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Yang T, Wang X, Jiang L, Sui X, Bi X, Jiang B, Zhang Z, Li X. Antibiotic resistance genes associated with size-segregated bioaerosols from wastewater treatment plants: A review. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123169. [PMID: 38128715 DOI: 10.1016/j.envpol.2023.123169] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2023] [Revised: 11/23/2023] [Accepted: 12/13/2023] [Indexed: 12/23/2023]
Abstract
The antibiotic-resistant pollution in size-segregated bioaerosols from wastewater treatment plants (WWTPs) is of increasing concern due to its public health risks, but an elaborate review is still lacking. This work overviewed the profile, mobility, pathogenic hosts, source, and risks of antibiotic resistance genes (ARGs) in size-segregated bioaerosols from WWTPs. The dominant ARG type in size-segregated bioaerosols from WWTPs was multidrug resistance genes. Treatment units that equipped with mechanical facilities and aeration devices, such as grilles, grit chambers, biochemical reaction tanks, and sludge treatment units, were the primary sources of bioaerosol antibiotic resistome in WWTPs. Higher enrichment of antibiotic resistome in particulate matter with an aerodynamic diameter of <2.5 μm, was found along the upwind-downwind-WWTPs gradient. Only a small portion of ARGs in inhalable bioaerosols from WWTPs were flanked by mobile genetic elements. The pathogens with multiple drug resistance had been found in size-segregated bioaerosols from WWTPs. Different ARGs or antibiotic resistant bacteria have different aerosolization potential associated with bioaerosols from various treatment processes. The validation of pathogenic antibiotic resistance bacteria, deeper investigation of ARG mobility, emission mechanism of antibiotic resistome, and development of treatment technologies, should be systematically considered in future.
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Affiliation(s)
- Tang Yang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Xuyi Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Lu Jiang
- College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao, 266100, PR China.
| | - Xin Sui
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Xuejun Bi
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Bo Jiang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Zhanpeng Zhang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Xinlong Li
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
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2
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Zhai Y, Tian W, Chen K, Lan L, Kan J, Shi H. Flagella-mediated adhesion of Escherichia coli O157:H7 to surface of stainless steel, glass and fresh produces during sublethal injury and recovery. Food Microbiol 2024; 117:104383. [PMID: 37918998 DOI: 10.1016/j.fm.2023.104383] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2023] [Revised: 09/06/2023] [Accepted: 09/10/2023] [Indexed: 11/04/2023]
Abstract
E. coli O157:H7 can be induced into sublethally injured (SI) state by lactic acid (LA) and regain activity in nutrient environments. This research clarified the role of flagella-related genes (fliD, fliS, cheA and motA) in adhesion of E. coli O157:H7 onto stainless steel, glass, lettuce, spinach, red cabbage and cucumber during LA-induced SI and recovery by plate counting. Results of adhesion showed improper flagellar rotation caused by the deletion of motA resulting in the decreased adhesion. Motility of wildtype determined by diameter of motility halo decreased in SI state and repaired with recovery time increasing, lagging behind changes in expression of flagella-related genes. Flagellar function-impaired strains all exhibited non-motile property. Thus, we speculated that flagella-mediated motility is critical in early stage of adhesion. We also found the effects of Fe2+, Ca2+ and Mn2+ on adhesion or motility of wildtype was independent of bacterial states. However, the addition of Ca2+ and Mn2+ did not affect motility of flagellar function-impaired strains as they did on wildtype. This research provides new insights to understand the role of flagella and cations in bacterial adhesion, which will aid in development of anti-adhesion agents to reduce bio-contamination in food processing.
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Affiliation(s)
- Yujun Zhai
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Weina Tian
- College of Bioengineering, Beijing Polytechnic, Beijing, 100176, China
| | - Kewei Chen
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Linshu Lan
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Jianquan Kan
- College of Food Science, Southwest University, Chongqing, 400715, China
| | - Hui Shi
- College of Food Science, Southwest University, Chongqing, 400715, China.
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3
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Abbas S, Yasmin A, Maqbool N, Shah AA, Fariq A. Insights into the microbiological and virulence characteristics of bacteria in orthopaedic implant infections: A study from Pakistan. PLoS One 2023; 18:e0292956. [PMID: 37847701 PMCID: PMC10581495 DOI: 10.1371/journal.pone.0292956] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/04/2023] [Accepted: 10/03/2023] [Indexed: 10/19/2023] Open
Abstract
The exponential increase in the prevalence of multidrug resistant bacteria has resulted in limiting surgical treatment options globally, potentially causing biofilm-related complications, implant failure, and severe consequences. This study aims to isolate and characterize bacteria from post-surgical orthopaedic implant infections and screening for multiple antibiotic resistance. A cross-sectional study was conducted, involving isolation of forty-four dominant pathogenic bacterial isolates from 16 infected implant samples from across Islamabad and Rawalpindi. Out of forty-four, 38% cocci and 61% bacilli were obtained. Approximately 90% of isolates showed multiple antibiotic resistance (MAR) index of more than 0.2. Eleven strains were identified via 16S rRNA gene sequencing as Pseudomonas aeruginosa, Bacillus spp., Planococcus chinensis, Staphylococcus, Escherichia coli and Enterobacter cloacae. The bacterial strain E. coli MB641 showed sensitivity to Polymyxin only, and was resistant to all other antibiotics used. Maximum biofilm forming ability 0.532 ± 0.06, 0.55 ± 0.01 and 0.557 ± 0.07 was observed in Pseudomonas aeruginosa MB663, Pseudomonas aeruginosa MB664 and Bacillus spp. MB647 respectively after 24 hours of incubation. EPS production of bacterial strains was assessed, the polysaccharides and protein content of EPS were found to be in the range of 11-32 μg/ml and 2-10 μg/ml, respectively. Fourier transform infrared spectroscopic analysis of EPS showed the presence of carbohydrates, proteins, alkyl halides, and nucleic acids. X-ray diffraction analysis revealed crystalline structure of EPS extracted from biofilm forming bacteria. These findings suggest a high prevalence of antibiotic-resistant bacteria in orthopaedic implant-associated surgeries, highlighting the urgent need for ongoing monitoring and microorganism testing in infected implants.
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Affiliation(s)
- Sidra Abbas
- Microbiology and Biotechnology Research laboratory, Department of Biotechnology, Fatima Jinnah Women University, Rawalpindi, Pakistan
| | - Azra Yasmin
- Microbiology and Biotechnology Research laboratory, Department of Biotechnology, Fatima Jinnah Women University, Rawalpindi, Pakistan
| | - Nouman Maqbool
- Department of Orthopaedic Surgery, Fauji Foundation Hospital, Rawalpindi, Pakistan
| | - Asim Ali Shah
- Microbiology Laboratory, Fauji Foundation Hospital, Rawalpindi, Pakistan
| | - Anila Fariq
- Microbiology and Biotechnology Research laboratory, Department of Biotechnology, Fatima Jinnah Women University, Rawalpindi, Pakistan
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Ghafouri M, Pourjafar F, Ghobadi Nejad Z, Yaghmaei S. Biological treatment of triclosan using a novel strain of Enterobacter cloacae and introducing naphthalene dioxygenase as an effective enzyme. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:131833. [PMID: 37473572 DOI: 10.1016/j.jhazmat.2023.131833] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/26/2023] [Revised: 05/22/2023] [Accepted: 06/09/2023] [Indexed: 07/22/2023]
Abstract
In recent years, triclosan (TCS) has been widely used as an antibacterial agent in personal care products due to the spread of the Coronavirus. TSC is an emerging contaminant, and due to its stability and toxicity, it cannot be completely degraded through traditional wastewater treatment methods. In this study, a novel strain of Enterobacter cloacae was isolated and identified that can grow in high TCS concentrations. Also, we introduced naphthalene dioxygenase as an effective enzyme in TCS biodegradation, and its role during the removal process was investigated along with the laccase enzyme. The change of cell surface hydrophobicity during TCS removal revealed that a glycolipid biosurfactant called rhamnolipid was involved in TCS removal, leading to enhanced biodegradation of TCS. The independent variables, such as initial TCS concentration, pH, removal duration, and temperature, were optimized using the response surface method (RSM). As a result, the maximum TCS removal (97%) was detected at a pH value of 7 and a temperature of 32 °C after 9 days and 12 h of treatment. Gas chromatography-mass spectrometry (GC/MS) analysis showed five intermediate products and a newly proposed pathway for TCS degradation. Finally, the phytotoxicity experiment conducted on Cucumis sativus and Lens culinaris seeds demonstrated an increase in germination power and growth of stems and roots in comparison to untreated water. These results indicate that the final treated water was less toxic.
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Affiliation(s)
- Mahsa Ghafouri
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
| | - Fatemeh Pourjafar
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran
| | - Zahra Ghobadi Nejad
- Biochemical & Bioenvironmental Research Center, Sharif University of Technology, Azadi Avenue, P.O Box 11155-1399, Tehran, Iran
| | - Soheila Yaghmaei
- Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran; Biochemical & Bioenvironmental Research Center, Sharif University of Technology, Azadi Avenue, P.O Box 11155-1399, Tehran, Iran.
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5
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Das S. Cell surface hydrophobicity and petroleum hydrocarbon degradation by biofilm-forming marine bacterium Pseudomonas furukawaii PPS-19 under different physicochemical stressors. JOURNAL OF HAZARDOUS MATERIALS 2023; 457:131795. [PMID: 37301070 DOI: 10.1016/j.jhazmat.2023.131795] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2023] [Revised: 05/19/2023] [Accepted: 06/05/2023] [Indexed: 06/12/2023]
Abstract
Biofilm-forming marine bacterium Pseudomonas furukawaii PPS-19 showed strong hydrophobicity under different physicochemical stressors, such as pH and salinity. Strong aggregation of P. furukawaii PPS-19 was observed at hydrophobic interfaces of n-dodecane and crude oil, while uptake of pyrene resulted in blue fluorescence of the bacterium. Changes in biofilm microcolonies were observed under different physicochemical stressors with maximum biofilm thickness of 15.15 µm and 15.77 µm at pH 7% and 1% salinity, respectively. Relative expression analysis of alkB2 gene revealed the maximum expression in n-dodecane (10.5 fold) at pH 7 (1 fold) and 1% salinity (8.3 fold). During the degradation process, a significant drop in surface tension resulted in increased emulsification activity. P. furukawaii PPS-19 showed the respective n-dodecane and pyrene degradation of 94.3% and 81.5% at pH 7% and 94.5% and 83% at 1% salinity. A significant positive correlation was obtained between cell surface hydrophobicity (CSH), biofilm formation, and PHs degradation (P < 0.05) under all the physicochemical stressors, with the highest value at pH 7% and 1% salinity. Analysis of metabolites indicated that mono-terminal oxidation and multiple pathways were followed for n-dodecane and pyrene biodegradation, respectively. Thus, P. furukawaii PPS-19 is an efficient hydrocarbonoclastic bacterium that may be exploited for large-scale oil pollution abatement.
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Affiliation(s)
- Surajit Das
- Laboratory of Environmental Microbiology and Ecology (LEnME), Department of Life Science, National Institute of Technology, Rourkela 769 008, Odisha, India.
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6
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Krohn C, Khudur L, Dias DA, van den Akker B, Rees CA, Crosbie ND, Surapaneni A, O'Carroll DM, Stuetz RM, Batstone DJ, Ball AS. The role of microbial ecology in improving the performance of anaerobic digestion of sewage sludge. Front Microbiol 2022; 13:1079136. [PMID: 36590430 PMCID: PMC9801413 DOI: 10.3389/fmicb.2022.1079136] [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: 10/25/2022] [Accepted: 11/28/2022] [Indexed: 12/15/2022] Open
Abstract
The use of next-generation diagnostic tools to optimise the anaerobic digestion of municipal sewage sludge has the potential to increase renewable natural gas recovery, improve the reuse of biosolid fertilisers and help operators expand circular economies globally. This review aims to provide perspectives on the role of microbial ecology in improving digester performance in wastewater treatment plants, highlighting that a systems biology approach is fundamental for monitoring mesophilic anaerobic sewage sludge in continuously stirred reactor tanks. We further highlight the potential applications arising from investigations into sludge ecology. The principal limitation for improvements in methane recoveries or in process stability of anaerobic digestion, especially after pre-treatment or during co-digestion, are ecological knowledge gaps related to the front-end metabolism (hydrolysis and fermentation). Operational problems such as stable biological foaming are a key problem, for which ecological markers are a suitable approach. However, no biomarkers exist yet to assist in monitoring and management of clade-specific foaming potentials along with other risks, such as pollutants and pathogens. Fundamental ecological principles apply to anaerobic digestion, which presents opportunities to predict and manipulate reactor functions. The path ahead for mapping ecological markers on process endpoints and risk factors of anaerobic digestion will involve numerical ecology, an expanding field that employs metrics derived from alpha, beta, phylogenetic, taxonomic, and functional diversity, as well as from phenotypes or life strategies derived from genetic potentials. In contrast to addressing operational issues (as noted above), which are effectively addressed by whole population or individual biomarkers, broad improvement and optimisation of function will require enhancement of hydrolysis and acidogenic processes. This will require a discovery-based approach, which will involve integrative research involving the proteome and metabolome. This will utilise, but overcome current limitations of DNA-centric approaches, and likely have broad application outside the specific field of anaerobic digestion.
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Affiliation(s)
- Christian Krohn
- ARC Training Centre for the Transformation of Australia's Biosolids Resource, RMIT University, Bundoora, VIC, Australia,*Correspondence: Christian Krohn,
| | - Leadin Khudur
- ARC Training Centre for the Transformation of Australia's Biosolids Resource, RMIT University, Bundoora, VIC, Australia
| | - Daniel Anthony Dias
- School of Health and Biomedical Sciences, Discipline of Laboratory Medicine, STEM College, RMIT University, Bundoora, VIC, Australia
| | | | | | | | - Aravind Surapaneni
- ARC Training Centre for the Transformation of Australia's Biosolids Resource, RMIT University, Bundoora, VIC, Australia
| | - Denis M. O'Carroll
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, Australia
| | - Richard M. Stuetz
- Water Research Centre, School of Civil and Environmental Engineering, University of New South Wales, Sydney, NSW, Australia
| | - Damien J. Batstone
- ARC Training Centre for the Transformation of Australia's Biosolids Resource, RMIT University, Bundoora, VIC, Australia,Australian Centre for Water and Environmental Biotechnology, Gehrmann Building, The University of Queensland, Brisbane, QLD, Australia
| | - Andrew S. Ball
- ARC Training Centre for the Transformation of Australia's Biosolids Resource, RMIT University, Bundoora, VIC, Australia
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7
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Shaffique S, Imran M, Wani SH, Khan MA, Kang SM, Adhikari A, Lee IJ. Evaluating the adhesive potential of the newly isolated bacterial strains in research exploitation of plant microbial interaction. FRONTIERS IN PLANT SCIENCE 2022; 13:1004331. [PMID: 36340407 PMCID: PMC9634002 DOI: 10.3389/fpls.2022.1004331] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2022] [Accepted: 10/06/2022] [Indexed: 05/26/2023]
Abstract
Bacterial adhesion potential constitutes the transition of bacteria from the planktonic to the static phase by promoting biofilm formation, which plays a significant role in plant-microbial interaction in the agriculture industry. In present study, the adhesion potential of five soil-borne bacterial strains belonging to different genera was studied. All bacterial strains were capable of forming colonies and biofilms of different levels of firmness on polystyrene. Significant variation was observed in hydrophobicity and motility assays. Among the five bacterial strains (SH-6, SH-8, SH-9, SH-10, and SH-19), SH-19 had a strong hydrophobic force, while SH-10 showed the most hydrophilic property. SH-6 showed great variability in motility; SH-8 had a swimming diffusion diameter of 70 mm, which was three times higher than that of SH-19. In the motility assay, SH-9 and SH-10 showed diffusion diameters of approximately 22 mm and 55 mm, respectively. Furthermore, among the five strains, four are predominately electron donors and one is electron acceptors. Overall, positive correlation was observed among Lewis acid base properties, hydrophobicity, and biofilm forming ability. However, no correlation of motility with bacterial adhesion could be found in present experimental work. Scanning electron microscopy images confirmed the adhesion potential and biofilm ability within extra polymeric substances. Research on the role of adhesion in biofilm formation of bacteria isolated from plants is potentially conducive for developing strategies such as plant-microbial interaction to mitigate the abiotic stress.
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Affiliation(s)
- Shifa Shaffique
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Muhammad Imran
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Shabir Hussain Wani
- Mountain Research for Field Crops Khudwani, Sher-e Kashmir University of Agricultural Sciences and Technology of Kashmir, Srinagar, Jamu and Kashmir, India
| | - Muhamad Aqil Khan
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Sang-Mo Kang
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - Arjun Adhikari
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
| | - In-Jung Lee
- Department of Applied Biosciences, Kyungpook National University, Daegu, South Korea
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8
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Yang T, Jiang L, Bi X, Cheng L, Zheng X, Wang X, Zhou X. Submicron aerosols share potential pathogens and antibiotic resistomes with wastewater or sludge. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 821:153521. [PMID: 35104511 DOI: 10.1016/j.scitotenv.2022.153521] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2021] [Revised: 01/24/2022] [Accepted: 01/25/2022] [Indexed: 06/14/2023]
Abstract
Generation of size-segregated aerosols is an important eco-environmental problem in wastewater treatment plants (WWTPs), but the characteristics of potential pathogens and antibiotic resistomes in submicron aerosols (PM1.0) were almost unknown. Here, 16S rRNA gene amplification and shotgun metagenome sequencing were respectively used to study the profiles of potential pathogens and antibiotic resistance genes (ARGs) in PM1.0 from a full-scale WWTP. Acinetobacter and sul1 were respectively the predominant potential pathogens and ARG subtypes in PM1.0 from aeration process. A total of 9 potential pathogens and 147 ARG subtypes, were shared among WWTP-PM1.0, wastewater/sludge, and ambient air. Significant differences of potential pathogens or ARGs were found between WWTP-PM1.0 and wastewater/sludge, however, wastewater/sludge had more crucial source contribution than the ambient air. Moreover, 13 potential pathogens and 40 ARG subtypes were easily aerosolized in PM1.0 from at least one of the treatment units. ARGs were mainly harbored by Proteobacteria, and multidrug resistance genes were the most ARG type carried by potential pathogens. Taken together, this study indicates the prevalence of potential pathogens, ARGs, and ARG-carrying potential pathogens in WWTP-PM1.0, which highlights the potential risk of PM1.0 in spreading potential pathogens and antibiotic resistomes into the air environments.
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Affiliation(s)
- Tang Yang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Lu Jiang
- College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, PR China.
| | - Xuejun Bi
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Lihua Cheng
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Xiang Zheng
- School of Environment & Natural Resources, Renmin University of China, Beijing 100872, PR China
| | - Xiaodong Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Xiaolin Zhou
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
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9
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Waheed H, Mehmood CT, Yang Y, Tan W, Fu S, Xiao Y. Dynamics of biofilms on different polymeric membranes – A comparative study using five physiologically and genetically distinct bacteria. J Memb Sci 2022. [DOI: 10.1016/j.memsci.2021.120000] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
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10
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Physicochemical and Functional Characterization of Newly Designed Biopolymeric-Based Encapsulates with Probiotic Culture and Charantin. Foods 2021; 10:foods10112677. [PMID: 34828958 PMCID: PMC8620448 DOI: 10.3390/foods10112677] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2021] [Revised: 10/26/2021] [Accepted: 10/27/2021] [Indexed: 01/02/2023] Open
Abstract
The identification of novel sources of synbiotic agents with desirable functionality is an emerging concept. In the present study, novel encapsulates containing probiotic L. acidophilus LA-05® (LA) and Charantin (CT) were produced by freeze-drying technique using pure Whey Protein Isolate (WPI), pure Maltodextrin (MD), and their combination (WPI + MD) in 1:1 core ratio, respectively. The obtained microparticles, namely WPI + LA + CT, MD + LA + CT, and WPI + MD + LA + CT were tested for their physicochemical properties. Among all formulations, combined carriers (WPI + MD) exhibited the highest encapsulation yields for LA (98%) and CT (75%). Microparticles showed a mean d (4, 3) ranging from 50.393 ± 1.26 to 68.412 ± 3.22 μm. The Scanning Electron Microscopy revealed uniformly amorphous and glass-like structures, with a noticeably reduced porosity when materials were combined. In addition, Fourier Transform Infrared spectroscopy highlighted the formation of strong hydrogen bonds supporting the interactions between the carrier materials (WPI and MD) and CT. In addition, the thermal stability of the combined WPI + MD was superior to that of pure WPI and pure MD, as depicted by the Thermogravimetric and Differential Scanning Calorimetry analysis. More interestingly, co-encapsulation with CT enhanced LA viability (8.91 ± 0.3 log CFU/g) and Cells Surface Hydrophobicity (82%) in vitro, in a prebiotic-like manner. Correspondingly, CT content was heightened when co-encapsulated with LA. Besides, WPI + MD + LA + CT microparticles exhibited higher antioxidant activity (79%), α-amylase inhibitory activity (83%), and lipase inhibitory activity (68%) than single carrier ones. Furthermore, LA viable count (7.95 ± 0.1 log CFU/g) and CT content (78%) were the highest in the blended carrier materials after 30 days of storage at 4 °C. Synbiotic microparticle WPI + MD + LA + CT represents an effective and promising approach for the co-delivery of probiotic culture and bioactive compounds in the digestive tract, with enhanced functionality and storage properties.
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Lotfikatouli S, Hadi P, Yang M, Walker HW, Hsiao BS, Gobler C, Reichel M, Mao X. Enhanced anti-fouling performance in Membrane Bioreactors using a novel cellulose nanofiber-coated membrane. Sep Purif Technol 2021. [DOI: 10.1016/j.seppur.2021.119145] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Yang T, Jiang L, Cheng L, Zheng X, Bi X, Wang X, Zhou X. Characteristics of size-segregated aerosols emitted from an aerobic moving bed biofilm reactor at a full-scale wastewater treatment plant. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125833. [PMID: 34492791 DOI: 10.1016/j.jhazmat.2021.125833] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/08/2020] [Revised: 03/21/2021] [Accepted: 04/04/2021] [Indexed: 06/13/2023]
Abstract
Aerosol emissions from wastewater treatment plants (WWTPs) have been associated with health reverberation but studies about characteristics of size-segregated aerosol particulate matter (PM) are scarce. In this study, the measurement of particulate number size distribution in the range of < 10 µm, and the collection of PM10-2.5, PM2.5-1.0 and PM1.0, were conducted from an aerobic moving bed biofilm reactor (MBBR) at a full-scale WWTP. MBBR aerosols showed a unimodal number size distribution, with the majority of particles (>94%) in the ultrafine size range (<100 nm). For toxic metal(loid)s or potential pathogens, significant differences were found within MBBR aerosols (PM10-2.5, PM2.5-1.0, and PM1.0), and also between MBBR aerosols and wastewater. Both wastewater and ambient air had important source contributions for MBBR aerosols. The compositions of toxic metal(loid)s in PM1.0, and the populations of potential bacterial or fungal pathogens in PM10-2.5 and PM2.5-1.0, were dominated by that from wastewater. Compared to PM10-2.5 and PM2.5-1.0, PM1.0 had the highest aerosolization potential for the toxic metal(loid)s of As, Cd, Co, Cr, Li, Mn, Ni, U, and Zn, and the genera of Acinetobacter, Pseudomonas and Fusarium. Due to the size-segregated specialty, targeted measures should be employed to reduce the health risks. CAPSULE: The compositions of toxic metal(loid)s in PM1.0, and the populations of potential pathogens in PM10-2.5 and PM2.5-1.0, were dominated by that from wastewater.
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Affiliation(s)
- Tang Yang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Lu Jiang
- College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao 266100, PR China.
| | - Lihua Cheng
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Xiang Zheng
- School of Environment & Natural Resources, Renmin University of China, Beijing 100872, PR China.
| | - Xuejun Bi
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Xiaodong Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Xiaolin Zhou
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
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13
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Yang T, Jiang L, Han Y, Liu J, Wang X, Yan X, Liu J. Linking aerosol characteristics of size distributions, core potential pathogens and toxic metal(loid)s to wastewater treatment process. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2020; 264:114741. [PMID: 32402711 DOI: 10.1016/j.envpol.2020.114741] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/17/2020] [Revised: 04/27/2020] [Accepted: 05/03/2020] [Indexed: 06/11/2023]
Abstract
Wastewater treatment plants (WWTPs) play important roles in water purification but are also important source of aerosols. However, the relationship between aerosol characteristics and wastewater treatment process remains poorly understood. In this study, aerosols were collected over a 24-month period from a WWTP using a modified anaerobic-anoxic-oxic process. The aerated tank (AerT) was characterized by the highest respiratory fraction (RF) concentrations (861-1525 CFU/m3) and proportions (50.76%-65.96%) of aerosol particles. Fourteen core potential pathogens and 15 toxic metal(loid)s were identified in aerosols. Mycobacterium was the genus that aerosolized most easily in fine grid, pre-anoxic tank, and AerT. High wastewater treatment efficiency may increase the emission of RF and core potential pathogens. The median size of activated sludge, richness of core potential pathogens in wastewater, and total suspended particulates were the most influential factors directly related to the RF proportions, core community of potential pathogens, and composition of toxic metal(loid)s in WWTP aerosols, respectively. Relative humidity, temperature, input and removal of biochemical oxygen demand, dissolved oxygen, and mixed liquor suspended solids could also directly or indirectly affect the aerosol characteristics. This study enhances the mechanistic understanding of linking aerosol characteristics to treatment processes and has important implications for targeted manipulation.
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Affiliation(s)
- Tang Yang
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 101408, PR China.
| | - Lu Jiang
- College of Oceanic and Atmospheric Sciences, Ocean University of China, Qingdao, 266100, PR China.
| | - Yunping Han
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 101408, PR China.
| | - Jianwei Liu
- School of Environment and Energy Engineering, Beijing University of Civil Engineering and Architecture, Beijing, 100044, PR China.
| | - Xiaodong Wang
- School of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao, 266033, PR China.
| | - Xu Yan
- School of Environment, Key Laboratory for Yellow River and Huai River Water Environment and Pollution Control, Ministry of Education, Henan Key Laboratory for Environmental Pollution Control, Henan Normal University, Xinxiang, Henan, 453007, PR China.
| | - Junxin Liu
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 100085, PR China; University of Chinese Academy of Sciences, Beijing, 101408, PR China.
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14
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Deng L, Guo W, Ngo HH, Wang XC, Hu Y, Chen R, Cheng D, Guo S, Cao Y. Application of a specific membrane fouling control enhancer in membrane bioreactor for real municipal wastewater treatment: Sludge characteristics and microbial community. BIORESOURCE TECHNOLOGY 2020; 312:123612. [PMID: 32526665 DOI: 10.1016/j.biortech.2020.123612] [Citation(s) in RCA: 22] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2020] [Revised: 05/28/2020] [Accepted: 05/29/2020] [Indexed: 06/11/2023]
Abstract
The feasibility of a novel bioflocculant (GemFloc™) for membrane fouling mitigation in membrane bioreactor (MBR) was investigated during real municipal wastewater treatment. When compared to the conventional MBR (CMBR), suspended sludge in the MBR with GemFloc™ (G-MBR) showed less soluble microbial products (SMP), higher ratios of proteins to polysaccharides in SMP (SMPP/SMPC) and loosely bound extracellular polymeric substances (LB-EPS). Adding GemFloc™ also enlarged floc size (> 200 µm), and increased tightly bound EPS levels, zeta potential and relative hydrophobicity of sludge flocs, further reduced cake layer and pore blocking resistances. Moreover, more diverse microbial community and enrichment of fouling reduction microbes such as Arenimonas and Flavihumibacter were observed in the G-MBR, together with less abundant microbes (e.g. Sphaerotilus and Povalibacter) which could aggravate membrane fouling. Therefore, GemFloc™ has high capability in improving sludge characteristics, mitigating membrane fouling and increasing diversity of special functional bacterial community in MBR.
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Affiliation(s)
- Lijuan Deng
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Wenshan Guo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia.
| | - Huu Hao Ngo
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, PR China
| | - Xiaochang C Wang
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, PR China
| | - Yisong Hu
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China; International Science & Technology Cooperation Center for Urban Alternative Water Resources Development, Xi'an 710055, PR China
| | - Rong Chen
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Dongle Cheng
- Centre for Technology in Water and Wastewater, School of Civil and Environmental Engineering, University of Technology Sydney, NSW 2007, Australia
| | - Shengquan Guo
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
| | - Yunyang Cao
- Key Lab of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, PR China
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15
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Elegbeleye J, Buys E. Molecular characterization and biofilm formation potential of Bacillus subtilis and Bacillus velezensis in extended shelf-life milk processing line. J Dairy Sci 2020; 103:4991-5002. [DOI: 10.3168/jds.2019-17919] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/16/2019] [Accepted: 02/12/2020] [Indexed: 12/15/2022]
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16
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Liu M, Nobu MK, Ren J, Jin X, Hong G, Yao H. Bacterial compositions in inhalable particulate matters from indoor and outdoor wastewater treatment processes. JOURNAL OF HAZARDOUS MATERIALS 2020; 385:121515. [PMID: 31718810 DOI: 10.1016/j.jhazmat.2019.121515] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 10/06/2019] [Accepted: 10/19/2019] [Indexed: 05/13/2023]
Abstract
Wastewater treatment systems are critical microbial sources for urban air and play important roles in public health. In this study, bacterial communities in particulate matters (PM2.5, PM10) from wastewater/sludge treatment facilities of two full-scale wastewater treatment plants were analyzed by 16S rRNA amplicon sequencing. Compared to the background ambient air, Campylobacteriadeceae, Aeromonadaceae, and Chlostridiaceae were the most enriched bacteria above wastewater treatment facilities. In sludge dewatering facilities, Comamonadaceae, Chitinophagaceae, Caldilineaceae, Mycobacteriaceae, Methylocystaceae, Microbacteriaceae, Cryomorphaceae, and uncultured Class OPB56 were the most enriched. The dynamic bacterial compositions in aerosols were contributed by aerosolization and dispersion. Principal coordinate analysis and clustering analysis showed that the aerosol bacterial community from indoor sludge treatment were closely clustered with that of sludge, indicating that aerosolization dominated the indoor environments. In contrast, aerosols from outdoor wastewater treatment facilities clustered with background ambient aerosols, indicating that outdoor aerosol bacterial communities were mainly governed by dispersion. Aerosolization factor (the ratio of bacteria abundance in aerosols to those in wastewater/sludge) was used to evaluate the aerosolization potential and survival of bacteria. Rhodocyclaceae, Arcobacter, Comamonadaceae, Mycobacterium, and Citrobacter were not only preferentially aerosolized from wastewater/sludge, but also sustainable during dispersion in ambient air.
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Affiliation(s)
- Miaomiao Liu
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, School of Civil Engineering, Beijing Jiaotong University, Beijing, China.; Department of Urban Engineering, The University of Tokyo, Tokyo, Japan
| | - Masaru K Nobu
- Bioproduction Research Institute, National Institute of Advanced Industrial Science and Technology, Tsukuba, Ibaraki, Japan
| | - Jia Ren
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, School of Civil Engineering, Beijing Jiaotong University, Beijing, China
| | - Xiaowei Jin
- China National Environmental Monitoring Center, Beijing, 100012, China
| | - Gang Hong
- Shijiazhuang Environmental Monitoring Station, Hebei Province, China
| | - Hong Yao
- Beijing International Scientific and Technological Cooperation Base of Water Pollution Control Techniques for Antibiotics and Resistance Genes, School of Civil Engineering, Beijing Jiaotong University, Beijing, China..
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17
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May HC, Yu JJ, Shrihari S, Seshu J, Klose KE, Cap AP, Chambers JP, Guentzel MN, Arulanandam BP. Thioredoxin Modulates Cell Surface Hydrophobicity in Acinetobacter baumannii. Front Microbiol 2019; 10:2849. [PMID: 31921031 PMCID: PMC6927278 DOI: 10.3389/fmicb.2019.02849] [Citation(s) in RCA: 16] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2019] [Accepted: 11/25/2019] [Indexed: 12/04/2022] Open
Abstract
Acinetobacter baumannii, a Gram-negative coccobacillus, has become a prevalent nosocomial health threat affecting the majority of hospitals both in the U.S. and around the globe. Microbial cell surface hydrophobicity (CSH) has previously been correlated with virulence, uptake by immune cells, and attachment to epithelial cells. A mutant strain of A. baumannii (ΔtrxA) lacking the redox protein thioredoxin A was found to be more hydrophobic than its wild type (WT) and complemented counterparts, as measured by both Microbial Adhesion to Hydrocarbon (MATH) and salt aggregation. The hydrophobicity of the mutant could be abrogated through treatment with sodium cyanoborohydride (SCBH). This modulation correlated with reduction of disulfide bonds, as SCBH was able to reduce 5,5′-dithio-bis-[2-nitrobenzoic acid] and treatment with the known disulfide reducer, β-mercaptoethanol, also decreased ΔtrxA CSH. Additionally, the ΔtrxA mutant was more readily taken up than WT by J774 macrophages and this differential uptake could be abrogated though SCBH treatment. When partitioned into aqueous and hydrophobic phases, ΔtrxA recovered from the hydrophobic partition was phagocytosed more readily than from the aqueous phase further supporting the contribution of CSH to A. baumannii uptake by phagocytes. A second Gram-negative bacterium, Francisella novicida, also showed the association of TrxA deficiency (FnΔtrxA) with increased hydrophobicity and uptake by J774 cells. We previously have demonstrated that modification of the type IV pilus system (T4P) was associated with the A. baumannii ΔtrxA phenotype, and the Francisella FnΔtrxA mutant also was found to have a marked T4P deficiency. Interestingly, a F. novicida mutant lacking pilT also showed increased hydrophobicity over FnWT. Collective evidence presented in this study suggests that Gram-negative bacterial thioredoxin mediates CSH through multiple mechanisms including disulfide-bond reduction and T4P modulation.
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Affiliation(s)
- Holly C May
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Jieh-Juen Yu
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Swathi Shrihari
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Janakiram Seshu
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Karl E Klose
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Andrew P Cap
- Acute Combat Casualty Care Research Division, U.S. Army Institute for of Surgical Research, JBSA-Fort Sam Houston, San Antonio, TX, United States
| | - James P Chambers
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - M Neal Guentzel
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
| | - Bernard P Arulanandam
- Department of Biology, South Texas Center for Emerging Infectious Diseases, University of Texas at San Antonio, San Antonio, TX, United States
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18
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Ku S, Ximenes E, Kreke T, Foster K, Couetil JL, Zuponcic J, Zhao X, Hoagland L, Deering AJ, Ladisch MR. Microbial enrichment and multiplexed microfiltration for accelerated detection of Salmonella in spinach. Biotechnol Prog 2019; 35:e2874. [PMID: 31228331 DOI: 10.1002/btpr.2874] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/11/2019] [Revised: 06/11/2019] [Accepted: 06/17/2019] [Indexed: 01/01/2023]
Abstract
To attain Salmonella detection thresholds in spinach suspensions using enrichment media requires at least 24 hr. Separation and concentration of selected microorganisms via microfiltration and microfugation reduce time for sample preparation, especially when working with large volumes of vegetable suspensions. This facilitates accelerated detection of Salmonella in spinach suspensions, and may contribute to effectively monitoring this pathogen before it reaches the consumer. We report a microfiltration-based protocol for accelerated sample preparation to concentrate and recover ≤1 colony forming unit (CFU) Salmonella/g pathogen-free spinach. Store-bought samples of spinach and a spinach plant subjected to two environmental conditions (temperature and light exposure) during its production were tested. The overall procedure involves extraction with buffer, a short enrichment step, prefiltration using a nylon filter, crossflow hollow fiber microfiltration, and retentate centrifugation to bring microbial cells to detection levels. Based on 1 CFU Salmonella/g frozen spinach, and a Poisson distribution statistical analyses with 99% probability, we calculated that 3 hr of incubation, when followed by microfiltration, is sufficient to reach the 2 log concentration required for Salmonella detection within 7 hr. Longer enrichment times (5 hr or more) is needed for concentrations lower than 1 CFU Salmonella/g of ready to eat spinach. The recovered microbial cells were identified and confirmed as Salmonella using both polymerase chain reaction (PCR) and plating methods. Different environmental conditions tested during production did not affect Salmonella viability; this demonstrated the broad adaptability of Salmonella and emphasized the need for methods that enable efficient monitoring of production for the presence of this pathogen.
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Affiliation(s)
- Seockmo Ku
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana
| | - Eduardo Ximenes
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana.,Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana
| | - Thomas Kreke
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana
| | - Kirk Foster
- Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
| | - Justin L Couetil
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana
| | - Jessica Zuponcic
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana.,Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana
| | - Xiaojun Zhao
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana
| | - Lori Hoagland
- Department of Horticulture and Landscape Architecture, Purdue University, West Lafayette, Indiana
| | - Amanda J Deering
- Department of Food Science, Purdue University, West Lafayette, Indiana
| | - Michael R Ladisch
- Laboratory of Renewable Resources Engineering, Purdue University, West Lafayette, Indiana.,Department of Agricultural and Biological Engineering, Purdue University, West Lafayette, Indiana.,Weldon School of Biomedical Engineering, Purdue University, West Lafayette, Indiana
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19
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Nachtigall C, Weber C, Rothenburger S, Jaros D, Rohm H. Test parameters and cell chain length of Streptococcus thermophilus affect the microbial adhesion to hydrocarbons assay: a methodical approach. FEMS Microbiol Lett 2019; 366:5528314. [DOI: 10.1093/femsle/fnz150] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2019] [Accepted: 07/01/2019] [Indexed: 01/01/2023] Open
Abstract
ABSTRACTThe microbial adhesion to hydrocarbons (MATH) test is one of the most common method to determine the hydrophobicity of cell surfaces. Despite its prevalence, no standard test parameters are used in literature, making a direct comparison of data almost impossible. Criticism also focuses on test parameters that may mask hydrophobic interactions and hence lead to erroneous test results. We methodically investigated the impact of different MATH test parameters on the calculation of the cell surface hydrophobicity of Streptococcus thermophilus, a widespread exopolysaccharide-producing lactic acid bacterium used in the production of fermented milk products. Besides composition and ionic strength of the buffer used for cell re-suspension, we observed a pronounced time dependency of the turbidity of the cell suspension during phase separation due to sedimentation and/or cell lysis. A new modification of the MATH assay was applied to enable the determination of cell surface hydrophobicity of long chain-forming bacteria. As the cell surface hydrophobicity was not altered during exponential growth phase, we assume that the cell surface and its capsular exopolysaccharide layer are not changed during cultivation.
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Affiliation(s)
- Carsten Nachtigall
- Chair of Food Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, D-01062 Dresden, Germany
| | - Carmen Weber
- Chair of Food Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, D-01062 Dresden, Germany
| | - Sandra Rothenburger
- Chair of Food Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, D-01062 Dresden, Germany
| | - Doris Jaros
- Chair of Food Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, D-01062 Dresden, Germany
| | - Harald Rohm
- Chair of Food Engineering, Institute of Natural Materials Technology, Technische Universität Dresden, D-01062 Dresden, Germany
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20
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Asvapathanagul P, Garrido-Baserba M, Olson BH, Park HD, Chen D, Rosso D. Comparison of DNA Extraction Efficiency and Reproducibility of Different Aeration Diffuser Biofilms Using Bead-Beating Protocol. J Mol Microbiol Biotechnol 2019; 28:293-304. [PMID: 31234170 DOI: 10.1159/000500875] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/02/2018] [Accepted: 05/06/2019] [Indexed: 11/19/2022] Open
Abstract
An existing bead-beating DNA extraction protocol was employed to compare the DNA extraction recovery and fragment quality of 6 different aeration diffuser biofilms. Escherichia coli, Gordonia amarae, and mixed liquor were used as controls. The fraction of total DNAbiofilm decreased monotonically with increasing number of beat beatings (BB) when the amount of DNA present was sufficient (>4 μgDNA/cm2), excluding the ceramic disk. While controls required only 2 BBs, 3 out of 5 BBs achieved ≥70% of total DNA (70.3 ± 1.7%) for 5 out of 6 biofilms. Quantitative polymerase chain reaction (PCR) analyses of 353 and 1,505 basepair (bp) amplicons from pure culture extracts showed target copy numbers were not degraded for the first 2 BBs, but the third BB decreased amplicon concentrations by 0.65 and 1.12 log for E. coli, and 0.39 and 0.40 log for G. amarae, respectively. The 353 bp fragment amplification from biofilm samples showed minimal degradation for the first 3 BBs. PCR and gel electrophoresis confirmed integrity of amplified 1,505 bp DNA fragments over the 5 BBs, except in the EDPM (75 mm diameter, tube) diffuser biofilm (4.98 ± 0.62 μgDNA/cm2). Taken together, this study showed type of diffuser membrane biofilms had no effects on extraction efficiency, but low DNA concentrations reduced extraction performance.
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Affiliation(s)
- Pitiporn Asvapathanagul
- Department of Civil Engineering and Construction Engineering Management, California State University, Long Beach, California, USA,
| | - Manel Garrido-Baserba
- Department of Civil and Environmental Engineering, University of California, Irvine, California, USA.,Water-Energy Nexus Center, University of California, Irvine, California, USA
| | - Betty H Olson
- Department of Civil and Environmental Engineering, University of California, Irvine, California, USA.,Water-Energy Nexus Center, University of California, Irvine, California, USA
| | - Hee-Deung Park
- School of Civil, Environmental and Architectural Engineering, Korea University, Seoul, Republic of Korea
| | - Deqiang Chen
- College of Environment, Hohai University, Nanjing, China
| | - Diego Rosso
- Department of Civil and Environmental Engineering, University of California, Irvine, California, USA.,Water-Energy Nexus Center, University of California, Irvine, California, USA
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21
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Yuan H, Zhang X, Jiang Z, Chen X, Zhang X. Quantitative Criterion to Predict Cell Adhesion by Identifying Dominant Interaction between Microorganisms and Abiotic Surfaces. LANGMUIR : THE ACS JOURNAL OF SURFACES AND COLLOIDS 2019; 35:3524-3533. [PMID: 30580526 DOI: 10.1021/acs.langmuir.8b03465] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Cell adhesion is ubiquitous and plays an important role in various scientific and engineering problems. Herein, a quantitative criterion to predict cell adhesion was proposed by identifying the dominant interaction between microorganisms and abiotic surfaces. According to the criterion, the dominant interaction in cell adhesion could be identified as a Lewis acid-base (AB) interaction or electrostatic (EL) interaction via comparison of two expressions containing the electron-donor characteristics of the microorganism (γmv-) and abiotic surface (γsv-) and their ζ potentials (ζm, ζs). The results revealed that when dominated by the AB interaction, adhesion would decrease with increasing [Formula: see text]. However, when the EL interaction was dominant, adhesion would decrease with increasing (ζm + ζs)2. We have verified the criterion based on the adhesion of microalgae, bacteria, and fungi onto various surfaces obtained via our experiments and available in literature studies. The results demonstrated that the criterion had important implications in the prediction of cell adhesion in various applications.
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22
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Garrido-Baserba M, Asvapathanagul P, Park HD, Kim TS, Baquero-Rodriguez GA, Olson BH, Rosso D. Impact of fouling on the decline of aeration efficiency under different operational conditions at WRRFs. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 639:248-257. [PMID: 29787908 DOI: 10.1016/j.scitotenv.2018.05.036] [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: 02/25/2018] [Revised: 05/02/2018] [Accepted: 05/03/2018] [Indexed: 06/08/2023]
Abstract
Biofilm formation influences the most energy-demanding process in the waste water treatment cycle. Biofilm growth on the surface of wastewater aeration diffusers in water resource recovery facilities (WRRFs) can increase the energy requirements up to 50% in less than 2 years. The impact of biofilms in aeration diffusers was quantified and assessed for first time using molecular tools (i.e., Energy-dispersive X-ray, Ra and RMS and Pyrosequencing) and state-of-the-art techniques (i.e., EPS quantification, Hydrophobicity and DNA quantification). To provide a better understanding and quantitative connections between biological activity and aeration energy efficiency, two replicates of the most common diffusers were installed and tested in two different operational conditions (higher and lower organic loading rate processes) during 15 months. Different scenarios and conditions provided for first time comprehensive understanding of the major factors contributing to diffuser fouling. The array of analysis suggested that higher loading conditions can promote specialized microbial populations to halve aeration efficiency parameters (i.e., αF) in comparison to lower loading conditions. Biofilms adapted to certain operational conditions can trigger changes in diffuser membrane properties (i.e., biological enhanced roughness and hydrophobicity) and enhance EPS growth rates. Improved understanding of the effects of scaling, biofouling, aging and microbial population shifts on the decrease in aeration efficiency is provided.
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Affiliation(s)
- Manel Garrido-Baserba
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA.
| | - Pitiporn Asvapathanagul
- Department of Civil Engineering and Construction Engineering Management, California State University, Long Beach, CA 90840, USA
| | - Hee-Deung Park
- School of Civil, Environmental and Architectural Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713, Republic of Korea
| | - Taek-Seung Kim
- School of Civil, Environmental and Architectural Engineering, Korea University, Anam-Dong, Seongbuk-Gu, Seoul 136-713, Republic of Korea
| | - G Andres Baquero-Rodriguez
- Facultad de Ingeniería, Universidad Militar Nueva Granada, Sede Campus Nueva Granada, Km 2, vía Cajicá - Zipaquirá, Colombia
| | - Betty H Olson
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, (USA)
| | - Diego Rosso
- Department of Civil & Environmental Engineering, University of California, Irvine, CA 92697-2175, USA; Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, (USA)
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23
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Jiang XT, Ye L, Ju F, Wang YL, Zhang T. Toward an Intensive Longitudinal Understanding of Activated Sludge Bacterial Assembly and Dynamics. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2018; 52:8224-8232. [PMID: 29943968 DOI: 10.1021/acs.est.7b05579] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Temporal microbial community studies have broadened our knowledge of the dynamics and correlations among microbes in both natural and artificial engineering systems. Using activated sludge as a model system, we utilized the intensive longitudinal sampling method to identify overlooked diversity and the hidden dynamics of microbes, detect cross-associations among microbes after detrending, and reveal the central microbial dynamics during sludge bulking and foaming. We discovered that the accumulative alpha diversity in activated sludge sampled daily over 392 days could be as high as 14 000 OTUs, and that the bacterial community dynamics followed a gradual succession, drifting away from the initial observed day and displaying a significant time-dependent trend. Cross-associations among bacteria were modulated after removing potential spurious correlations based on autocorrelation in microbial time series. Moreover, clusters of bacteria displaying rapid turnover were discovered during the beginning, ongoing, and fading of sludge bulking and foaming, and their physicochemical parameters are resolved. These identified groups of bacteria and their related environmental factors could potentially supply clues to form hypotheses for treating operational problems, such as sludge bulking and foaming.
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Affiliation(s)
- Xiao-Tao Jiang
- Environmental Biotechnology Lab , The University of Hong Kong , Pokfulam , Hong Kong , SAR China
| | - Lin Ye
- Environmental Biotechnology Lab , The University of Hong Kong , Pokfulam , Hong Kong , SAR China
| | - Feng Ju
- Environmental Biotechnology Lab , The University of Hong Kong , Pokfulam , Hong Kong , SAR China
| | - Yu-Lin Wang
- Environmental Biotechnology Lab , The University of Hong Kong , Pokfulam , Hong Kong , SAR China
| | - Tong Zhang
- Environmental Biotechnology Lab , The University of Hong Kong , Pokfulam , Hong Kong , SAR China
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24
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Pourakbar M, Moussavi G, Yaghmaeian K. Enhanced biodegradation of phenol in a novel cyclic activated sludge integrated with a rotating bed bioreactor in anoxic and peroxidase-mediated conditions. RSC Adv 2018; 8:6293-6305. [PMID: 35540395 PMCID: PMC9078260 DOI: 10.1039/c7ra12997a] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/03/2017] [Accepted: 01/23/2018] [Indexed: 11/21/2022] Open
Abstract
Cyclic activated sludge integrated with a rotating bed bioreactor (CASIR) was used for phenol biodegradation. The effects of phenol loading rate, mixed liquor suspended solids (MLSS) concentration, media filling ratio, hydraulic retention time (HRT) and salinity were investigated for phenol degradation and COD removal. In the second phase of the study, the microbial content of the bioreactor was induced by hydrogen peroxide injection for in situ generation of peroxidase. For investigating the above-mentioned parameters, the bioreactor was operated for 535 days and residual phenol, nitrate and COD were measured daily. The variation of the dehydrogenase activity and peroxidase activity of suspended biomass and attached film were also monitored during the bioreactor operation. Complete degradation of phenol at the loading rate of 667 g m−3 d−1 was achieved in anoxic conditions. Addition of media to the bioreactor to form active attached biofilm led to the increase in tolerance of the bioreactor on organic loading shocks. It was found that increasing the salinity of the wastewater did not affect the performance of the bioreactor. Investigating dehydrogenase activity proved that the attached biofilm was more involved in phenol degradation, compared with the suspended biomass. However, after switching to peroxidase-mediated conditions, the organic loading tolerance of the bioreactor considerably increased and complete degradation of phenol at the loading rate of 2000 g m−3 d−1 was reached. After adaptation of the microorganisms for hydrogen peroxide, the peroxidase activity of 290 U gbiomass−1 was observed in the bioreactor. Accordingly, the H2O2-induced microbial cells in cyclic activated sludge could be considered as a promising technique for enzymatic degradation of phenol and corresponding COD. Cyclic activated sludge integrated with a rotating bed bioreactor (CASIR) was used for phenol biodegradation.![]()
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Affiliation(s)
- Mojtaba Pourakbar
- Department of Environmental Health Engineering
- Faculty of Medical Sciences
- Tarbiat Modares University
- Tehran
- Iran
| | - Gholamreza Moussavi
- Department of Environmental Health Engineering
- Faculty of Medical Sciences
- Tarbiat Modares University
- Tehran
- Iran
| | - Kamyar Yaghmaeian
- Department of Environmental Health Engineering
- School of Public Health
- Tehran University of Medical Sciences
- Tehran
- Iran
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25
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Corsino SF, Capodici M, Torregrossa M, Viviani G. Fate of aerobic granular sludge in the long-term: The role of EPSs on the clogging of granular sludge porosity. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2016; 183:541-550. [PMID: 27623364 DOI: 10.1016/j.jenvman.2016.09.004] [Citation(s) in RCA: 29] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2016] [Revised: 08/30/2016] [Accepted: 09/01/2016] [Indexed: 06/06/2023]
Abstract
This work aims to investigate the stability of aerobic granular sludge in the long term, focusing on the clogging of the granular sludge porosity exerted by the extracellular polymeric substances (EPSs). The effects of different cycle lengths (short and long-term cycle) on the granular sludge stability were investigated. Results obtained outlined that during the short duration cycle, the formation and breakage of the aerobic granules were continuously observed. During this period, the excess of EPS production contributed to the clogging of the granules porosity, causing their breakage in the long run. During the long-duration cycle, the extended famine period entailed a greater EPSs consumption by bacteria, thus limiting the clogging of the porosity, and allowed obtaining stable aerobic granules. Reported results demonstrated that an excess in EPSs content could be detrimental to the stability of aerobic granular sludge in the long-term.
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Affiliation(s)
- Santo Fabio Corsino
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy.
| | - Marco Capodici
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
| | - Michele Torregrossa
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
| | - Gaspare Viviani
- Dipartimento di Ingegneria Civile, Ambientale, Aerospaziale, dei Materiali, Università di Palermo, Viale delle Scienze, 90128, Palermo, Italy
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26
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Zhang P, Guo JS, Shen Y, Yan P, Chen YP, Wang H, Yang JX, Fang F, Li C. Microbial communities, extracellular proteomics and polysaccharides: A comparative investigation on biofilm and suspended sludge. BIORESOURCE TECHNOLOGY 2015; 190:21-28. [PMID: 25919933 DOI: 10.1016/j.biortech.2015.04.058] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/26/2015] [Revised: 04/14/2015] [Accepted: 04/16/2015] [Indexed: 06/04/2023]
Abstract
Biofilm and suspended sludge (S-sludge) floc exhibit distinct physicochemical properties and process performances in an integrated fixed-film and suspended growth sequencing batch reactor. However, the mechanisms of governing these differences between the two aggregates were unknown. Current work evaluated the diversity of morphologies, microbial communities, extracellular proteins and polysaccharides between the biofilm and S-sludge. Contrast to biofilm, the denitrification was much more extensive performed in S-sludge. Furthermore, many microbial cells in the biofilm acted as the backbone of aggregates and maintained the structure stability. An extracellular protein observed only in the biofilm can promote the cell adhesion. In contrast, more extracellular proteins related to catalytic activity in the S-sludge could decrease the compactness of floc. In addition, the monosaccharide compositions from the two aggregates were various. These results could elucidate how the diversities of architecture and biochemical process between the two aggregates occurred.
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Affiliation(s)
- Peng Zhang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China
| | - Jin-Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Yu Shen
- Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Peng Yan
- Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - You-Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China; Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China.
| | - Han Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China
| | - Ji-Xiang Yang
- Key Laboratory of Reservoir Aquatic Environment of CAS, Chongqing Institute of Green and Intelligent Technology, Chinese Academy of Sciences, Chongqing 400714, China
| | - Fang Fang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China
| | - Chun Li
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environments of MOE, Chongqing University, Chongqing 400045, China
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27
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Li F, Zhu L, Wang L, Zhan Y. Gene expression of an arthrobacter in surfactant-enhanced biodegradation of a hydrophobic organic compound. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2015; 49:3698-3704. [PMID: 25680000 DOI: 10.1021/es504673j] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
Surfactants can affect the biodegradation process and the fate of hydrophobic organic compounds (HOCs) in the environment. Previous studies have shown that surfactants can enhance the biodegradation of HOCs by increasing cell surface hydrophobicity (CSH) and membrane fluidity. In this study, we took this work one step further by investigating the expression levels of three genes of Arthrobacter sp. SA02 in the biodegradation of phenanthrene as a typical HOC at different concentrations of sodium dodecyl benzenesulfonate (SDBS), which is a widely used surfactant. The Δ9 fatty acid desaturase gene codes for Δ9 fatty acid desaturase, which can convert saturated fatty acid to its unsaturated form. The ring-hydroxylating dioxygenase (RHDase) and the 1-hydroxyl-2-naphthoate dioxygenase (1H2Nase) genes code for the RHDase and 1H2Nase enzymes, respectively, which play a key role in decomposing doubly hydroxylated aromatic compounds. The results show that these three genes were upregulated in the presence of SDBS. On the basis of the genetic and physiological changes, we proposed a pathway that links the gene expression with the physiological phenomena, including CSH, membrane fluidity, and intracellular degradation. This study advances our understanding of the surfactant-enhanced biodegradation of HOCs at the gene level, and the proposed pathway should be further validated in the future.
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Affiliation(s)
- Feng Li
- †Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- ‡Zhejiang Provincial Key Laboratory of Organic Pollution Process Control, Hangzhou 310058, China
- §Department of Environmental Science and Engineering, Xiangtan University, Xiangtan 411105, China
| | - Lizhong Zhu
- †Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- ‡Zhejiang Provincial Key Laboratory of Organic Pollution Process Control, Hangzhou 310058, China
| | - Lingwen Wang
- †Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- ‡Zhejiang Provincial Key Laboratory of Organic Pollution Process Control, Hangzhou 310058, China
| | - Yu Zhan
- †Department of Environmental Science, Zhejiang University, Hangzhou 310058, China
- ‡Zhejiang Provincial Key Laboratory of Organic Pollution Process Control, Hangzhou 310058, China
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