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Tian H, Wang L, Zhu X, Zhang M, Li L, Liu Z, Abolfathi S. Biodegradation of microplastics derived from controlled release fertilizer coating: Selective microbial colonization and metabolism in plastisphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 920:170978. [PMID: 38365031 DOI: 10.1016/j.scitotenv.2024.170978] [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: 12/30/2023] [Revised: 02/05/2024] [Accepted: 02/13/2024] [Indexed: 02/18/2024]
Abstract
Coated controlled-release fertilizers (CRFs) are widely used in agriculture, and the persistent presence of residual polymer coating has raised environmental concerns. This study investigates the underlying degradation dynamics of microplastics (MPs) derived from three typical materials used in CRFs, including polyethylene (PE), epoxy (EP), and polyurethane (PU), through a soil degradation test. The formation of surface biofilm, the succession process, and metabolic characteristics of microbial community are revealed by laser scanning confocal microscope, 16S rRNA sequencing, and non-targeted metabolomics analysis. The weight loss rates of PE, EP, and PU after 807 days of degradation were 16.70 %, 2.79 %, and 4.86 %, respectively. Significant secondary MPs were produced with tears and holes appeared in the coating cross sections and pyrolysis products were produced such as ethers, acids, and esters for PE; alkanes, olefins and their branched-chain derivatives for EP; and short-chain fatty acids and benzene molecules for PU. The coating surface selectively recruited the bacteria of Chujaibacter and Ralstonia and fungus of Fusarium and Penicillium, forming biofilm composed of lipids, proteins, and living cells. The metabolism of amino acids and polymers was enhanced to protect against MP-induced stress. The metabolites or intermediates of organic acids and derivatives, oxygen-contained organic compounds, and benzenoids on CRF surface increased significantly compared with soil, but there were no significant differences among different coating types. This study provides insights to the underlying mechanisms of biodegradation and microenvironmental changes of MPs in soil.
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Affiliation(s)
- Hongyu Tian
- National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Recourses and Environment, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Lingyun Wang
- National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Recourses and Environment, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Xiaofan Zhu
- Faculty of Engineering, University of Bristol, Bristol BS8 1TH, United Kingdom
| | - Min Zhang
- National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Recourses and Environment, Shandong Agricultural University, Taian, Shandong 271018, China
| | - Lei Li
- Department of Chemistry, Western Kentucky University, Bowling Green, KY 42101, United States
| | - Zhiguang Liu
- National Engineering Research Center for Efficient Utilization of Soil and Fertilizer Resources, College of Recourses and Environment, Shandong Agricultural University, Taian, Shandong 271018, China.
| | - Soroush Abolfathi
- School of Engineering, University of Warwick, Coventry CV47AL, United Kingdom
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Feng W, Zhang Q, Li J, Duan C, Peng Y. Novel anammox granules formation from conventional activated sludge for municipal wastewater treatment through flocs management. BIORESOURCE TECHNOLOGY 2024; 396:130384. [PMID: 38281548 DOI: 10.1016/j.biortech.2024.130384] [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: 11/14/2023] [Revised: 01/22/2024] [Accepted: 01/23/2024] [Indexed: 01/30/2024]
Abstract
The direct integration of anammox process into municipal wastewater treatment has caused widespread concern, but the lack of anammox seeds limited its real application. This study successfully cultivated anammox granules (322.0 μm) from conventional activated sludge treating municipal wastewater. Through ultra-low floc sludge retention times of 8d, nitrifiers on flocs were eliminated and partial nitrification was realized. Furthermore, highly bacteria-enriched granules were initially formed, with Nitrosomonas and Ca. Competibacter 4-fold higher than that of flocs. Specific staining results revealed the microbial interaction with Ca. Brocadia, considering that Ca. Competibacter and Nitrosomonas correspondingly identified in the inner and outer layers of granules. The percentage of Ca. Brocadia present on the granules increased substantially from 0.0 % to 3.0 %, accompanied by a nitrogen removal rate of 0.3 kg·m-3·d-1. Our findings revealed a valuable reference for the anammox bacteria in-situ enrichment under mainstream conditions, which provides theoretical guidance for anammox-based processes practical application.
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Affiliation(s)
- Wanyi Feng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Qiong Zhang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Jialin Li
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Chenxue Duan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China.
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Xu J, Gao Y, Bi X, Li L, Xiang W, Liu S. Positive effects of lignocellulose on the formation and stability of aerobic granular sludge. Front Microbiol 2023; 14:1254152. [PMID: 37670989 PMCID: PMC10475587 DOI: 10.3389/fmicb.2023.1254152] [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: 07/06/2023] [Accepted: 07/31/2023] [Indexed: 09/07/2023] Open
Abstract
Introduction Lignocellulose is one of the major components of particulate organic matter in sewage, which has a significant influence on biological wastewater treatment process. However, the effect of lignocellulose on aerobic granular sludge (AGS) system is still unknown. Methods In this study, two reactors were operated over 5 months to investigate the effect of lignocellulose on granulation process, structure stability and pollutants removal of AGS. Results and discussion The results indicated that lignocellulose not only promoted the secretion of tightly bound polysaccharide in extracellular polymeric substances, but also acted as skeletons within granules, thereby facilitating AGS formation, and enhancing structural strength. Lignocellulose imposed little effect on the removal efficiency of pollutants, with more than 95, 99, and 92% of COD, NH4+-N, and PO43--P were removed in both reactors. However, it did exhibit a noticeable influence on pollutants conversion processes. This might be due to that the presence of lignocellulose promoted the enrichment of functional microorganisms, including Candidatus_Accumulibacter, Candidatus_Competibacter, Nitrosomonas, and Nitrospira, etc. These findings might provide valuable insights into the control strategy of lignocellulose in practical AGS systems.
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Affiliation(s)
- Jie Xu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Yuan Gao
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Xuejun Bi
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Lin Li
- Key Laboratory of the Three Gorges Reservoir Region’s Eco-Environment, Ministry of Education, College of Environment and Ecology, Chongqing University, Chongqing, China
| | - Wenjuan Xiang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
| | - Shichang Liu
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, China
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Zhang W, Li Q, Yang Y, Yu Y, Li S, Liu J, Xiao Y, Wen Y, Wang Q, Lei N, Gu P. Joint toxicity mechanisms of perfluorooctanoic acid and sulfadiazine on submerged macrophytes and periphytic biofilms. JOURNAL OF HAZARDOUS MATERIALS 2023; 458:131910. [PMID: 37390681 DOI: 10.1016/j.jhazmat.2023.131910] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 06/19/2023] [Accepted: 06/20/2023] [Indexed: 07/02/2023]
Abstract
Hazardous chemicals, such as perfluoroalkyl substances (PFASs) and antibiotics, coexist in aquatic environments and pose a severe threat to aquatic organisms. However, research into the toxicity of these pollutants on submerged macrophytes and their periphyton is still limited. To assess their combined toxicity, Vallisneria natans (V. natans) was exposed to perfluorooctanoic acid (PFOA) and sulfadiazine (SD) at environmental concentrations. Photosynthetic parameters such as chlorophyll a, chlorophyll b, total chlorophyll, and carotenoids were lower in the SD exposure group, indicating that SD had a significant effect on the photosynthesis of aquatic plants. Single and combined exposures effectively induced antioxidant responses, with increases in superoxide dismutase, peroxidase activities, and ribulose-1,5-bisphosphate carboxylase concentrations, as well as malondialdehyde content. Accordingly, antagonistic toxicity was assessed between PFOA and SD. Furthermore, metabolomics revealed that V. natans improved stress tolerance through changes in enoic acid, palmitic acid, and palmitoleoyloxymyristic acid related to the fatty acid metabolism pathway responding to the coexisting pollutants. Additionally, PFOA and SD in combination induced more effects on the microbial community of biofilm. The alternation of α- and β-D-glucopyranose polysaccharides and the increased content of autoinducer peptides and N-acylated homoserine lactones indicated that PFOA and SD changed the structure and function of biofilm. These investigations provide a broader perspective and comprehensive analysis of the responses of aquatic plants and periphyton biofilms to PFAS and antibiotics in the environment.
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Affiliation(s)
- Weizhen Zhang
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Qi Li
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China.
| | - Yixia Yang
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Yangjinzhi Yu
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Shuang Li
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Jing Liu
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Yunxing Xiao
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Yuelin Wen
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | | | - Ningfei Lei
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Peng Gu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China
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Shi P, Du M, Wang J. Effect of Alcaligenes sp. on corrosion behavior of X65 steel in simulated offshore oilfield-produced water. Front Microbiol 2023; 14:1127858. [PMID: 37007476 PMCID: PMC10063886 DOI: 10.3389/fmicb.2023.1127858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2022] [Accepted: 03/02/2023] [Indexed: 03/19/2023] Open
Abstract
In this paper, the effect of Alcaligenes sp. on the corrosion process of X65 steel was investigated by using non-targeted metabolomics techniques for comprehensive characterization of metabolites, combined with surface analysis techniques and electrochemical testing. The results showed that the organic acids produced by Alcaligenes sp. accelerated the corrosion process of X65 steel in the early stage, and the presence of Alcaligenes sp. promoted the deposition of stable corrosion products and minerals in the middle and late stages. In addition, proteoglycans and corrosion inhibiting substances were enriched on the metal surface, which enhanced the stability of the film. The combined effect of multiple factors makes the mixed film of biofilm and corrosion products more dense and complete, which effectively inhibits the corrosion of X65 steel.
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Zhang W, Miao H, Liu J, Wu H, Wang Y, Gu P, Lei N, Yang K, Zheng Z, Li Q. Response of submerged macrophytes and biofilms to coexisting azithromycin and tetracycline: Antibiotic resistance genes removal, toxicity assessment and microbial properties. AQUATIC TOXICOLOGY (AMSTERDAM, NETHERLANDS) 2023; 256:106410. [PMID: 36724685 DOI: 10.1016/j.aquatox.2023.106410] [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: 07/12/2022] [Revised: 01/20/2023] [Accepted: 01/24/2023] [Indexed: 06/18/2023]
Abstract
Antibiotics, such as azithromycin (AZ), tetracycline (TC), and their related antibiotic resistance genes (ARGs), create serious ecological risks to aquatic organisms. This study examined the response mechanisms of submerged macrophytes and periphytic biofilms to a mixture of AZ and TC pollution and determined the antibiotic removal efficiencies and fate of ARGs. The results showed that the plant-biofilm system had a significant capacity for removing both single and combined antibiotics with removal efficiencies of 93.06% ∼99.80% for AZ and 73.35% ∼97.74% for TC. Higher ARG (tetA, tetC, tetW, ermF, ermX, and ermB) abundances were observed in the biofilm, and subsequent exposure to the antibiotic mixture increased the abundances of these genes. Both single and combined antibiotics triggered antioxidant stress, but antagonistic effects were induced only with mixed AZ and TC exposure. Furthermore, the antibiotics changed the structural characteristics of extracellular polysaccharides and induced alterations in the structure of the biofilm microbial community. Increased N-acylated-l-homoserine lactone confirmed alternations in microbial quorum-sensing. The results extend the understanding of the fate of antibiotics and ARGs when aquatic plants and biofilms are exposed to antibiotic mixtures, as well as the organism's response mechanisms.
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Affiliation(s)
- Weizhen Zhang
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Hengfeng Miao
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Jing Liu
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Hanqi Wu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Yuting Wang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Peng Gu
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Ningfei Lei
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China
| | - Kunlun Yang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, PR China
| | - Zheng Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Qi Li
- College of Ecology and Environment, Chengdu University of Technology, Chengdu 610059, PR China; State Key Laboratory of Geohazard Prevention and Geoenviroment Protection, Chengdu University of Technology, Chengdu 610059, PR China.
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Shen Y, Yu F, Qiu L, Gao M, Xu P, Zhang L, Liao X, Wang M, Hu X, Sun Y, Pan Y. Ecological influence by colonization of fluoride-resistant Streptococcus mutans in oral biofilm. Front Cell Infect Microbiol 2023; 12:1106392. [PMID: 36699726 PMCID: PMC9868560 DOI: 10.3389/fcimb.2022.1106392] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2022] [Accepted: 12/14/2022] [Indexed: 01/10/2023] Open
Abstract
Background Dental caries is one of the oldest and most common infections in humans. Improved oral hygiene practices and the presence of fluoride in dentifrices and mouth rinses have greatly reduced the prevalence of dental caries. However, increased fluoride resistance in microbial communities is concerning. Here, we studied the effect of fluoride-resistant Streptococcus mutans (S. mutans) on oral microbial ecology and compare it with wild-type S. mutans in vitro. Methods Biofilm was evaluated for its polysaccharide content, scanning electron microscopy (SEM) imaging, acid-producing ability, and related lactic dehydrogenase (LDH), arginine deiminase (ADS), and urease enzymatic activity determination. Fluorescence in situ hybridization (FISH) and quantitative real-time polymerase chain reaction (qRT-PCR) were used to evaluate the S. mutans ratio within the biofilm. It was followed by 16S rRNA sequencing to define the oral microbial community. Results Fluoride-resistant S. mutans produced increased polysaccharides in presence of NaF (P < 0.05). The enzymatic activities related to both acid and base generation were less affected by the fluoride. In presence of 275 ppm NaF, the pH in the fluoride-resistant strain sample was lower than the wild type. We observed that with the biofilm development and accumulative fluoride concentration, the fluoride-resistant strain had positive relationships with other bacteria within the oral microbial community, which enhanced its colonization and survival. Compared to the wild type, fluoride-resistant strain significantly increased the diversity and difference of oral microbial community at the initial stage of biofilm formation (4 and 24 h) and at a low fluoride environment (0 and 275 ppm NaF) (P < 0.05). Kyoto Encyclopedia of Genes and Genomes (KEGG) analysis revealed that fluoride-resistant strain enhanced the metabolic pathways and glucose transfer. Conclusions Fluoride-resistant S. mutans affected the microecological balance of oral biofilm and its cariogenic properties in vitro, indicating its negative impact on fluoride's caries prevention effect.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | - Yan Sun
- *Correspondence: Yihuai Pan, ; Yan Sun,
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Zhang H, Ge Z, Li Y, Huang S, Zhang J, Zheng Z. Response of submerged macrophytes and leaf biofilms to different concentrations of oxytetracycline and sulfadiazine. CHEMOSPHERE 2022; 308:136098. [PMID: 35995188 DOI: 10.1016/j.chemosphere.2022.136098] [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: 03/10/2022] [Revised: 07/09/2022] [Accepted: 08/15/2022] [Indexed: 06/15/2023]
Abstract
Oxytetracycline and sulfadiazine were widely used and they entered the environment through various channels such as domestic sewage, medical wastewater and agricultural wastewater, causing significant ecological risk. To determine the effects of different antibiotic concentrations on submerged macrophytes, Vallisneria natans was exposed to solutions containing different concentrations of oxytetracycline and sulfadiazine (0.1 mg/L、1 mg/L、10 mg/L、50 mg/L). After 20-days exposure, we found that 10 mg/L groups had a significant effect on Vallisneria natans. Under high antibiotic concentrations, the growth of Vallisneria natans was inhibited, chloroplasts were deformed, the chlorophyll content was reduced, and antioxidant enzyme activities, such as superoxide dismutase and glutathione, were increased. There was no significant difference between the control group and groups with low antibiotic concentrations (≤1 mg/L). The N-acyl-l-homoserine lactone concentration tended to increase with increasing antibiotic concentrations. The presence of antibiotics also affected the microbial community structure of biofilms on the submerged macrophytes. For example, the higher the concentration of antibiotics, the higher the proportion of Proteobacteria. These results suggest that high concentrations of oxytetracycline and sulfadiazine can disrupt homeostasis, induce effective Vallisneria natans defense mechanisms and alter biofilms in aquatic ecosystems.
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Affiliation(s)
- Hao Zhang
- Shanghai Shifang Ecology and Landscape Co., Ltd, Shanghai 200233, PR China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Zuhan Ge
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Yaguang Li
- Shanghai Shifang Ecology and Landscape Co., Ltd, Shanghai 200233, PR China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Suzhen Huang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Jibiao Zhang
- Shanghai Shifang Ecology and Landscape Co., Ltd, Shanghai 200233, PR China; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
| | - Zheng Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
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Yang YR, Wang XD, Chang JS, Lee DJ. Homogeneously and heterogeneously structured biofilm models for wastewater treatment. BIORESOURCE TECHNOLOGY 2022; 362:127763. [PMID: 35964918 DOI: 10.1016/j.biortech.2022.127763] [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: 07/26/2022] [Revised: 08/04/2022] [Accepted: 08/06/2022] [Indexed: 06/15/2023]
Abstract
Biofilm, a layer comprising extracellular polymeric substances, is the platform where the embedded living cells degrade the substances in the wastewaters. Biofilm models have been developed as part of the comprehensive models for the wastewater treatment process. This review summarizes the biofilm models applied in contemporary literature based on the spatial dimensions adopted for model build-up. The most commonly applied biofilm models are null-dimensional, considering the biofilm active biomass for the substrate sink's biological reaction. The one-dimensional, multi-species models are the second standard models for contemporary studies, providing transport and reaction resistances of substrates in the biofilm matrix and the interactions of competing or collaborating strains in the biofilm. The structural homogeneity of the biofilm challenges the validity of the uniformly structured models, highlighting the need to re-examine the validity of the uniformly structured models. The challenges and prospects of biofilm model developments and applications are outlined.
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Affiliation(s)
- Yan-Ru Yang
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Xiao-Dong Wang
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Jo-Shu Chang
- Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan; Department of Chemical Engineering, National Cheng Kung University, Tainan, Taiwan; Department of Chemical and Materials Engineering, Tunghai University, Taichung 407, Taiwan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong; Department of Chemical Engineering & Materials Science, Yuan Ze University, Chung-Li, 32003, Taiwan.
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Chen Y, Geng N, Hu T, Baeyens J, Wang S, Su H. Adaptive regulation of activated sludge's core functional flora based on granular internal spatial microenvironment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115714. [PMID: 35839647 DOI: 10.1016/j.jenvman.2022.115714] [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: 06/05/2022] [Revised: 07/04/2022] [Accepted: 07/07/2022] [Indexed: 06/15/2023]
Abstract
A great deal of efforts has been put into studying the influence of the external macroenvironment for activated sludge to survive on microbial community succession, while granular internal spatial microenvironment should be given equal attention, because it is more directly involved in the information exchange and material transfer among microorganisms. This study systematically investigated the effects of granular microenvironment on spatial colonization and composition of sludge's core functional flora, and the corresponding difference of biological treatment performance. High content of extracellular-proteins (67.53 mg/gVSS) or extracellular-polysaccharide (65.02 mg/gVSS) stimulated the microbial flocculation and aggregation of 0.5-1.5 mm granules (GS) or 1.5-3.0 mm granules (GM), respectively, which was resulted from excellent cell hydrophobicity (59.26%) or viscosity (3.47 mPa s), therefore, constituted relatively dense porous frame. More hollow space existed in 3.0-5.0 mm granules (GL), which formed loose skeleton with 0.213 mL/g of total pore volume and 17.21 nm of average pore size. Combining scanning electron microscope images and fluorescent in-situ hybridization based microbiological analysis, aerobic nitrifiers were observed to wrap or surround anaerobic bacteria, or facultative/anaerobic bacteria were self-encapsulated, which created granule's unique microenvironment with alternating aerobic and anaerobic zones. GS has the most rich organic matter degrading bacteria and anaerobic heterotrophic denitrifiers, while GM and GL presented the greatest relative abundance of facultative and aerobic denitrifiers, respectively. The activity of dehydrogenase and nitrogen invertase of GM showed be 1.32-3.09 times higher than those of GS and GL, contributing to its higher carbon and nitrogen removal. These findings highlight the importance of granular microenvironment to adaptive regulation of activated sludge's core functional flora and corresponding pollutant removal performance.
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Affiliation(s)
- Yingyun Chen
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Nanfei Geng
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Tenghui Hu
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Jan Baeyens
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China
| | - Shaojie Wang
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
| | - Haijia Su
- State Key Laboratory of Chemical Resource Engineering, Beijing Key Laboratory of Bioprocess, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, 100029, People's Republic of China.
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Chen L, Wang XD, Chang JS, Lee DJ. Biofilm with highly heterogeneous interior structure for pollutant removal: Effects of individual extracellular polymeric substance. BIORESOURCE TECHNOLOGY 2022; 361:127669. [PMID: 35878769 DOI: 10.1016/j.biortech.2022.127669] [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: 06/14/2022] [Revised: 07/16/2022] [Accepted: 07/18/2022] [Indexed: 06/15/2023]
Abstract
For the first time, this study reveals the effects of an individual component of extracellular polymeric substances on the substrate consumption rates by the embedded cells based on the highly heterogeneous interior structures of a working biofilm. The flow-across mode in operation established a boundary-layer flow field with high transport resistance, making the uniformly structured model valid. Conversely, the flow field of the flow-through mode is determined by 46% jointly by proteins and β-d-glucopyranose polysaccharides. The substrate consumption rates hindered by β-d-glucopyranose polysaccharide is up to 60% over the 20%-40% biofilm height from the bottom, much lower than expected by the uniformly structured models. The strategies to maximize the biofilm performance have been suggested.
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Affiliation(s)
- Liuyi Chen
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Xiao-Dong Wang
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Jo-Shu Chang
- Research Center for Smart Sustainable Circular Economy, Tunghai University, Taichung 407, Taiwan
| | - Duu-Jong Lee
- Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tong, Hong Kong; Department of Chemical Engineering & Materials Science, Yuan Ze University, Chung-Li 32003, Taiwan.
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Huang Q, Liu H, Zhang J, Wang S, Liu F, Li C, Wang G. Production of extracellular amylase contributes to the colonization of Bacillus cereus 0-9 in wheat roots. BMC Microbiol 2022; 22:205. [PMID: 35996113 PMCID: PMC9394064 DOI: 10.1186/s12866-022-02618-7] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/21/2022] [Accepted: 08/17/2022] [Indexed: 11/26/2022] Open
Abstract
Background Bacteria usually secrete a variety of extracellular enzymes to degrade extracellular macromolecules to meet their nutritional needs and enhance their environmental adaptability. Bacillus cereus 0–9, a biocontrol bacterial strain isolated from wheat roots, has three genes annotated as encoding amylases in the genome, but their functions are unknown, and whether they are involved in the colonization process of the bacterium remains to be further studied. Methods Mutant gene strains and fluorescently tagged strains were constructed by homologous recombination, and amylase protein was expressed in the prokaryotic Escherichia coli BL21(DE3) expression system. The iodine staining method was used to measure the activity of amylase proteins. We further observed the colonization abilities of the test strains in wheat roots through frozen section technology. Results The results showed that there were three amylase-encoding genes, amyC, amyP and amyS, in the B. cereus 0–9 genome. Among the three amylase encoding genes, only amyS produced extracellular amylase whose secretion was related to signal peptide at position 1–27. The AmyS protein encoded by the amyS gene is an α-amylase. The growth of Rhizoctonia cerealis was inhibited 84.7% by B. cereus 0–9, but the biocontrol ability of the ΔamyS strain decreased to 43.8% and that of ΔamyS/amyS was restored when the amyS gene was complemented. Furthermore, the biocontrol ability of the ΔamySec strain was decreased to 46.8%, almost the same as that of the ΔamyS mutant. Due to the deletion of the amyS gene, the colonization capacities of ΔamyS (RFP) and ΔamySec (RFP) in wheat roots decreased, while that of ΔamyS/amyS (RFP) was restored after the amyS gene was complemented, indicating that the amyS gene influences the colonization of B. cereus 0–9 in wheat roots. In addition, the colonization and biocontrol abilities of the mutant were restored after the addition of sugars, such as glucose and maltose. Conclusions B. cereus 0–9 encodes three genes annotated as amylases, amyC, amyP and amyS. Only the deletion of the amyS gene with a signal peptide did not produce extracellular amylase. The AmyS protein encoded by the amyS gene is an α-amylase. Our results indicated that the amyS gene is closely related to the colonization abilities of B. cereus 0–9 in wheat roots and the biocontrol abilities of B. cereus 0–9 to fight against R. cerealis. The extracellular amylase produced by B. cereus 0–9 can hydrolyze starch and use glucose, maltose and other nutrients to meet the needs of bacterial growth. Therefore, it is very possible that the secretion and hydrolytic activities of extracellular amylase can promote the colonization of B. cereus 0–9 in wheat roots and play important roles in the prevention and control of plant diseases. Our results contribute to exploring the mechanisms of microbial colonization in plant roots. Supplementary Information The online version contains supplementary material available at 10.1186/s12866-022-02618-7.
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Affiliation(s)
- Qiubin Huang
- Institute of Microbial Engineering, Henan University, Kaifeng, Henan, 475004, People's Republic of China.,School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Huiping Liu
- School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Juanmei Zhang
- Institute of Microbial Engineering, Henan University, Kaifeng, Henan, 475004, People's Republic of China.,Pharmaceutical College, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Shaowei Wang
- Institute of Microbial Engineering, Henan University, Kaifeng, Henan, 475004, People's Republic of China.,School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Fengying Liu
- Institute of Microbial Engineering, Henan University, Kaifeng, Henan, 475004, People's Republic of China.,School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Chengdie Li
- School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China
| | - Gang Wang
- Institute of Microbial Engineering, Henan University, Kaifeng, Henan, 475004, People's Republic of China. .,School of Life Sciences, Henan University, Kaifeng, Henan, 475004, People's Republic of China.
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13
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Zhang J, Huang D, Deng H, Zhang J. Responses of submerged plant Vallisneria natans growth and leaf biofilms to water contaminated with microplastics. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 818:151750. [PMID: 34808184 DOI: 10.1016/j.scitotenv.2021.151750] [Citation(s) in RCA: 26] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 11/11/2021] [Accepted: 11/13/2021] [Indexed: 06/13/2023]
Abstract
Microplastics pose a serious threat to ecological processes and environmental health. To evaluate the toxic effects of the exposure of microplastics on submerged plants and biofilms, eel grass (Vallisneria natans) was exposed to different concentrations of microplastics (10-50 mg L-1). The changes in microbial community on leaf biofilms were also tested. The results showed that the ratio of variable fluorescence to maximum fluorescence was largely unchanged, but the contents of chlorophyll a and b increased by 56.5% and 23.0% respectively. Different concentrations of exposure to microplastics effectively induced antioxidant responses, such as increasing the activities of superoxide dismutase, peroxidase and catalase, as well as increasing the activity of glutathione S-transferase and the contents of glutathione and malondialdehyde. In addition, the leaf flesh cells of Vallisneria natans showed some degree of organelle damage when examined by transmission electron microscopy. Moreover, a high-throughput sequencing analysis showed that the abundances and structure of the microbial community on the leaf biofilms were altered by exposure to microplastics. These results demonstrated that environmentally relevant concentrations of microplastics could disrupt homeostasis, induce effective defense mechanisms of Vallisneria natans and alter the biofilms in aquatic ecosystems.
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Affiliation(s)
- Jiawei Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Deying Huang
- Department of Chemistry, Fudan University, Shanghai 200433, PR China
| | - Hong Deng
- School of Ecological and Environmental Science, East China Normal University, Shanghai Key Lab for Urban Ecological Processes and Eco-Restoration, Institute of Eco-Chongming, Shanghai 200241, PR China
| | - Jibiao Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
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14
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Chen L, Wang XD, Lee DJ. Biofilm with highly heterogeneous interior structure for pollutant removal: Cell distribution and manipulated mass transport. BIORESOURCE TECHNOLOGY 2022; 343:125913. [PMID: 34649060 DOI: 10.1016/j.biortech.2021.125913] [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: 08/07/2021] [Revised: 09/03/2021] [Accepted: 09/04/2021] [Indexed: 06/13/2023]
Abstract
Biofilm wastewater treatment had been applied in practice. Conventionally the biofilm was modeled as a uniform structure to simplify the analysis. This study for the first time established a three-dimensional biofilm model with distributions separating living cells, Extracellular polymeric substances (EPS) and pores, based on which the local fluid flow velocity and pollutant diffusion and reaction fluxes inside the biofilm were numerically evaluated. Both the uniform structured and previously proposed heterogeneous models had been confirmed to overestimate the performances of a biofilm for wastewater treatment. The survival strategies of living cells in biofilm were discussed. Besides exposing to fresh pollutants for maximizing pollutant uptake, the tendency to form small aggregates of cells for shortening diffusion length so furnishing the pollutant with reduced diffusional resistance to living cells was also for the first time noted. This communication advanced the knowledge to comprehend the detailed processes in biofilm.
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Affiliation(s)
- Liuyi Chen
- State Key Laboratory of Alternate Electrical Power Systems with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China; Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China
| | - Xiao-Dong Wang
- State Key Laboratory of Alternate Electrical Power Systems with Renewable Energy Sources, North China Electric Power University, Beijing 102206, China; Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Mechanical Engineering, City University of Hong Kong, Kowloon Tang, Hong Kong, China; College of Engineering, Tunghai University, Taichung 40704, Taiwan.
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15
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Wang S, Huang X, Liu L, Yan P, Chen Y, Fang F, Guo J. Insight into the role of exopolysaccharide in determining the structural stability of aerobic granular sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 298:113521. [PMID: 34392097 DOI: 10.1016/j.jenvman.2021.113521] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/13/2021] [Revised: 07/19/2021] [Accepted: 08/07/2021] [Indexed: 06/13/2023]
Abstract
Extracellular polymeric substances (EPS) have a critical contribution to the stability of aerobic granular sludge (AGS), but the mechanism and details of EPS composition and function are far from clear. This work investigated the contribution of exopolysaccharide (PS) to maintaining the structural stability of AGS. The results revealed that PS hydrolysis induced by α-amylase, dextranase and cellulase significantly decreased the granular stability, whereas a substantial content reduction of extracellular protein (PN) was also observed. It was also found that hydrolysis of PS led to a decrease of sludge hydrophobicity, granular gel mechanical strength by 14.09 %, 38.67 %, respectively, and an increase of surface free energy by 49.59 %, which is not conducive to granular stability. Through fluorescent staining, existence of large amounts of PS and PN conjugates in EPS matrix was verified. It was proposed that these conjugates with PS as skeleton (PS-PN) dominate granular stability by affecting hydrophobicity interactions and hydrogen bonds system, which are two important parameters to gel properties, constituting a crucial finding of this work. This study offers an supplementation of EPS system theory and granular stability mechanism.
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Affiliation(s)
- Shuai Wang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China; College of Environmental Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Xiaoxiao Huang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Lijuan Liu
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Peng Yan
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Youpeng Chen
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Fang Fang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China.
| | - Jinsong Guo
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
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16
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Yau HCL, Malekpour AK, Momin NG, Morales-García AL, Willats WGT, Lant NJ, Jones CY. Removal of eDNA from fabrics using a novel laundry DNase revealed using high-resolution imaging. Sci Rep 2021; 11:21542. [PMID: 34728780 PMCID: PMC8563969 DOI: 10.1038/s41598-021-98939-0] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Accepted: 09/07/2021] [Indexed: 11/09/2022] Open
Abstract
Washed textiles can remain malodorous and dingy due to the recalcitrance of soils. Recent work has found that 'invisible' soils such as microbial extracellular DNA (eDNA) play a key role in the adhesion of extracellular polymeric substances that form matrixes contributing to these undesirable characteristics. Here we report the application of an immunostaining method to illustrate the cleaning mechanism of a nuclease (DNase I) acting upon eDNA. Extending previous work that established a key role for eDNA in anchoring these soil matrixes, this work provides new insights into the presence and effective removal of eDNA deposited on fabrics using high-resolution in-situ imaging. Using a monoclonal antibody specific to Z-DNA, we showed that when fabrics are washed with DNase I, the incidence of microbial eDNA is reduced. As well as a quantitative reduction in microbial eDNA, the deep cleaning benefits of this enzyme are shown using confocal microscopy and imaging analysis of T-shirt fibers. To the best of our knowledge, this is the first time the use of a molecular probe has been leveraged for fabric and homecare-related R&D to visualize eDNA and evaluate its removal from textiles by a new-to-laundry DNase enzyme. The approaches described in the current work also have scope for re-application to identify further cleaning technology.
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Affiliation(s)
- Hamish C L Yau
- Procter and Gamble, Newcastle Innovation Centre, Whitley Road, Newcastle upon Tyne, NE12 9BZ, UK
| | - Adam K Malekpour
- Procter and Gamble, Newcastle Innovation Centre, Whitley Road, Newcastle upon Tyne, NE12 9BZ, UK
| | - Nazarmohammad G Momin
- Procter and Gamble, Newcastle Innovation Centre, Whitley Road, Newcastle upon Tyne, NE12 9BZ, UK
| | - Ana L Morales-García
- Procter and Gamble, Newcastle Innovation Centre, Whitley Road, Newcastle upon Tyne, NE12 9BZ, UK
| | - William G T Willats
- School of Natural and Environmental Sciences, Newcastle University, Devonshire Building, Newcastle upon Tyne, NE1 7RU, UK.
| | - Neil J Lant
- Procter and Gamble, Newcastle Innovation Centre, Whitley Road, Newcastle upon Tyne, NE12 9BZ, UK.
| | - Catherine Y Jones
- School of Natural and Environmental Sciences, Newcastle University, Devonshire Building, Newcastle upon Tyne, NE1 7RU, UK.
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17
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Dong Y, Sui M, Wang X, Zhang P, Jiang Y, Wu J. Responses of electroactive biofilms to chronic chlorine exposure: Insights from the composition and spatial structure of extracellular polymeric substances. Bioelectrochemistry 2021; 142:107894. [PMID: 34371350 PMCID: PMC8492042 DOI: 10.1016/j.bioelechem.2021.107894] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/09/2021] [Revised: 07/20/2021] [Accepted: 07/21/2021] [Indexed: 11/29/2022]
Abstract
Extensive amounts of chlorine disinfectants have been applied to wastewater system since the outbreak of coronavirus disease 2019 (COVID-19), which inevitably affects the pollutant degradation via interfering with electron transfer mediated by electroactive bacteria. Herein, the response of electroactive biofilm (EAB) to chronic chlorine exposure was investigated. Results showed the EAB formed without exposure (EAB-0) exhibited a 53% and 123% higher current output than that formed with 0.1 mg L−1 (EAB-0.1) and 0.5 mg L−1 (EAB-0.5) chlorine, respectively. The chronic chlorine exposure of EAB boosted the contents of extracellular polymeric substances (EPS) in EAB-0.1 and EAB-0.5 by over secretion of extracellular polysaccharides. The EAB-0.1 and EAB-0.5 also presented lower electron exchange capacities (EECs) of EPS, coincided with reduced relative abundance of Geobacter from 61% in EAB-0 to 52% in EAB-0.5. This study provided new insights into the application of engineered EAB for wastewater treatment in a disinfection environment.
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Affiliation(s)
- Yue Dong
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Mingrui Sui
- College of Water Conservancy and Hydropower Engineering, Hohai University, Nanjing 210098, China.
| | - Xin Wang
- MOE Key Laboratory of Pollution Processes and Environmental Criteria and Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin 300350, China
| | - Peng Zhang
- Faculty of Environmental Science and Engineering, Kunming University of Science and Technology, Kunming 650500, China
| | - Yiying Jiang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
| | - Jianyu Wu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing 210098, China
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18
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Miao L, Gao Y, Adyel TM, Huo Z, Liu Z, Wu J, Hou J. Effects of biofilm colonization on the sinking of microplastics in three freshwater environments. JOURNAL OF HAZARDOUS MATERIALS 2021; 413:125370. [PMID: 33609862 DOI: 10.1016/j.jhazmat.2021.125370] [Citation(s) in RCA: 62] [Impact Index Per Article: 20.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 02/03/2021] [Accepted: 02/06/2021] [Indexed: 05/21/2023]
Abstract
Microplastics (MPs) have frequently been detected in freshwater environments, and there is growing concern about their ecological effects, especially the influence of the "plastisphere" on the freshwater ecosystems. The colonization of microbes on MPs would significantly alter their transport behavior, i.e., buoyancy, in fresh water. In this research, we studied the effects of biofilm colonization on the sinking and floating of three MPs, i.e., polyethylene terephthalate (PET), polypropylene (PP), and polyvinyl chloride (PVC), after 44 days of incubation in three freshwater systems (the Niushoushan River, the Qinhuai River, and East Lake) in China. The results showed that the biofilms attached to the three MPs contained different biomass and chlorophyll-a levels were related to water environmental conditions and physicochemical properties of MPs, based on redundancy analysis. Generally, PET and PVC sinking, with density higher than water, tended to increase after biofilm formation. Thereafter, the settling velocity of biofouled PET and PVC squares became faster than that of the virgin ones. In summary, our study suggested that biofouling does affect the sinking of MPs in fresh water and consequently influences the transport behavior and the distribution characteristics of MPs in freshwater environments, and this issue deserves more scientific attention.
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Affiliation(s)
- Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, People's Republic of China
| | - Yuxuan Gao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, People's Republic of China
| | - Tanveer M Adyel
- Department of Civil Engineering, Monash University, 23 College Walk, Clayton, VIC 3800, Australia
| | - Zongli Huo
- Jiangsu Provincial Center for Disease Control and Prevention, No.172 Jiangsu Road, Nanjing 210009, Jiangsu, People's Republic of China
| | - Zhilin Liu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, People's Republic of China
| | - Jun Wu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, People's Republic of China
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes, Ministry of Education, College of Environment, Hohai University, Nanjing 210098, People's Republic of China.
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Li Q, Gu P, Luo X, Zhang H, Huang S, Zhang J, Zheng Z. Pilot-scale study on the effects of cyanobacterial blooms on Vallisneria natans and biofilms at different phosphorus concentrations. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 265:114996. [PMID: 32593921 DOI: 10.1016/j.envpol.2020.114996] [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: 03/07/2020] [Revised: 06/02/2020] [Accepted: 06/06/2020] [Indexed: 06/11/2023]
Abstract
Cyanobacterial blooms cause potential risk to submerged macrophytes and biofilms in eutrophic environments. This pilot-scale study investigated the growth, oxidative responses, and detoxification activity of aquatic plants in response to cyanobacterial blooms under different phosphorus concentrations. Variations of extracellular polymeric substances (EPSs) and microbial community composition were also assessed. Results showed that the biomass of Vallisneria natans increased with exposure to cyanobacterial blooms at higher phosphorous concentrations (P > 0.2 mg L-1). The amount of microcystin compounds (MC-LR) released into the water and the accumulation of MC-LR into both plant tissue and biofilms changed according to the phosphorus concentration. Furthermore, a certain degree of oxidative stress was induced in the plants, as evidenced by increased activity of superoxide dismutase, catalase, and peroxidase, as well as increased malondialdehyde concentrations; significant differences were also seen in acid phosphatase and glutathione S-transferase activities, as well as in glutathione concentrations. Together, these responses indicate potential mechanisms of MC-LR detoxification. Broader α-D-glucopyranose polysaccharides (PS) increased with increasing phosphorous and aggregated into clusters in biofilm EPS in response to the cyanobacterial blooms. In addition, alterations were seen in the abundance and structure of the microbial communities present in exposed biofilms. These results demonstrate that cyanobacterial blooms under different concentrations of phosphorus can induce differential responses, which can have a significant impact on aquatic ecosystems.
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Affiliation(s)
- Qi Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Peng Gu
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Xin Luo
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Hao Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Suzhen Huang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Jibiao Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China
| | - Zheng Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai, 200433, PR China.
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20
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Li Q, Gu P, Zhang H, Luo X, Zhang J, Zheng Z. Response of submerged macrophytes and leaf biofilms to the decline phase of Microcystis aeruginosa: Antioxidant response, ultrastructure, microbial properties, and potential mechanism. THE SCIENCE OF THE TOTAL ENVIRONMENT 2020; 699:134325. [PMID: 31678882 DOI: 10.1016/j.scitotenv.2019.134325] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2019] [Revised: 09/02/2019] [Accepted: 09/05/2019] [Indexed: 06/10/2023]
Abstract
Decaying cyanobacterial blooms carry a potential risk for submerged macrophyte and periphyton biofilms in aquatic environments. This study comprehensively studied the responses in growth, oxidative response, detoxification pathway, and ultrastructure characteristics of aquatic plants to Microcystis aeruginosa (M. aeruginosa) exudates and extracts released during the decline phase. Particular emphasis was placed on the variation of extracellular polymeric substances (EPS) and quorum-sensing signaling molecules. The results showed that superoxide dismutase, peroxidase, and glutathione S-transferase were significantly induced as antioxidant response, and the malondialdehyde content increased. Increased content of MC-LR (1.129 μg L-1) and NH4+-N (1.35 mg L-1) were found in the decline phase of M. aeruginosa, which played a vital role in the damage to submerged plants. In addition, a change in the amount of osmiophilic granules and a variation of organelles and membranes was observed. A broad distribution of α-d-glucopyranose polysaccharides was dominant and aggregated into clusters in biofilm EPS in response to exposure to decaying M. aeruginosa. Furthermore, exposure to exudates and extracts changed the abundance and structure of the microbial biofilm community. Increased contents of N-acylated-L-homoserine lactone signal molecule might result in a variation of biofilm EPS production in response to decaying M. aeruginosa. These results expand the understanding of how submerged macrophyte and periphyton biofilms respond to environmental stress caused by exudates and extracts of decaying M. aeruginosa.
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Affiliation(s)
- Qi Li
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Peng Gu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Hao Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Xin Luo
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China
| | - Jibiao Zhang
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
| | - Zheng Zheng
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, PR China.
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21
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Du X, Xu J, Mo Z, Luo Y, Su J, Nie J, Wang Z, Liu L, Liang H. The performance of gravity-driven membrane (GDM) filtration for roofing rainwater reuse: Implications of roofing rainwater energy and rainwater purification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 697:134187. [PMID: 32380628 DOI: 10.1016/j.scitotenv.2019.134187] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/25/2019] [Revised: 08/26/2019] [Accepted: 08/28/2019] [Indexed: 06/11/2023]
Abstract
Rainwater harvesting (RWH) coupled with gravity-driven membrane (GDM) filtration was used to simultaneously treat rainwater and recover energy. A pilot GDM could obtain a relatively stable level of permeate flux (~4.0 L/(m2·h)) under a set water head (ΔH = 0.4 m) over 140 days of operation. An increase water head (ΔH = 0.6 m) did not achieve a sharp increase in stabilized flux (~2.4 L/(m2·h)) over 20 days of operation until the end. It was found that GDM filtration could produce a permeate that was almost free of particles. However, only a small amount of organic matter and trace metals (i.e., Cr, Al, Fe, Cu, Al, Mn and Ca) were removed, as demonstrated by excitation-emission matrix (EEM) and energy dispersive spectrometry (EDS) analysis. Additionally, the bacterial abundance within the permeate ((8.45 ± 0.11) × 102 cells/mL) decreased compared to that within the GDM tank ((1.85 ± 0.14) × 105 cells/mL), revealing that the rejected bacteria might enhance biofilm formation. The presence of extracellular polymeric substances (EPS), adenosine triphosphate (ATP) and assimilable organic carbon (AOC) indicated a high level of microbial activity within the biofilm, which was also demonstrated by the porous cake layer morphology observed by scanning electron microscopy (SEM) and results from confocal laser scanning microscopy (CLSM) imaging of the biofilm. NH3-N was removed by Nitrospira within the biofilm, which was identified by microbial community analysis. Overall, this novel approach has the potential to improve municipal water availability and stormwater management practices.
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Affiliation(s)
- Xing Du
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China.
| | - Jiongji Xu
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Zhuoyu Mo
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Yunlong Luo
- UNESCO Centre for Membrane Science and Technology, School of Chemical Engineering, UNSW Sydney, Australia
| | - Junhao Su
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Jinxu Nie
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Zhihong Wang
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Lifan Liu
- School of Civil and Transportation Engineering, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Heng Liang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
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22
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Lee YJ, Lei Z. Microalgal-bacterial aggregates for wastewater treatment: A mini-review. ACTA ACUST UNITED AC 2019. [DOI: 10.1016/j.biteb.2019.100199] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/29/2022]
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23
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Li X, Wang X, Lee DJ, Yan WM. Highly heterogeneous interior structure of biofilm wastewater for enhanced pollutant removals. BIORESOURCE TECHNOLOGY 2019; 291:121919. [PMID: 31376667 DOI: 10.1016/j.biortech.2019.121919] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/26/2019] [Revised: 07/24/2019] [Accepted: 07/25/2019] [Indexed: 06/10/2023]
Abstract
Biofilm processes are widely used in wastewater treatment. The biofilm has highly heterogeneous interior structure, which can significantly affect the transport processes and the biological reactions over the biofilm. This study for the first time detailed the complicated velocity and concentration fields of substrate in a real biofilm structure. With a real biofilm interior being profiled and meshed to numerical solutions, the flow-through mode has significant distortion of inflow velocity fields and concentration distributions, which lead to enhanced biological reactions at regimes nearby major pores. Conversely, the crossflow mode depends weakly on the biofilm interior structure. The uniform biofilm model fails to describe the real biofilm processes. Future research needs based on real biofilm structures were discussed.
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Affiliation(s)
- Xianyang Li
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Xiaodong Wang
- Research Center of Engineering Thermophysics, North China Electric Power University, Beijing 102206, China; School of Energy Power and Mechanical Engineering, North China Electric Power University, Beijing 102206, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan; Department of Chemical Engineering, National Taiwan University of Science and Technology, National Taiwan University of Science and Technology, Taipei 10607, Taiwan; College of Engineering, Tunghai University, Taichung 40704, Taiwan
| | - Wei-Mon Yan
- Department of Energy and Refrigerating Air-Conditioning Engineering, National Taipei University of Technology, Taipei 10608, Taiwan
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24
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Ye J, Hua X, Zhao Q, Zhao W, Chu G, Zhang W, Yang R. Chain conformation and rheological properties of an acid-extracted polysaccharide from peanut sediment of aqueous extraction process. Carbohydr Polym 2019; 228:115410. [PMID: 31635751 DOI: 10.1016/j.carbpol.2019.115410] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2019] [Revised: 09/21/2019] [Accepted: 09/29/2019] [Indexed: 12/20/2022]
Abstract
A polysaccharide (PPS) in peanut sediment of aqueous extraction process was obtained at pH4.0, purified via anion-exchange chromatography. The composition, chain conformation and rheological properties were investigated. PPS mainly consisted of arabinose, galacturonic acid, xylose, and rhamnose. The intrinsic viscosity [η] was 0.71 dL/g in 0.1 M NaNO3 solution. The weight-average molar mass Mw and polydispersity index were 3.77 × 105 g/mol and 1.25, suggesting high homogeneity. The average radius of gyration (Rg), hydrodynamic radius (Rh), Rg/Rh ratio and conformation parameter v were 25.5, 18.2, 1.40 and 0.21, respectively, indicating compact coil chain conformation with branched structure. Molecular morphology revealed that PPS displayed chain shape comprised of spheres with a diameter range of 15-50 nm and apparent length of chains mainly ranged from 100 to 300 nm. The aggregation caused by molecular self-association enhanced with concentration increasing. Additionally, Newtonian behavior was observed at various concentrations. Increase in temperature effectively broke this behavior. 10.0 wt.% PPS possessed activation energy of 21.7 KJ/mol, was structured liquid and almost fitted Cox-Merz rule. These closely related with its conformation and molecular self-association behavior.
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Affiliation(s)
- Jianfen Ye
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Xiao Hua
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Qiyan Zhao
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Wei Zhao
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Guanhe Chu
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Wenbin Zhang
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China
| | - Ruijin Yang
- State Key Laboratory of Food Science & Technology, School of Food Science and Technology, Jiangnan University, 214122, Wuxi, China.
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25
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Chang YR, Lee YJ, Lee DJ. Membrane fouling during water or wastewater treatments: Current research updated. J Taiwan Inst Chem Eng 2019. [DOI: 10.1016/j.jtice.2017.12.019] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/17/2022]
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26
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Cheng Y, Xuan X, Zhang L, Zhao J, Long B. Storage of aerobic granular sludge embedded in agar and its reactivation by real wastewater. JOURNAL OF WATER AND HEALTH 2018; 16:958-969. [PMID: 30540270 DOI: 10.2166/wh.2018.163] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Aerobic granular sludge (AGS) was preserved using an agar embedding method to maintain its stability. No obvious damage was imposed on the granular appearance during 30 days of cold and dry storage, but the granular microstructure had an uneven surface with a large number of holes. The results were consistent with the extinction of microbial communities and the monitored consumption of extracellular polymeric substances, in which granular specific oxygen utilization rate and mixed liquor volatile suspended solids/mixed liquor suspended solids ratio, respectively, decreased by 72.4% and 62.5% during storage. A mass conversation calculation indicated that the loss of granular mass was 1.6393 g. An offensive odour was smelled during storage, and the results indicated that a material transformation and mitigation were involved between AGS and the gas phase. Although the granular structure was destroyed to a certain extent, no obvious damage was imposed on the granular skeleton during storage. After it was aerated again after a feeding with real wastewater, the residual skeleton served as a carrier for the rapid proliferation of microorganisms, and good granular properties were obtained after 11 days of reactivation.
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Affiliation(s)
- Yuanyuan Cheng
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China E-mail:
| | - Xinpeng Xuan
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China E-mail:
| | - Linan Zhang
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China E-mail:
| | - Jue Zhao
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China E-mail:
| | - Bei Long
- School of Architectural and Surveying & Mapping Engineering, Jiangxi University of Science and Technology, Ganzhou 341000, Jiangxi, China E-mail:
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27
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You G, Wang P, Hou J, Wang C, Qian J, Ao Y, Chen J, Miao L, Xu Y, Feng T, Tao L. Investigation of the rheological behavior of activated sludge in response to CeO 2 nanoparticles and potential mechanism. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:29725-29733. [PMID: 30145757 DOI: 10.1007/s11356-018-2986-y] [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: 06/02/2018] [Accepted: 08/15/2018] [Indexed: 06/08/2023]
Abstract
With the rapid development of CeO2 nanoparticles (NPs), the released CeO2 NPs entering into wastewater treatment plants might bring the challenges for sludge pumping and mixing. In this study, we firstly elucidated the rheological behavior of 4.0 wt% sludge at various concentrations of CeO2 NPs. With the increase of CeO2 NPs to 5 mg/L, the shear stress at any given shear rate was reduced and the limiting viscosity was also decreased, indicating the sludge became more flowability. The dynamic sweep tests further demonstrated the decreased elastic behavior and weakened internal structure in response to low concentrations of CeO2 NPs (≤ 5 mg/L). However, 20 mg/L CeO2 NPs had negative effects on the rheological evolution of sludge, namely, better solid-like property and higher elastic structure. These results were mainly attributed to the combination of the decreased β-D-glucopyranose polysaccharides which support the rigid structure of sludge and the dramatically increased protein content (especially in 20 mg/L CeO2 NPs). These results can potentially provide novel information for the efficient design of sludge treatment when coped with CeO2 NPs. Graphical abstract ᅟ.
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Affiliation(s)
- Guoxiang You
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China.
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China.
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Jin Qian
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Yanhui Ao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Juan Chen
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Yi Xu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Tao Feng
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
| | - Li Tao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, China
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28
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Wang P, You G, Hou J, Wang C, Xu Y, Miao L, Feng T, Zhang F. Responses of wastewater biofilms to chronic CeO 2 nanoparticles exposure: Structural, physicochemical and microbial properties and potential mechanism. WATER RESEARCH 2018; 133:208-217. [PMID: 29407701 DOI: 10.1016/j.watres.2018.01.031] [Citation(s) in RCA: 50] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/12/2017] [Revised: 01/11/2018] [Accepted: 01/13/2018] [Indexed: 06/07/2023]
Abstract
With the accelerated application of CeO2 nanoparticles (NPs), wastewater treatment plants will increasingly receive CeO2 NPs, thus inevitably causing CeO2 NPs to encounter microaggregates. Here, we comprehensively elucidate the responses in the structural, physicochemical and microbial properties of wastewater biofilms to chronic exposure (75 days) to different CeO2 NPs concentrations, with a particular emphasis on the protective mechanisms of stratified extracellular polymeric substances (EPSs). Chronic exposure to 0.1 mg/L CeO2 NPs boosted the content and broadened the distribution of α-d-glucopyranose polysaccharides (PS), while the sharply increased production and breadth of β-d-glucopyranose PS, forming a formidable shield, was a response to 10 mg/L CeO2 NPs. After the bacteria were exposed to CeO2 NPs, loosely bound EPSs (LB-EPSs) aggregated into macromolecules (increasing in apparent molecular weight (AMW)) but at a lower abundance, whereas the average AMW in tightly bound EPSs (TB-EPSs) decreased. The acetyl content and (α-helix+3-turn helix)/β-sheet value of TB-EPSs increased to resist CeO2 NPs. Furthermore, long-term exposure to CeO2 NPs decreased cell viability, reduced microbial diversity and shifted the microbial composition. N-acylated-l-homoserine lactone concentrations increased with increased density of Pseudomonas, which was associated with PS-regulated control, thus promoting PS production in EPSs in response to CeO2 NPs. These results expand the understanding of how microaggregates resist environmental stress caused by NPs.
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Affiliation(s)
- Peifang Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Guoxiang You
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Jun Hou
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China.
| | - Chao Wang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Yi Xu
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Lingzhan Miao
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Tao Feng
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Fei Zhang
- Key Laboratory of Integrated Regulation and Resources Development on Shallow Lakes of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
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29
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Kong Z, Wang X, Liu Q, Li T, Chen X, Chai L, Liu D, Shen Q. Evolution of various fractions during the windrow composting of chicken manure with rice chaff. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2018; 207:366-377. [PMID: 29182981 DOI: 10.1016/j.jenvman.2017.11.023] [Citation(s) in RCA: 31] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2017] [Revised: 11/06/2017] [Accepted: 11/07/2017] [Indexed: 06/07/2023]
Abstract
Different fractions during the 85-day windrow composting were characterized based on various parameters, such as physiochemical properties and hydrolytic enzyme activities; several technologies were used, including spectral scanning techniques, confocal laser scanning microscopy (CLSM) and 13C Nuclear Magnetic Resonance Spectroscopy (13C NMR). The evaluated parameters fluctuated strongly during the first 3 weeks which was the most active period of the composting process. The principal components analysis (PCA) results showed that four classes of the samples were clearly distinguishable, in which the physiochemical parameters were similar, and that the dynamics of the composting process was significantly influenced by C/N and moisture content. The 13C NMR results indicated that O-alkyl-C was the predominant group both in the solid and water-soluble fractions (WSF), and the decomposition of O-alkyl-C mainly occurred during the active stage. In general, the various parameters indicated that windrow composting is a feasible treatment that can be used for the resource reuse of agricultural wastes.
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Affiliation(s)
- Zhijian Kong
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Xuanqing Wang
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Qiumei Liu
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Tuo Li
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Xing Chen
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Lifang Chai
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
| | - Dongyang Liu
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China.
| | - Qirong Shen
- Jiangsu Key Laboratory for Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, 210095, China; Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, China
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30
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Zhang Y, Shi C, Wang C, Lu Z, Wang F, Feng J, Wang Y. Effect of soybean meal fermented with Bacillus subtilis BS12 on growth performance and small intestinal immune status of piglets. FOOD AGR IMMUNOL 2017. [DOI: 10.1080/09540105.2017.1360258] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022] Open
Affiliation(s)
- Yu Zhang
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Changyou Shi
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Cheng Wang
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Zeqing Lu
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Fengqin Wang
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Jie Feng
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
| | - Yizhen Wang
- Key Laboratory of Animal Nutrition and Feed Science, Ministry of Agriculture (East China), Zhejiang Provincial Laboratory of Feed and Animal Nutrition, Institute of Feed Science, Zhejiang University, Hangzhou, People’s Republic of China
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31
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Wright KM, Crozier L, Marshall J, Merget B, Holmes A, Holden NJ. Differences in internalization and growth of Escherichia coli O157:H7 within the apoplast of edible plants, spinach and lettuce, compared with the model species Nicotiana benthamiana. Microb Biotechnol 2017; 10:555-569. [PMID: 28169510 PMCID: PMC5404196 DOI: 10.1111/1751-7915.12596] [Citation(s) in RCA: 46] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2016] [Accepted: 12/14/2016] [Indexed: 11/30/2022] Open
Abstract
Internalization of food-borne bacteria into edible parts of fresh produce plants represents a serious health risk. Therefore, internalization of verocytotoxigenic E. coli O157:H7 isolate Sakai was assessed in two species associated with outbreaks, spinach (Spinacia oleracea) and lettuce (Lactuca sativa) and compared to the model species Nicotiana benthamiana. Internalization occurred in the leaves and roots of spinach and lettuce throughout a 10 day time-course. The plant species, tissue type and inoculum dose all impacted the outcome. A combination of low inoculum dose (~102 CFU) together with light microscopy imaging highlighted marked differences in the fate of endophytic E. coli O157:H7 Sakai. In the fresh produce species, bacterial growth was restricted but viable cells persisted over 20 days, whereas there was > 400-fold (~2.5 Log10 ) increase in growth in N. benthamiana. Colony formation occurred adjacent to epidermal cells and mesophyll cells or close to vascular bundles of N. benthamiana and contained components of a biofilm matrix, including curli expression and elicitation, extracellular DNA and a limited presence of cellulose. Together the data show that internalization is a relevant issue in crop production and that crop species and tissue need to be considered as food safety risk parameters.
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Affiliation(s)
| | - Louise Crozier
- Cell and Molecular SciencesThe James Hutton InstituteDundeeUK
| | | | - Bernhard Merget
- Cell and Molecular SciencesThe James Hutton InstituteDundeeUK
| | - Ashleigh Holmes
- Cell and Molecular SciencesThe James Hutton InstituteDundeeUK
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32
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Huang L, Li X, Ren Y, Wang X. A monolithic three-dimensional macroporous graphene anode with low cost for high performance microbial fuel cells. RSC Adv 2016. [DOI: 10.1039/c5ra24718g] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Monolithic 3D-G which is inflexible and has a macroporous structure, crumpled matrix, good conductivity and low cost enhanced the electrogenesis of a MFC.
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Affiliation(s)
- Lihua Huang
- Laboratory of Environmental Biotechnology
- School of Environmental and Civil Engineering
- Jiangnan University
- Wuxi 214122
- PR China
| | - Xiufen Li
- Laboratory of Environmental Biotechnology
- School of Environmental and Civil Engineering
- Jiangnan University
- Wuxi 214122
- PR China
| | - Yueping Ren
- Laboratory of Environmental Biotechnology
- School of Environmental and Civil Engineering
- Jiangnan University
- Wuxi 214122
- PR China
| | - Xinhua Wang
- Laboratory of Environmental Biotechnology
- School of Environmental and Civil Engineering
- Jiangnan University
- Wuxi 214122
- PR China
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33
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Xie GJ, Liu BF, Wang RQ, Ding J, Ren HY, Zhou X, Ren NQ. Bioaggregate of photo-fermentative bacteria for enhancing continuous hydrogen production in a sequencing batch photobioreactor. Sci Rep 2015; 5:16174. [PMID: 26538350 PMCID: PMC4633638 DOI: 10.1038/srep16174] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/05/2015] [Accepted: 10/09/2015] [Indexed: 11/10/2022] Open
Abstract
Hydrogen recovery through solar-driven biomass conversion by photo-fermentative bacteria (PFB) has been regarded as a promising way for sustainable energy production. However, a considerable fraction of organic substrate was consumed for the growth of PFB as biocatalysts, furthermore, these PFB were continuously washed out from the photobioreactor in continuous operation because of their poor flocculation. In this work, PFB bioaggregate induced by L-cysteine was applied in a sequencing batch photobioreactor to enhance continuous hydrogen production and reduce biomass washout. The effects of the hydraulic retention time (HRT), influent concentration and light intensity on hydrogen production of the photobioreactor were investigated. The maximum hydrogen yield (3.35 mol H2/mol acetate) and production rate (1044 ml/l/d) were obtained at the HRT of 96 h, influent concentration of 3.84 g COD/l, and light intensity of 200 W/m2. With excellent settling ability, biomass accumulated in the photobioreactor and reached 2.15 g/l under the optimum conditions. Structural analysis of bioaggregate showed that bacterial cells were covered and tightly linked together by extracellular polymeric substances, and formed a stable structure. Therefore, PFB bioaggregate induced by L-cysteine is an efficient strategy to improve biomass retention capacity of the photobioreactor and enhance hydrogen recovery efficiency from organic wastes.
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Affiliation(s)
- Guo-Jun Xie
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.,Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Bing-Feng Liu
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Rui-Qing Wang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jie Ding
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Hong-Yu Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Xu Zhou
- Advanced Water Management Centre, The University of Queensland, QLD 4072, Australia
| | - Nan-Qi Ren
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China
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Whiteley CG, Lee DJ. Bacterial diguanylate cyclases: structure, function and mechanism in exopolysaccharide biofilm development. Biotechnol Adv 2014; 33:124-141. [PMID: 25499693 DOI: 10.1016/j.biotechadv.2014.11.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 11/24/2014] [Accepted: 11/24/2014] [Indexed: 10/24/2022]
Abstract
The ubiquitous bacterial cyclic di-guanosine monophosphate (c-di-GMP) emerges as an important messenger for the control of many bacterial cellular functions including virulence, motility, bioluminescence, cellulose biosynthesis, adhesion, secretion, community behaviour, biofilm formation and cell differentiation. The synthesis of this cyclic nucleotide arises from external stimuli on various signalling domains within the N-terminal region of a dimeric diguanylate cyclase. This initiates the condensation of two molecules of guanosine triphosphate juxtaposed to each other within the C-terminal region of the enzyme. The biofilm from pathogenic microbes is highly resistant to antimicrobial agents suggesting that diguanylate cyclase and its product - c-di-GMP - are key biomedical targets for the inhibition of biofilm development. Furthermore the formation and long-term stability of the aerobic granule, a superior biofilm for biological wastewater treatment, can be controlled by stimulation of c-di-GMP. Any modulation of the synthetic pathways for c-di-GMP is clearly advantageous in terms of medical, industrial and/or environmental bioremediation implications. This review discusses the structure and reaction of individual diguanylate cyclase enzymes with a focus on new directions in c-di-GMP research. Specific attention is made on the molecular mechanisms that control bacterial exopolysaccharide biofilm formation and aerobic granules.
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Affiliation(s)
- Chris G Whiteley
- Graduate Institute of Applied Science & Technology, National Taiwan University of Science and Technology, Taipei, Taiwan.
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei, Taiwan; Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan
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35
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Yang YC, Liu X, Wan C, Sun S, Lee DJ. Accelerated aerobic granulation using alternating feed loadings: alginate-like exopolysaccharides. BIORESOURCE TECHNOLOGY 2014; 171:360-366. [PMID: 25218208 DOI: 10.1016/j.biortech.2014.08.092] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 08/20/2014] [Accepted: 08/21/2014] [Indexed: 06/03/2023]
Abstract
Alginate-like exopolysaccharides (ALE) likely contribute markedly to strength of aerobic granules. This study cultivated aerobic granules from propionate wastewaters using strategies with different organic loading rates (OLRs) (4.4-17.4 kg/m(3)-d). When the OLR increased suddenly, the constituent cells (Pseudomonas, Clostridium, Thauera and Arthrobacter) were stimulated to secret extracellular cyclic diguanylate (c-di-GMP) and produced excess ALE, which formed a large quantity of sticky materials that served as the precursor of aerobic granules. Formation of excess ALE was the prerequisite for accelerated granulation. Conversely, this study observed no enrichment of poly guluronic acid blocks in ALE during granulation.
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Affiliation(s)
- Ya-Chun Yang
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Supu Sun
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan; Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
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Lv Y, Wan C, Lee DJ, Liu X, Tay JH. Microbial communities of aerobic granules: granulation mechanisms. BIORESOURCE TECHNOLOGY 2014; 169:344-351. [PMID: 25063977 DOI: 10.1016/j.biortech.2014.07.005] [Citation(s) in RCA: 104] [Impact Index Per Article: 10.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/10/2014] [Revised: 06/30/2014] [Accepted: 07/01/2014] [Indexed: 06/03/2023]
Abstract
Aerobic granulation is an advanced biological wastewater treatment technology. This study for the first time identified the microbial communities of sliced samples of mature granules by polymerase chain reaction (PCR) amplification and denaturing gradient gel electrophoresis (DGGE) technique and those of whole growing granules by high-throughput sequencing technique. The sliced sample study revealed that mature granules have a spherical core with anaerobic Rhodocyclaceae covered by an outer spherical shell with both aerobic and anaerobic strains. The growing granule study showed that the flocculated flocs were first transited to young granules with increased abundances of Flavobacteriaceae, Xanthomonadaceae, Rhodobacteraceae and Microbacteriaceae, then the abundances of anaerobic strains were increased owing to the formation of anaerobic core. Since the present granules were cultivated from flocculated flocs, the microbial community data suggested that granules were formed via a deterministic rather than via a random aggregation-disintegration mechanism.
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Affiliation(s)
- Yi Lv
- Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Duu-Jong Lee
- Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan; Department of Chemical Engineering, National Taiwan University, Taipei 106, Taiwan.
| | - Xiang Liu
- Department of Environmental Science and Engineering, Fudan University, 220 Handan Road, Shanghai 200433, China
| | - Joo-Hwa Tay
- Department of Civil Engineering, University of Calgary, Calgary, Canada
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Wan C, Wang L, Lee DJ, Zhang Q, Li J, Liu X. Fungi aerobic granules and use of Fe(III)-treated granules for biosorption of antimony(V). J Taiwan Inst Chem Eng 2014. [DOI: 10.1016/j.jtice.2014.06.019] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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Song W, Pan X, Mu S, Zhang D, Yang X, Lee DJ. Biosorption of Hg(II) onto goethite with extracellular polymeric substances. BIORESOURCE TECHNOLOGY 2014; 160:119-122. [PMID: 24405654 DOI: 10.1016/j.biortech.2013.12.052] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2013] [Revised: 12/10/2013] [Accepted: 12/12/2013] [Indexed: 06/03/2023]
Abstract
This study characterized the interactions of goethite, EPS from cyanobacterium Chroococcus sp. and Hg(II) using excitation emission matrix (EEM) spectra and adsorption isotherms. Three protein-like fluorescence peaks were noted to quench in the presence of Hg(II). The estimated conditional stability constant (logKa) and the binding constant (logKb) of the studied EPS-Hg(II) systems ranged 3.84-4.24 and 6.99-7.69, respectively. The proteins in EPS formed stable complex with Hg(II). The presence of proteins of Chroococcus sp. enhanced the adsorption capacity of Hg(II) on goethite; therefore, the goethite-EPS soil is a larger Hg(II) sink than goethite alone soil. Biosorption significantly affects the mobility of Hg(II) in goethite soils.
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Affiliation(s)
- Wenjuan Song
- Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Xiangliang Pan
- Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China.
| | - Shuyong Mu
- Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Daoyong Zhang
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan
| | - Xue Yang
- Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, China
| | - Duu-Jong Lee
- Department of Chemical Engineering, National Taiwan University, Taipei 10617, Taiwan.
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Wan C, Yang X, Lee DJ, Wang XY, Yang Q, Pan X. Aerobic granulation of aggregating consortium X9 isolated from aerobic granules and role of cyclic di-GMP. BIORESOURCE TECHNOLOGY 2013; 152:557-561. [PMID: 24326212 DOI: 10.1016/j.biortech.2013.11.052] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/16/2013] [Revised: 11/16/2013] [Accepted: 11/20/2013] [Indexed: 06/03/2023]
Abstract
This study monitored the granulation process of an aggregating functional consortium X9 that was consisted of Pseudomonas putida X-1, Acinetobacter sp. X-2, Alcaligenes sp. X-3 and Comamonas testosteroni X-4 in shaken reactors. The growth curve of X9 was fit using logistic model as follows y=1.49/(1+21.3*exp(-0.33x)), the maximum specific cell growth rate for X9 was 0.33 h(-1). Initially X9 consumed polysaccharides (PS) and secreted proteins (PN) to trigger granulation. Then X9 grew in biomass and formed numerous micro-granules, driven by increasing hydrophobicity of cell membranes and of accumulated extracellular polymeric substances (EPS). In later stage the intracellular cyclic diguanylate (c-di-GMP) was at high levels for inhibiting bacteria swarming motility, thereby promotion formation of large aerobic granules. The findings reported herein advise the way to accelerate granule formation and to stabilize operation in aerobic granular reactors.
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Affiliation(s)
- Chunli Wan
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China
| | - Xue Yang
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
| | - Duu-Jong Lee
- Department of Environmental Science and Engineering, Fudan University, Shanghai 200433, China; State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China; Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan.
| | - Xin-Yue Wang
- Department of Chemical Engineering, National Taiwan University of Science and Technology, Taipei 106, Taiwan
| | - Qiaoli Yang
- China Northeast Municipal Engineering Design and Research Institute, Changchun 130021, Jilin, China
| | - Xiangliang Pan
- State Key Laboratory of Desert and Oasis Ecology, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, Xinjiang, China
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Zeng QH, Zhang XW, Xu KP, Jiang JG. Application of fluorescently labeled tracer technique for detection of natural active macromolecules in Chinese medicine. Drug Metab Rev 2013; 46:57-71. [DOI: 10.3109/03602532.2013.839699] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
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41
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Cao W, Xu H, Zhang H. Architecture and functional groups of biofilms during composting with and without inoculation. Process Biochem 2013. [DOI: 10.1016/j.procbio.2013.06.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Liu BR, Huang YW, Lee HJ. Mechanistic studies of intracellular delivery of proteins by cell-penetrating peptides in cyanobacteria. BMC Microbiol 2013; 13:57. [PMID: 23497160 PMCID: PMC3637573 DOI: 10.1186/1471-2180-13-57] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2012] [Accepted: 03/08/2013] [Indexed: 11/10/2022] Open
Abstract
Background The plasma membrane plays an essential role in selective permeability, compartmentalization, osmotic balance, and cellular uptake. The characteristics and functions of cyanobacterial membranes have been extensively investigated in recent years. Cell-penetrating peptides (CPPs) are special nanocarriers that can overcome the plasma membrane barrier and enter cells directly, either alone or with associated cargoes. However, the cellular entry mechanisms of CPPs in cyanobacteria have not been studied. Results In the present study, we determine CPP-mediated transduction efficiency and internalization mechanisms in cyanobacteria using a combination of biological and biophysical methods. We demonstrate that both Synechocystis sp. PCC 6803 and Synechococcus elongatus PCC 7942 strains of cyanobacteria possess red autofluorescence. Green fluorescent protein (GFP), either alone or noncovalently associated with a CPP comprised of nine arginine residues (R9/GFP complexes), entered cyanobacteria. The ATP-depleting inhibitor of classical endocytosis, N-ethylmaleimide (NEM), could block the spontaneous internalization of GFP, but not the transduction of R9/GFP complexes. Three specific inhibitors of macropinocytosis, cytochalasin D (CytD), 5-(N-ethyl-N-isopropyl)-amiloride (EIPA), and wortmannin, reduced the efficiency of R9/GFP complex transduction, indicating that entry of R9/GFP complexes involves macropinocytosis. Both the 1-(4,5-dimethylthiazol-2-yl)-3,5-diphenylformazan (MTT) and membrane leakage analyses confirmed that R9/GFP complexes were not toxic to the cyanobacteria, nor were the endocytic and macropinocytic inhibitors used in these studies. Conclusions In summary, we have demonstrated that cyanobacteria use classical endocytosis and macropinocytosis to internalize exogenous GFP and CPP/GFP proteins, respectively. Moreover, the CPP-mediated delivery system is not toxic to cyanobacteria, and can be used to investigate biological processes at the cellular level in this species. These results suggest that both endocytic and macropinocytic pathways can be used for efficient internalization of regular protein and CPP-mediated protein delivery in cyanobacteria, respectively.
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Affiliation(s)
- Betty R Liu
- Department of Natural Resources and Environmental Studies, National Dong Hwa University, Hualien 97401, Taiwan
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Patterned hydrophobic domains in the exopolymer matrix of Shewanella oneidensis MR-1 biofilms. Appl Environ Microbiol 2012; 79:1400-2. [PMID: 23220957 DOI: 10.1128/aem.03054-12] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Water-dispersible amphiphilic surface-engineered quantum dots (QDs) were found to be strongly accumulated within discrete zones of the exopolymer network of Shewanella oneidensis MR-1 biofilms, but not on the cell surfaces. These microdomains showed a patterned distribution in the exopolymer matrix, which led to a restricted diffusion of the amphiphilic nanoparticles.
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Microbial relevant fouling in membrane bioreactors: influencing factors, characterization, and fouling control. MEMBRANES 2012; 2:565-84. [PMID: 24958297 PMCID: PMC4021913 DOI: 10.3390/membranes2030565] [Citation(s) in RCA: 43] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2012] [Revised: 07/20/2012] [Accepted: 08/09/2012] [Indexed: 11/17/2022]
Abstract
Microorganisms in membrane bioreactors (MBRs) play important roles on degradation of organic/inorganic substances in wastewaters, while microbial deposition/growth and microbial product accumulation on membranes potentially induce membrane fouling. Generally, there is a need to characterize membrane foulants and to determine their relations to the evolution of membrane fouling in order to identify a suitable fouling control approach in MBRs. This review summarized the factors in MBRs that influence microbial behaviors (community compositions, physical properties, and microbial products). The state-of-the-art techniques to characterize biofoulants in MBRs were reported. The strategies for controlling microbial relevant fouling were discussed and the future studies on membrane fouling mechanisms in MBRs were proposed.
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Zhang D, Lee DJ, Pan X. Fluorescent quenching for biofilm extracellular polymeric substances (EPS) bound with Cu(II). J Taiwan Inst Chem Eng 2012. [DOI: 10.1016/j.jtice.2011.12.010] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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Extracellular Polymeric Substances (EPS) from Aerobic Granular Sludges: Extraction, Fractionation, and Anionic Properties. Appl Biochem Biotechnol 2012; 166:1685-702. [DOI: 10.1007/s12010-012-9569-z] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/30/2011] [Accepted: 01/18/2012] [Indexed: 11/25/2022]
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Wu Y, Li T, Yang L. Mechanisms of removing pollutants from aqueous solutions by microorganisms and their aggregates: a review. BIORESOURCE TECHNOLOGY 2012; 107:10-8. [PMID: 22257855 DOI: 10.1016/j.biortech.2011.12.088] [Citation(s) in RCA: 110] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/24/2011] [Revised: 12/16/2011] [Accepted: 12/18/2011] [Indexed: 05/18/2023]
Abstract
With the public's enhanced awareness of eco-safety, environmentally benign measures based on microorganisms and microbial aggregates have become more accepted as methods of removing pollutants from aquatic systems. In this review, the application of microorganisms and microbial aggregates for removing pollutants from aqueous solutions is introduced and described based on mechanisms such as assimilation, adsorption, and biodegradation. The advantages of and future studies regarding the use of microorganisms and microbial aggregates to remove pollutants are discussed. Due to the limitation of a single microorganism species in adapting to heterogeneous conditions, this review demonstrates that the application of microbial aggregates consisting of multiple photoautotrophic and heterotrophic microorganisms, is a promising method of removing multiple pollutants from complex wastewaters and warrants further research.
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Affiliation(s)
- Yonghong Wu
- State Key Laboratory of Soil and Sustainable Agriculture, Institute of Soil Science, Chinese Academy of Sciences, No. 71, East Beijing Road, Nanjing 210008, PR China.
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Wang LP, Shen QR, Yu GH, Ran W, Xu YC. Fate of biopolymers during rapeseed meal and wheat bran composting as studied by two-dimensional correlation spectroscopy in combination with multiple fluorescence labeling techniques. BIORESOURCE TECHNOLOGY 2012; 105:88-94. [PMID: 22182472 DOI: 10.1016/j.biortech.2011.11.064] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Revised: 10/16/2011] [Accepted: 11/18/2011] [Indexed: 05/31/2023]
Abstract
Detailed knowledge of the molecular events during composting is important in improving the efficiency of this process. By combining two-dimensional Fourier transform infrared (FTIR) correlation spectroscopy and multiple fluorescent labeling, it was possible to study the degradation of biopolymers during rapeseed meal and wheat bran composting. Two-dimensional FTIR correlation spectroscopy provided structural information and was used to deconvolute overlapping bands found in the compost FTIR spectra. The degradation of biopolymers in rapeseed meal and wheat bran composts followed the sequence: cellulose, heteropolysaccharides, and proteins. Fluorescent labeling suggested that cellulose formed an intact network-like structure and the other biopolymers were embedded in the core of this structure. The sequence of degradation of biopolymers during composting was related to their distribution patterns.
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Affiliation(s)
- Li-Ping Wang
- Jiangsu Key Lab for Organic Solid Waste Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, PR China
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Experimental methods and modeling techniques for description of cell population heterogeneity. Biotechnol Adv 2011; 29:575-99. [DOI: 10.1016/j.biotechadv.2011.03.007] [Citation(s) in RCA: 91] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/11/2010] [Revised: 02/04/2011] [Accepted: 03/31/2011] [Indexed: 11/24/2022]
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Yu GH, Tang Z, Xu YC, Shen QR. Multiple fluorescence labeling and two dimensional FTIR-13C NMR heterospectral correlation spectroscopy to characterize extracellular polymeric substances in biofilms produced during composting. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2011; 45:9224-9231. [PMID: 21910500 DOI: 10.1021/es201483f] [Citation(s) in RCA: 25] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/31/2023]
Abstract
Knowledge on the structure and function of extracellular polymeric substances (EPS) in biofilms is essential for understanding biodegradation processes. Herein, a novel method based on multiple fluorescence labeling and two-dimensional (2D) FTIR-(13)C NMR heterospectral correlation spectroscopy was developed to gain insight on the composition, architecture, and function of EPS in biofilms during composting. Compared to other environmental biofilms, biofilms in the thermophilic (>55 °C) and cooling (mature) stage of composting have distinct characteristics. The results of multiple fluorescence labeling demonstrated that biofilms were distributed in clusters during the thermophilic stage (day 14), and dead cells were detected. In the mature stage (day 26), the biofilm formed a continuous layer with a thickness of approximately 20-100 μm around the compost, and recolonization of cells at the surface of the compost was easily observed. Through 2D FTIR-(13)C NMR correlation heterospectral spectroscopy, the following trend in the ease of the degradation of organic compounds was observed: heteropolysaccharides > cellulose > amide I in proteins. And proteins and cellulose showed significantly more degradation than heteropolysaccharides. In summary, the combination of multiple fluorescence labeling and 2D correlation spectroscopy is a promising approach for the characterization of EPS in biofilms.
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Affiliation(s)
- Guang-Hui Yu
- Jiangsu Key Lab for Organic Solid Waste Utilization, College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing 210095, People's Republic of China
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