 mg-Cl/L, respectively. The changes of bacterial viability and morphology and the increase of extracellular ATP concentration confirmed the enhancement of cell membranes damages (>21.4 %) due to free radicals generated in UV/Cl process, which caused a dramatic reduction in metabolic activity and suppressed the photoreactivation. Furthermore, this study demonstrated that UV/Cl effectively removed heterotrophic plate count bacteria and aromatic organic fluorophores in reclaimed water samples. This study is of significant theoretical and applicable importance in guaranteeing safe microbial levels for water reclamation and reuse.
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Affiliation(s)
- Xiaowen Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Hai Liu
- School of Environment, Guangzhou Key Laboratory of Environmental Exposure and Health, and Guangdong Key Laboratory of Environmental Pollution and Health, Jinan University, Guangzhou 510632, PR China
| | - Nan Huang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yu Mao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Kefan Cao
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Qi Shi
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China
| | - Yun Lu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, PR China
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Radwan EK, Rashdan HRM, Hemdan BA, Koryam AA, El-Naggar ME. A dual-functional sulfone biscompound containing 1,2,3-triazole moiety for decolorization and disinfection of contaminated water. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2022; 29:77238-77252. [PMID: 35676578 PMCID: PMC9581830 DOI: 10.1007/s11356-022-20932-5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2022] [Accepted: 05/13/2022] [Indexed: 05/28/2023]
Abstract
Water decontamination from toxic dyes and pathogenic microorganisms is critical for life on Earth. Herein, we report the synthesis of sulfone biscompound containing 1,2,3-triazole moiety and evaluation of its dye decolorization and biocidal and disinfection efficiencies. The decolorization efficiency was tested under different experimental conditions, while the biocidal action was examined against various types of waterborne pathogens, and the disinfection of some pathogenic microbes was executed in artificially contaminated water. The findindgs illustrated that the solution initial pH (pHi) affected the decolorization efficiency significantly. About complete removal of 10 mg/L malachite green (MG) dye was achieved after 10 min using 3 g/L of the sulfone biscompound at pHi 6. The pseudo-second-order equation suited the adsorption kinetics accurately, while the equilibrium data was suited by Langmuir isotherm model. Electrostatic, n-π, and π-π interactions brought about the adsorption of MG onto the sulfone biscompound. The biocidal results indicated that the sulfone biscompound had a powerful antibacterial potential against the tested bacterial species. Likewise, the distinction trail revealed that after 70-90 min of direct contact with an effective dose, the tested pathogens could be completely eliminated (6-log reduction). Overall, the newly synthesized sulfone biscompound can efficiently remove cationic dyes and disinfect contaminated water.
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Affiliation(s)
- Emad K Radwan
- Water Pollution Research Department, National Research Centre, 33 El Buhouth St, Dokki, Giza, 12622, Egypt.
| | - Huda R M Rashdan
- Chemistry of Natural and Microbial Products Department, Pharmaceutical and Drug Industries Research Institute, National Research Centre, 33 El Buhouth St, Dokki, Giza, 12622, Egypt
| | - Bahaa A Hemdan
- Water Pollution Research Department, National Research Centre, 33 El Buhouth St, Dokki, Giza, 12622, Egypt
| | - Asmaa A Koryam
- Water Pollution Research Department, National Research Centre, 33 El Buhouth St, Dokki, Giza, 12622, Egypt
| | - Mehrez E El-Naggar
- Institute of Textile Research and Technology, National Research Centre, 33 El Bohouth St, Dokki, Giza, 12622, Egypt.
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Coleine C, Delgado-Baquerizo M. Unearthing terrestrial extreme microbiomes for searching terrestrial-like life in the Solar System. Trends Microbiol 2022; 30:1101-1115. [PMID: 35568658 DOI: 10.1016/j.tim.2022.04.002] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/03/2022] [Accepted: 04/11/2022] [Indexed: 01/13/2023]
Abstract
The possibility of life elsewhere in the universe has fascinated humankind for ages. To the best of our knowledge, life, as we know it, is limited to planet Earth; yet current investigation suggests that life might be more common than previously thought. In this review, we explore extreme terrestrial analogue environments in the search for some notable examples of extreme organisms, including overlooked microbial groups such as viruses, fungi, and protists, associated with limits of life on Earth. This knowledge is integral to provide the foundational principles needed to predict what sort of Earth-like organisms we might find in the Solar System and beyond, and to understand the future and origins of life on Earth.
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Affiliation(s)
- Claudia Coleine
- Department of Ecological and Biological Sciences, University of Tuscia, 01100 Viterbo, Italy.
| | - Manuel Delgado-Baquerizo
- Laboratorio de Biodiversidad y Funcionamiento Ecosistémico. Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNAS), CSIC, Av. Reina Mercedes 10, E-41012, Sevilla, Spain; Unidad Asociada CSIC-UPO (BioFun). Universidad Pablo de Olavide, 41013 Sevilla, Spain.
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48
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Wang HB, Wu YH, Wang WL, Chen Z, Chen GQ, Luo LW, Xue S, Tong X, Zhang ZW, Ikuno N, Ishii K, Hu HY. Comparison of disinfection-residual-bacteria (DRB) after seven different kinds of disinfection: Biofilm formation, membrane fouling and mechanisms. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 844:157079. [PMID: 35779720 DOI: 10.1016/j.scitotenv.2022.157079] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2022] [Revised: 06/16/2022] [Accepted: 06/27/2022] [Indexed: 06/15/2023]
Abstract
Membrane fouling is the Achilles' heel of the reverse osmosis (RO) system for high-quality reclaimed water production. Previous studies have found that after the significant selection effect of traditional disinfection, the remaining disinfection-residual bacteria (DRB) may possess more severe biofouling potentials. To provide more constructive advice for the prevention of biofouling, we compared the RO membrane fouling characteristics of DRB after using five commonly used disinfection methods (NaClO, NH2Cl, ClO2, UV, and O3) and two novel disinfection methods (K2FeO4 and the flow-through electrode system (FES)). Compared with the control group (undisinfected, 21.1 % flux drop), the UV-DRB biofilm aggravated biofouling of the RO membrane (23.4 % flux drop), while the FES, K2FeO4, and NH2Cl treatments showed less severe biofouling, with final flux drops of 6.9 %, 8.1 %, and 8.1 %, respectively. Adenosine triphosphate (ATP) was found to be a capable indicator for predicting the biofouling potential of DRB. Systematic analysis showed that the thickness and density of the DRB biofilms were most closely related to the different fouling degree of RO membranes. Moreover, the relative abundance of bacteria with higher extracellular polymeric substance (EPS) secretion levels, such as Pseudomonas and Sphingomonas, was found closely related with the biofouling degree of RO membranes.
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Affiliation(s)
- Hao-Bin Wang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Yin-Hu Wu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China.
| | - Wen-Long Wang
- Key Laboratory of Microorganism Application and Risk Control of Shenzhen, Institute of Environment and Ecology, Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, PR China
| | - Zhuo Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Gen-Qiang Chen
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Li-Wei Luo
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Song Xue
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Xin Tong
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Zi-Wei Zhang
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Beijing Laboratory for Environmental Frontier Technologies, Beijing 100084, PR China
| | - Nozomu Ikuno
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Kazuki Ishii
- Kurita Water Industries Ltd., Nakano-ku, Tokyo 164-0001, Japan
| | - Hong-Ying Hu
- Environmental Simulation and Pollution Control State Key Joint Laboratory, State Environmental Protection Key Laboratory of Microorganism Application and Risk Control (SMARC), School of Environment, Tsinghua University, Beijing 100084, PR China; Research Institute for Environmental Innovation (Suzhou), Tsinghua, Jiangsu, Suzhou 215163, PR China
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Zhong D, Zhou Z, Ma W, Ma J, Feng W, Li J, Du X. Antibiotic enhances the spread of antibiotic resistance among chlorine-resistant bacteria in drinking water distribution system. ENVIRONMENTAL RESEARCH 2022; 211:113045. [PMID: 35248560 DOI: 10.1016/j.envres.2022.113045] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/23/2022] [Revised: 02/17/2022] [Accepted: 02/25/2022] [Indexed: 06/14/2023]
Abstract
The extensive use of antibiotics leads to the occurrences of antibiotic resistance genes (ARGs) in aquatic environment. As an emerging environmental pollutant, its pollution in aquatic environment has aroused widespread concern. However, the residues of antibiotics and antibiotic resistance genes in drinking water distribution system were barely reported up to now. Here, we studied the correlation and coordination between chlorine resistance mechanism and antibiotic resistance mechanism of chlorine-resistant bacteria. Antibiotics induce the resistance of chlorine-resistant bacteria (CRB) to NaClO, so that low-dose disinfectants can not inactivate CRB. We put forward a strategy to control the growth of CRB by controlling the concentration of biodegradable dissolved organic carbon (BDOC) in the front section of the water network. Moreover, We screened two strains of chlorine-resistant bacteria with different antibiotic resistance after mixed culture, the results showed that antibiotic resistance could spread horizontally among different kinds of bacteria. Then, the non-pathogenic bacteria can be used as a carrier, causing the pathogen to become resistant to antibiotic, and ultimately pose harm to human health. Generally, the antibiotic, antibiotic resistant genes, and the chlorine disinfectants added in water treatment plants will interact with bacteria in the water supply pipe network, which causes pollution to drinking water.
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Affiliation(s)
- Dan Zhong
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Ziyi Zhou
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Wencheng Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Jun Ma
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Weinan Feng
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Jinxin Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
| | - Xuan Du
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, 150090, China
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Cai G, Liu T, Zhang J, Song H, Jiang Q, Zhou C. Control for chlorine resistant spore forming bacteria by the coupling of pre-oxidation and coagulation sedimentation, and UV-AOPs enhanced inactivation in drinking water treatment. WATER RESEARCH 2022; 219:118540. [PMID: 35550966 DOI: 10.1016/j.watres.2022.118540] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/04/2022] [Revised: 04/06/2022] [Accepted: 05/02/2022] [Indexed: 06/15/2023]
Abstract
Spore forming bacteria (SFB) are strongly chlorine resistant. Their presence in drinking water may cause diseases and pose threat to public health. Three SFB strains, i.e. Bacillus alvei, Bacillus cereus, and Lysinibacillus fusiformis, were isolated and identified from the finished water of a drinking water treatment plant where bacteria colonies occasionally reached the limit value. Due to their chlorine resistance, a SFB control strategy coupling pre-oxidation, coagulation sedimentation, and UV-AOPs inactivation in water treatment process was studied in lab scale. Five minutes pre-oxidation treatment by applying Cl2 and ClO2 induced remarkable spore transformation. Longer pre-oxidation exposure time didn't have apparent improvement. Cl2 and ClO2 dosages of 0.9 mg/L and 0.5 mg/L were suggested, respectively. The formed spores can be efficiently removed by the following coagulation sedimentation treatment. At a suggested dosage combination of 20 mg/L PAC and 0.08 mg/L PAM, spore removal efficiency reached about 3.15-lg. Comparing to applying sole UV irradiation, enhanced UV inactivation by adding 0.1 mM H2O2, or Cl2, or peroxymonosulfate (PMS) substantially improved the inactivation of the most chlorine resistant SFB strain, Lysinibacillus fusiformis. UV-AOPs stably achieved 2-lg inactivation rate at UV dosage of 40 mJ/cm2. UV/H2O2, UV/Cl2 and UV/PMS inactivation kinetically enhanced 1.20 times, 1.36 times and 1.91 times over sole UV irradiation. Intracellular DNA and ATP leakages were detected, and remarkable damages of Lysinibacillus fusiformis cells' surface and ultrastructure were observed. These findings evidenced cell wall and cell membrane destructions, guaranteeing substantial SFB cells inactivation. This study was carried out based on three SFB strains isolated from a finished water, and common engineering practical operations. By providing engineeringly relevant references, the outcomes obtained would be helpful for dealing with SFB outbreak risk in drinking water treatment.
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Affiliation(s)
- Guangqiang Cai
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China; Shenzhen Water Affairs (Group) Co., Ltd., Shenzhen, 518031, China
| | - Tongzhou Liu
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China.
| | - Jinsong Zhang
- Harbin Institute of Technology, Shenzhen, Shenzhen, 518055, China; Shenzhen Water Affairs (Group) Co., Ltd., Shenzhen, 518031, China
| | - Haoran Song
- Research Center for Eco-environmental Engineering, Dongguan University of Technology, Dongguan, 523808, China
| | - Qijun Jiang
- Shenzhen Shen Shui Bao An Water Affairs (Group) Co., Ltd., Shenzhen, 518133, China
| | - Chang Zhou
- School of Civil Engineering, Guangzhou University, Guangzhou, 510006, China
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