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Chen Y, Zhou H, Gao H, Su Z, Li X, Qi P, Li T, Hu C, Li Z, Bi Z, Xing X, Yang J, Chen C, Ma K, Chen J. Comprehensive comparison of water quality risk and microbial ecology between new and old cast iron pipe distribution systems. J Environ Sci (China) 2024; 146:55-66. [PMID: 38969462 DOI: 10.1016/j.jes.2023.05.020] [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: 04/01/2023] [Revised: 05/11/2023] [Accepted: 05/12/2023] [Indexed: 07/07/2024]
Abstract
The effects of cast iron pipe corrosion on water quality risk and microbial ecology in drinking water distribution systems (DWDSs) were investigated. It was found that trihalomethane (THMs) concentration and antibiotic resistance genes (ARGs) increased sharply in the old DWDSs. Under the same residual chlorine concentration conditions, the adenosine triphosphate concentration in the effluent of old DWDSs (Eff-old) was significantly higher than that in the effluent of new DWDSs. Moreover, stronger bioflocculation ability and weaker hydrophobicity coexisted in the extracellular polymeric substances of Eff-old, meanwhile, iron particles could be well inserted into the structure of the biofilms to enhance the mechanical strength and stability of the biofilms, hence enhancing the formation of THMs. Old DWDSs significantly influenced the microbial community of bulk water and triggered stronger microbial antioxidant systems response, resulting in higher ARGs abundance. Corroded cast iron pipes induced a unique interaction system of biofilms, chlorine, and corrosion products. Therefore, as the age of cast iron pipes increases, the fluctuation of water quality and microbial ecology should be paid more attention to maintain the safety of tap water.
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Affiliation(s)
- Youyi Chen
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Huishan Zhou
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Hui Gao
- Zhejiang Xingtuo Ecological Environment Co., Ltd., Hangzhou 310051, China
| | - Ziliang Su
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xinjun Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Peng Qi
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Tong Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Chun Hu
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zesong Li
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Zhihao Bi
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xueci Xing
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Jingxin Yang
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Chaoxiang Chen
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
| | - Kunyu Ma
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
| | - Jinrong Chen
- Nanzhou Waterworks of Guangzhou Water Supply Co. Ltd., Guangzhou 510000, China
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Wang XP, Han NN, Xu ZY, Zhu YH, Li GF, Fan NS, Jin RC. Quorum sensing mediated response mechanism of anammox consortia to anionic surfactant: Molecular simulation and molecular evidence. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 945:174121. [PMID: 38901593 DOI: 10.1016/j.scitotenv.2024.174121] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/27/2024] [Revised: 06/16/2024] [Accepted: 06/16/2024] [Indexed: 06/22/2024]
Abstract
The widespread use of surfactants raise challenges to biological wastewater treatment. Anaerobic ammonium oxidation (anammox) process has the potential to treat wastewater containing anionic surfactants, but the response of anammox consortia at the molecular level under long-term exposure is unclear. Using high-throughput sequencing and gene quantification, combined with molecular docking, the effect of sodium dodecyl sulfonate (SDS) on anammox consortia were investigated. Levels of reactive oxygen species (ROS) might be lower than the threshold of oxidative damage, while the increase of lactate dehydrogenase (LDH) represented the cell membrane damage. Decreased abundance of functional genes (hdh, hzsA and nirS) indicated the decrease of the anammox bacterial abundance. Trace amounts of N-acyl homoserine lactone (AHL, C6-HSL, C8-HSL and C12-HSL) contained in influent could induce endogenous quorum sensing (QS), which could regulate the correlation between functional bacteria to optimize the microbial community and strengthen the resistance of anammox consortia to SDS. In addition, the proliferation of disinfectant resistance genes might increase the environmental pathogenicity of sewage discharge. This work highlights the potential response mechanism of anammox consortium to surfactants and provides a universal microbial-friendly bioenhancement strategy based on QS.
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Affiliation(s)
- Xue-Ping Wang
- School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Na-Na Han
- School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Zi-Yan Xu
- School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Yu-Hui Zhu
- School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Gui-Feng Li
- State Key Laboratory of Urban Water Resource and Environment, School of Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Nian-Si Fan
- School of Engineering, Hangzhou Normal University, Hangzhou 311121, China; School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China
| | - Ren-Cun Jin
- School of Engineering, Hangzhou Normal University, Hangzhou 311121, China; School of Life and Environmental Sciences, Hangzhou Normal University, Hangzhou 311121, China.
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Feng C, Bonetti L, Lu H, Zhou Z, Lotti T, Jia M, Rizzardi G, De Nardo L, Malpei F. Extracellular polymeric substances as paper coating biomaterials derived from anaerobic granular sludge. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 21:100397. [PMID: 38434491 PMCID: PMC10904903 DOI: 10.1016/j.ese.2024.100397] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2023] [Revised: 01/21/2024] [Accepted: 01/22/2024] [Indexed: 03/05/2024]
Abstract
Recovering extracellular polymeric substances (EPS) from waste granular sludge offers a cost-effective and sustainable approach for transforming wastewater resources into industrially valuable products. Yet, the application potential of these EPS in real-world scenarios, particularly in paper manufacturing, remains underexplored. Here we show the feasibility of EPS-based biomaterials, derived from anaerobic granular sludges, as novel coating agents in paper production. We systematically characterised the rheological properties of various EPS-based suspensions. When applied as surface sizing agents, these EPS-based biomaterials formed a distinct, ultra-thin layer on paper, as evidenced by scanning electron microscopy. A comprehensive evaluation of water and oil penetration, along with barrier properties, revealed that EPS-enhanced coatings markedly diminished water absorption while significantly bolstering oil and grease resistance. Optimal performance was observed in EPS variants with elevated protein and hydrophobic contents, correlating with their superior rheological characteristics. The enhanced water-barrier and grease resistance of EPS-coated paper can be attributed to its non-porous, fine surface structure and the functional groups in EPS, particularly the high protein content and hydrophobic humic-like substances. This research marks the first demonstration of utilizing EPS from anaerobic granular sludge as paper-coating biomaterials, bridging a critical knowledge gap in the sustainable use of biopolymers in industrial applications.
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Affiliation(s)
- Cuijie Feng
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133, Milan, Italy
- School of Civil Engineering, Sun Yat-sen University, 519082, Zhuhai, China
| | - Lorenzo Bonetti
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli, 7, 20131, Milan, Italy
| | - Hui Lu
- School of Environmental Science and Engineering, Sun Yat-sen University, 510275, Guangzhou, China
| | - Zhongbo Zhou
- Southwest University, College of Resources and Environment, Tiansheng Road 2, Beibei District, 400716, Chongqing, China
| | - Tommaso Lotti
- Civil and Environmental Engineering Department, University of Florence, Via di Santa Marta 3, 50139, Florence, Italy
| | - Mingsheng Jia
- Center for Microbial Ecological and Technology (CMET), Ghent University, Coupure Links 653, Gent, Belgium
| | - Giacomo Rizzardi
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133, Milan, Italy
| | - Luigi De Nardo
- Department of Chemistry, Materials and Chemical Engineering “G. Natta”, Politecnico di Milano, Via Mancinelli, 7, 20131, Milan, Italy
| | - Francesca Malpei
- Department of Civil and Environmental Engineering, Politecnico di Milano, Piazza Leonardo da Vinci, 32, 20133, Milan, Italy
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Xu C, Feng Y, Li H, Liu M, Yao Y, Li Y. Enhanced degradation of enrofloxacin in mariculture wastewater based on marine bacteria and microbial carrier. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134555. [PMID: 38728864 DOI: 10.1016/j.jhazmat.2024.134555] [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: 02/10/2024] [Revised: 03/28/2024] [Accepted: 05/04/2024] [Indexed: 05/12/2024]
Abstract
This study aimed to isolate marine bacteria to investigate their stress response, inhibition mechanisms, and degradation processes under high-load conditions of salinity and enrofloxacin (ENR). The results demonstrated that marine bacteria exhibited efficient pollutant removal efficiency even under high ENR stress (up to 10 mg/L), with chemical oxygen demand (COD), total phosphorus (TP), total nitrogen (TN) and ENR removal efficiencies reaching approximately 88%, 83%, 61%, and 73%, respectively. The predominant families of marine bacteria were Bacillaceae (50.46%), Alcanivoracaceae (32.30%), and Rhodobacteraceae (13.36%). They responded to ENR removal by altering cell membrane properties, stimulating the activity of xenobiotic-metabolizing enzymes and antioxidant systems, and mitigating ENR stress through the secretion of extracellular polymeric substance (EPS). The marine bacteria exhibited robust adaptability to environmental factors and effective detoxification of ENR, simultaneously removing carbon, nitrogen, phosphorus, and antibiotics from the wastewater. The attapulgite carrier enhanced the bacteria's resistance to the environment. When treating actual mariculture wastewater, the removal efficiencies of COD and TN exceeded 80%, TP removal efficiency exceeded 90%, and ENR removal efficiency approached 100%, significantly higher than reported values in similar salinity reactors. Combining the constructed physical and mathematical models of tolerant bacterial, this study will promote the practical implementation of marine bacterial-based biotechnologies in high-loading saline wastewater treatment.
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Affiliation(s)
- Chenglong Xu
- School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China; State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yali Feng
- School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China.
| | - Haoran Li
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China; University of Chinese Academy of Sciences, Beijing 100049, China.
| | - Mengyao Liu
- School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yisong Yao
- School of Civil and Resource Engineering, University of Science and Technology Beijing, Beijing 100083, China
| | - Yunhao Li
- State Key Laboratory of Biochemical Engineering, Institute of Process Engineering, Chinese Academy of Sciences, Beijing 100190, China
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5
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Zeng Y, Wang Z, Tan Q, Shen Y, Sun J, Shen L, Teng J, Lin H. Enhanced sludge dewatering using a novel synergistic iron/peroxymonosulfate-polyacrylamide method. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 365:121638. [PMID: 38959766 DOI: 10.1016/j.jenvman.2024.121638] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/21/2024] [Revised: 06/17/2024] [Accepted: 06/27/2024] [Indexed: 07/05/2024]
Abstract
In the sludge dewatering process, a formidable challenge arises due to the robust interactions between extracellular polymeric substances (EPS) and bound water. This study introduces a novel, synergistic conditioning method that combines iron (Fe2+)/peroxymonosulfate (PMS) and polyacrylamide (PAM) to significantly enhance sludge dewatering efficiency. The application of the Fe2+/PMS-PAM conditioning method led to a substantial reduction in specific filtration resistance (SFR) by 82.75% and capillary suction time (CST) by 80.44%, marking a considerable improvement in dewatering performance. Comprehensive analyses revealed that pre-oxidation with Fe2+/PMS in the Fe2+/PMS-PAM process effectively degraded EPS, facilitating the release of bound water. Subsequently, PAM enhanced the flocculation of fine sludge particles resulting from the advanced oxidation processes (AOPs). Furthermore, analysis based on the Extended Derjaguin-Landau-Verwey-Overbeek (XDLVO) theory demonstrated shifts in interaction energies, highlighting the breakdown of energy barriers within the sludge and a transition in surface characteristics from hydrophilic (3.79 mJ m-2) to hydrophobic (-61.86 mJ m-2). This shift promoted the spontaneous aggregation of sludge particles. The innovative use of the Flory-Huggins theory provided insights into the sludge filtration mechanism from a chemical potential perspective, linking these changes to SFR. The introduction of Fe2+/PMS-PAM conditioning disrupted the uniformity of the EPS-formed gel layer, significantly reducing the chemical potential difference between the permeate and the water in the gel layer, leading to a lower SFR and enhanced dewatering performance. This thermodynamic approach significantly enhances our understanding of sludge dewatering and conditioning. These findings represent a paradigm shift, offering innovative strategies for sludge treatment and expanding our comprehension of dewatering and conditioning techniques.
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Affiliation(s)
- Yansha Zeng
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Zhe Wang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Qiyin Tan
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Yue Shen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Jiahao Sun
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Liguo Shen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Jiaheng Teng
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
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Liu Z, Cui Z, Guo Z, Li D, He Z, Liu W, Yue X, Zhou A. Insights into the effect of nitrate photolysis on short-chain fatty acids production from waste activated sludge in anaerobic fermentation system: Performance and mechanisms. WATER RESEARCH 2024; 258:121772. [PMID: 38761600 DOI: 10.1016/j.watres.2024.121772] [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: 02/23/2024] [Revised: 04/20/2024] [Accepted: 05/12/2024] [Indexed: 05/20/2024]
Abstract
Nitrate photolysis has become an efficient, low-cost and promising technology for emerging contaminants removal, while its performance and mechanism for waste activated sludge (WAS) treatment is still unknown. This study innovatively introduced nitrate photolysis for WAS disintegration, and investigated the effect of nitrate addition (150-375 mg N/L) for short-chain fatty acids (SCFAs) production during anaerobic fermentation (AF). The results showed that nitrate photolysis significantly promoted the SCFAs production from WAS, and peaked at 280.7 mg/g VSS with 7-d fermentation with 150 mg N/L addition (150N-UV), which increased by 8.8-35.0 % and 10.7-23.3 % compared with other photolysis groups and sole nitrate groups. Effective release of the soluble organics was observed in the nitrate photolysis groups during AF, especially soluble proteins, reaching 1505.4 mg COD/L at 9 d in 150N-UV group, promoted by 7.0∼15.7 % than nitrate/nitrate photolysis groups. The model compounds simulation experiment further demonstrated the positive effect of nitrate photolysis on organics hydrolysis and SCFAs accumulation. The result of the radical capture and quenching verified the reactive oxygen species contributed more compared with reactive nitrogen species. Functional group analysis confirmed the effective bioconversion of the macromolecular organics during the fermentation. Moreover, the nitrate photolysis enhanced the enrichment of the functional consortia, including anaerobic fermentation bacteria (AFB), e.g., Fnoticella, Romboutsia, Gracilibacter and Sedimentibacter, and nitrate reducing bacteria (NRB), e.g., Acinerobacter and Ahniella. The macrogenetic analysis further revealed that glycolysis, amino acid metabolism, acetate metabolism and nitrogen metabolism were the dominating metabolic pathways during fermentation, and the abundance of the relevant genes were enhanced in 150N-UV group.
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Affiliation(s)
- Zhihong Liu
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China; Shanxi Academy of Advanced Research and Innovation, Taiyuan 030024, China
| | - Zhixuan Cui
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Zhengtong Guo
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China
| | - Dengfei Li
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China; Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan, China
| | - Zhangwei He
- School of Environment and Municipal Engineering, Xi'an University of Architecture and Technology, Shanxi 710055, China
| | - Wenzong Liu
- Civil and Environmental Engineering, Harbin Institute of Technology, Shenzhen 518055, China
| | - Xiuping Yue
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China; Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan, China
| | - Aijuan Zhou
- College of Environmental Science and Engineering, Taiyuan University of Technology, Taiyuan, China; Shanxi-Zheda Institute of Advanced Materials and Chemical Engineering, Taiyuan, China.
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Wang J, Ran B, Peng Y, An Q, Zhao B. Evaluation of aerobic granulation performance bioaugmented with the auto-aggregating bacterium Pseudomonas stutzeri strain XL-2 with heterotrophic nitrification-aerobic denitrification capacity. BIORESOURCE TECHNOLOGY 2024; 403:130869. [PMID: 38777236 DOI: 10.1016/j.biortech.2024.130869] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 04/27/2024] [Accepted: 05/19/2024] [Indexed: 05/25/2024]
Abstract
In this study, the possibility of an auto-aggregating bacterium Pseudomonas strain XL-2 with heterotrophic nitrification-aerobic denitrification capacity for improving granulation and nitrogen removal was evaluated. The results showed that the supplementation of strain XL-2 promoted granulation, making R1 (experimental group with strain XL-2) dominated by granules at 14 d, which was 12 days earlier than R2 (control group without strain XL-2). This was attributed to the promotion of extracellular polymeric substances (EPS) secretion, particularly proteins by adding strain XL-2, thereby improving the hydrophobicity of sludge and altering the proteins secondary structures to facilitate aggregation. Meanwhile, adding strain XL-2 improved simultaneous nitrification and denitrification efficiency of R1. Microbial community analysis indicated that strain XL-2 successfully proliferated in aerobic granule sludge and might induce the enrichment of genera such as Flavobacterium and Paracoccus that were favorable for EPS secretion and denitrification, jointly promoting granulation and enhancing nitrogen removal efficiency.
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Affiliation(s)
- Jinyi Wang
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Binbin Ran
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Yongxue Peng
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Qiang An
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China
| | - Bin Zhao
- The Key Laboratory of Eco-Environment in Three Gorges Reservoir Region, Chongqing University, Chongqing 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing 400045, PR China.
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8
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Wang Y, Guo H, Li X, Chen X, Peng L, Zhu T, Sun P, Liu Y. Peracetic acid (PAA)-based pretreatment effectively improves medium-chain fatty acids (MCFAs) production from sewage sludge. ENVIRONMENTAL SCIENCE AND ECOTECHNOLOGY 2024; 20:100355. [PMID: 38192428 PMCID: PMC10772567 DOI: 10.1016/j.ese.2023.100355] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 11/17/2023] [Accepted: 11/23/2023] [Indexed: 01/10/2024]
Abstract
Peracetic acid (PAA), known for its environmentally friendly properties as a oxidant and bactericide, is gaining prominence in decontamination and disinfection applications. The primary product of PAA oxidation is acetate that can serve as an electron acceptor (EA) for the biosynthesis of medium-chain fatty acids (MCFAs) via chain elongation (CE) reactions. Hence, PAA-based pretreatment is supposed to be beneficial for MCFAs production from anaerobic sludge fermentation, as it could enhance organic matter availability, suppress competing microorganisms and furnish EA by providing acetate. However, such a hypothesis has rarely been proved. Here we reveal that PAA-based pretreatment leads to significant exfoliation of extracellular polymeric substances (EPS) from sludge flocs and disruption of proteinic secondary structures, through inducing highly active free radicals and singlet oxygen. The production of MCFAs increases substantially to 11,265.6 mg COD L-1, while the undesired byproducts, specifically long-chain alcohols (LCAs), decrease to 723.5 mg COD L-1. Microbial activity tests further demonstrate that PAA pretreatment stimulates the CE process, attributed to the up-regulation of functional genes involved in fatty acid biosynthesis pathway. These comprehensive findings provide insights into the effectiveness and mechanisms behind enhanced MCFAs production through PAA-based technology, advancing our understanding of sustainable resource recovery from sewage sludge.
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Affiliation(s)
- Yufen Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Haixiao Guo
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Xuecheng Li
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Xueming Chen
- Fujian Provincial Engineering Research Center of Rural Waste Recycling Technology, College of Environment and Safety Engineering, Fuzhou University, Fujian, 350116, China
| | - Lai Peng
- Hubei Key Laboratory of Mineral Resources Processing and Environment, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China
- School of Resources and Environmental Engineering, Wuhan University of Technology, Luoshi Road 122, Wuhan, Hubei, 430070, China
| | - Tingting Zhu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Peizhe Sun
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin, 300072, China
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9
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Zhang X, Zhao J, Erler DV, Rabiee H, Kong Z, Wang S, Wang Z, Virdis B, Yuan Z, Hu S. Characterization of the redox-active extracellular polymeric substances in an anaerobic methanotrophic consortium. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 365:121523. [PMID: 38901321 DOI: 10.1016/j.jenvman.2024.121523] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2024] [Revised: 05/29/2024] [Accepted: 06/16/2024] [Indexed: 06/22/2024]
Abstract
Anaerobic oxidation of methane (AOM) is a microbial process of importance in the global carbon cycle. AOM is predominantly mediated by anaerobic methanotrophic archaea (ANME), the physiology of which is still poorly understood. Here we present a new addition to the current physiological understanding of ANME by examining, for the first time, the biochemical and redox-active properties of the extracellular polymeric substances (EPS) of an ANME enrichment culture. Using a 'Candidatus Methanoperedens nitroreducens'-dominated methanotrophic consortium as the representative, we found it can produce an EPS matrix featuring a high protein-to-polysaccharide ratio of ∼8. Characterization of EPS using FTIR revealed the dominance of protein-associated amide I and amide II bands in the EPS. XPS characterization revealed the functional group of C-(O/N) from proteins accounted for 63.7% of total carbon. Heme-reactive staining and spectroscopic characterization confirmed the distribution of c-type cytochromes in this protein-dominated EPS, which potentially enabled its electroactive characteristic. Redox-active c-type cytochromes in EPS mediated the EET of 'Ca. M. nitroreducens' for the reduction of Ag+ to metallic Ag, which was confirmed by both ex-situ experiments with extracted soluble EPS and in-situ experiments with pristine EPS matrix surrounding cells. The formation of nanoparticles in the EPS matrix during in-situ extracellular Ag + reduction resulted in a relatively lower intracellular Ag distribution fraction, beneficial for alleviating the Ag toxicity to cells. The results of this study provide the first biochemical information on EPS of anaerobic methanotrophic consortia and a new insight into its physiological role in AOM process.
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Affiliation(s)
- Xueqin Zhang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia
| | - Jing Zhao
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia; Ecological Engineering of Mine Wastes, Sustainable Minerals Institute, The University of Queensland, Brisbane, Queensland, Australia
| | - Dirk V Erler
- Faculty of Science and Engineering, Southern Cross University, Lismore, NSW, Australia
| | - Hesamoddin Rabiee
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia; School of Chemical Engineering, The University of Queensland, Brisbane, Queensland, Australia; Centre for Future Materials, University of Southern Queensland, Springfield, Queensland, Australia
| | - Zheng Kong
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia
| | - Suicao Wang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia
| | - Zhiyao Wang
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia
| | - Bernardino Virdis
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia
| | - Zhiguo Yuan
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia; School of Energy and Environment, City University of Hong Kong, Hong Kong SAR, China
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology, The University of Queensland, Brisbane, Queensland, Australia.
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10
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Wang L, Lei Z, Zhang Z, Yang X, Chen R. Deciphering the role of extracellular polymeric substances in the adsorption and biotransformation of organic micropollutants during anaerobic wastewater treatment. WATER RESEARCH 2024; 257:121718. [PMID: 38723358 DOI: 10.1016/j.watres.2024.121718] [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: 02/28/2024] [Revised: 04/20/2024] [Accepted: 05/02/2024] [Indexed: 05/29/2024]
Abstract
Extracellular polymeric substances (EPS) participate in the removal of organic micropollutants (OMPs), but the primary pathways of removal and detailed mechanisms remain elusive. We evaluated the effect of EPS on removal for 16 distinct chemical classes of OMPs during anaerobic digestion (AD). The results showed that hydrophobic OMPs (HBOMPs) could not be removed by EPS, while hydrophilic OMPs (HLOMPs) were amenable to removal via adsorption and biotransformation of EPS. The adsorption and biotransformation of HLOMPs by EPS accounted up to 19.4 ± 0.9 % and 6.0 ± 0.8 % of total removal, respectively. Further investigations into the adsorption and biotransformation mechanisms of HLOMPs by EPS were conducted utilizing spectral, molecular dynamics simulation, and electrochemical analysis. The results suggested that EPS provided abundant binding sites for the adsorption of HLOMPs. The binding of HLOMPs to tryptophan-like proteins in EPS formed nonfluorescent complexes. Hydrogen bonds, hydrophobic interactions and water bridges were key to the binding processes and helped stabilize the complexes. The biotransformation of HLOMPs by EPS may be attributed to the presence of extracellular redox active components (c-type cytochromes (c-Cyts), c-Cyts-bound flavins). This study enhanced the comprehension for the role of EPS on the OMPs removal in anaerobic wastewater treatment.
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Affiliation(s)
- Lianxu Wang
- Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China
| | - Zhen Lei
- Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China
| | - Zixin Zhang
- Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China
| | - Xiaohuan Yang
- Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China
| | - Rong Chen
- Key Lab of Environmental Engineering, Shaanxi Province, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China; International S&T Cooperation Center for Urban Alternative Water Resources Development, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, No.13 Yanta Road, Xi'an 710055, PR China.
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11
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Liu D, Zhang Z, Zhang Z, Yang J, Chen W, Liu B, Lu J. The fate of pharmaceuticals and personal care products (PPCPs) in sewer sediments:Adsorption triggering resistance gene proliferation. JOURNAL OF HAZARDOUS MATERIALS 2024; 471:134255. [PMID: 38669934 DOI: 10.1016/j.jhazmat.2024.134255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/09/2024] [Revised: 03/18/2024] [Accepted: 04/08/2024] [Indexed: 04/28/2024]
Abstract
In recent years, large quantities of pharmaceuticals and personal care products (PPCPs) have been discharged into sewers, while the mechanisms of PPCPs enrichment in sewer sediments have rarely been revealed. In this study, three PPCPs (tetracycline, sulfamethoxazole, and triclocarban) were added consecutively over a 90-day experimental period to reveal the mechanisms of PPCPs enrichment and the transmission of resistance genes in sewer sediments. The results showed that tetracycline (TC) and triclocarban (TCC) have higher adsorption concentration in sediments compared to sulfamethoxazole (SMX). The absolute abundance of Tets and suls genes increased in sediments under PPCPs pressure. The increase in secretion of extracellular polymeric substances (EPS) and the loosening of the structure exposed a large number of hydrophobic functional groups, which promoted the adsorption of PPCPs. The absolute abundance of antibiotic resistance genes (ARGs), EPS and the content of PPCPs in sediments exhibited significant correlations. The enrichment of PPCPs in sediments was attributed to the accumulation of EPS, which led to the proliferation of ARGs. These findings contributed to further understanding of the fate of PPCPs in sewer sediments and opened a new perspective for consideration of controlling the proliferation of resistance genes.
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Affiliation(s)
- Duoduo Liu
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Zigeng Zhang
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Zhiqiang Zhang
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Jing Yang
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Wentao Chen
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Bo Liu
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China
| | - Jinsuo Lu
- Environmental and Municipal Engineering Department, Xi' an University of Architecture and Technology, Xi'an, Shaanxi, China; Key Laboratory of Northwest Water Resources, Environment and Ecology, Ministry of Education, China; Key Laboratory of Environmental Engineering, Shaanxi, China.
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12
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Wang C, Qi WK, Zhang SJ, Liu LF, Peng YZ. Innovation for continuous aerobic granular sludge process in actual municipal sewage treatment: Self-circulating up-flow fluidized bed process. WATER RESEARCH 2024; 260:121862. [PMID: 38908310 DOI: 10.1016/j.watres.2024.121862] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/05/2024] [Revised: 05/28/2024] [Accepted: 05/31/2024] [Indexed: 06/24/2024]
Abstract
Aerobic granular sludge (AGS) capable of nitrogen and phosphorus removal is mainly limited to the applications in sequencing batch reactors. This study introduced an innovative continuous self-circulating up-flow fluidized bed process (Zier process) using separate aeration. The process was composed of an anoxic column (Zier-A), aeration column (Zier-OO) and aerobic column (Zier-O), and was used to treat actual municipal sewage continuously for 170 days. The process achieved self-circulation of 20-32 times and an up-flow velocity within the reactor of 7-16 m/h which were accurately controlled with only separate aeration. The larger proportion of self-circulating multiple times contributed to particle formation and stability, providing hydraulic shear conditions, and screened the precipitation performance of the granular sludge (GS). Meanwhile, the dissolved oxygen (DO) of Zier-O was controlled at 0.1-0.3 mg/L, and the DO of Zier-A input water was zero. The accurate oxygen supply enhanced simultaneous nitrification and denitrification (SND) as well as short-cut nitrification and denitrification in Zier-O and improved the COD utilization rate and the nitrogen removal rate in Zier-A. The COD treatment capacity reached 2.46 kg-COD/(m³·d). With a hydraulic retention time of 10 h, the process consistently ensured that the average concentrations of ammonia nitrogen and total nitrogen in the effluent were maintained below 5 and 15 mg/L, respectively. Moreover, the process maintained the shape and stability of GS, the median diameter of GS ranged between 300-1210 μm, the percentage of mass with particle size distribution < 200 μm at a height of 150 cm within Zier-A and Zier-O accounted for as low as 0.04%-0.05%, and showed good settling performance. The suspended solids in effluent can be maintained at 50-80 mg/L. Overall, the unique structural setting and control method of the Zier process provide another approach for the application of continuous AGS treatment for municipal sewage.
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Affiliation(s)
- Cong Wang
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China; Beijing Drainage Group Co., Ltd., Beijing 100044, China
| | - Wei-Kang Qi
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Shu-Jun 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; Beijing Drainage Group Co., Ltd., Beijing 100044, China
| | - Li-Fang Liu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Yong-Zhen 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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13
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Xing F, Zhang H, Zhao H, Sun B, Wang T, Guo K, Dong K, Gu S, Wang L. Novel insights into intrinsic mechanisms of magnetic field on long-term performance of anaerobic ammonium oxidation process. BIORESOURCE TECHNOLOGY 2024; 402:130839. [PMID: 38744396 DOI: 10.1016/j.biortech.2024.130839] [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: 03/05/2024] [Revised: 05/10/2024] [Accepted: 05/11/2024] [Indexed: 05/16/2024]
Abstract
The performance of an anaerobic ammonium oxidation (anammox) reactor with the magnetic field of 40 mT was systematically investigated. The total nitrogen removal rate was enhanced by 16% compared with that of the control group. The enhancing mechanism was elucidated from the improved mass transfer efficiency, the complicated symbiotic interspecific relationship and the improved levels of functional genes. The magnetic field promoted formation of the loose anammox granular sludge and the homogeneous and well-connected porous structure to enhance the mass transfer. Consequently, Candidatus Brocadia predominated in the sludge with an increase in abundance of 13%. Network analysis showed that the positive interactions between Candidatus Brocadia and heterotrophic bacteria were strengthened, which established a more complicated stable microbial community. Moreover, the magnetic field increased the levels of hdh by 26% and hzs by 35% to promote the nitrogen metabolic process. These results provided novel insights into the magnetic field-enhanced anammox process.
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Affiliation(s)
- Fanghua Xing
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Hui Zhang
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Haishuo Zhao
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Binbin Sun
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Tao Wang
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China.
| | - Kaiyuan Guo
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Kaidi Dong
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Siqi Gu
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
| | - Luyao Wang
- Institute of Pollution Control and Environmental Health, School of Energy and Environmental Engineering, Hebei University of Technology, Tianjin 300401, PR China
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14
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Cao DQ, Jin Y, Liu H, Lei SC, Song YX, Han JL, Hao XD, Ma MG, Zhang Z, Wu R. Concentration properties of biopolymers via dead-end forward osmosis. Int J Biol Macromol 2024; 270:132338. [PMID: 38763237 DOI: 10.1016/j.ijbiomac.2024.132338] [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: 02/11/2024] [Revised: 04/29/2024] [Accepted: 05/11/2024] [Indexed: 05/21/2024]
Abstract
Extracellular polymeric substances (EPSs) in excess sludge of wastewater treatment plants are valuable biopolymers that can act as recovery materials. However, effectively concentrating EPSs consumes a significant amount of energy. This study employed novel energy-saving pressure-free dead-end forward osmosis (DEFO) technology to concentrate various biopolymers, including EPSs and model biopolymers [sodium alginate (SA), bovine serum albumin (BSA), and a mixture of both (denoted as BSA-SA)]. The feasibility of the DEFO technology was proven and the largest concentration ratios for these biopolymers were 94.8 % for EPSs, 97.1 % for SA, 97.8 % for BSA, and 98.4 % for BSA-SA solutions. An evaluation model was proposed, incorporating the FO membrane's water permeability coefficient and the concentrated substances' osmotic resistance, to describe biopolymers' concentration properties. Irrespective of biopolymer type, the water permeability coefficient decreased with increasing osmotic pressure, remained constant with increasing feed solution (FS) concentration, increased with increasing crossing velocity in the draw side, and showed little dependence on draw salt type. In the EPS DEFO concentration process, osmotic resistance was minimally impacted by osmotic pressure, FS concentration, and crossing velocity, and monovalent metal salts were proposed as draw solutes. The interaction between reverse diffusion metal cations and EPSs affected the structure of the concentrated substances on the FO membrane, thus changing the osmotic resistance in the DEFO process. These findings offer insights into the efficient concentration of biopolymers using DEFO.
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Affiliation(s)
- Da-Qi Cao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China; Yau Mathematical Sciences Center, Tsinghua University, Beijing 100084, China.
| | - Yan Jin
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Hui Liu
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Shi-Cheng Lei
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Yi-Xuan Song
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Jia-Lin Han
- Beijing Drainage Group Co. Ltd (BDG), Beijing 100061, China
| | - Xiao-Di Hao
- Sino-Dutch R&D Centre for Future Wastewater Treatment Technologies/Key Laboratory of Urban Stormwater System and Water Environment, Beijing University of Civil Engineering and Architecture, Beijing 100044, China
| | - Ming-Guo Ma
- Research Center of Biomass Clean Utilization, MOE Engineering Research Center of Forestry Biomass Materials and Bioenergy, Beijing Key Laboratory of Lignocellulosic Chemistry, College of Materials Science and Technology, Beijing Forestry University, Beijing 100083, China
| | - Zhongguo Zhang
- National Engineering Laboratory of Circular Economy, Institute of Resources and Environment, Beijing Academy of Science and Technology, Beijing 100095, China
| | - Rongling Wu
- Yau Mathematical Sciences Center, Tsinghua University, Beijing 100084, China; Beijing Institute of Mathematical Sciences and Applications, Beijing 101408, China
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15
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Chen Y, Zhang C, Chen Z, Yang Y, Lin Z, Deng Z, Wang X. Fe(II)-driven spatiotemporal assembly of heterotrophic and anammox bacteria enhances simultaneous nitrogen and phosphorus removal for low-strength municipal wastewater. BIORESOURCE TECHNOLOGY 2024; 401:130713. [PMID: 38641305 DOI: 10.1016/j.biortech.2024.130713] [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: 03/03/2024] [Revised: 04/15/2024] [Accepted: 04/16/2024] [Indexed: 04/21/2024]
Abstract
The mainstream anaerobic ammonium oxidation (anammox) faces considerable challenges with low-strength municipal wastewater. A Fe(Ⅱ)-amended partial denitrification coupled anammox (PD/A) process was conducted and achieved a long-term and efficient nitrogen and phosphorus removal, yielding effluent total nitrogen and phosphorus concentrations of 1.97 ± 1.03 mg/L and 0.23 ± 0.13 mg/L, respectively, which could well meet more stringent effluent discharge standard of some wastewater treatment plants in specific geographical locations, e.g., estuaries. Fe(Ⅱ)-driven vivianite formation provided key nucleuses for the optimization of the spatial distribution of heterotrophic and anammox bacteria with enhanced extracellular polymeric substances as key driving forces. Metagenomics analysis further revealed the increase of key genes, enhancing anammox bacteria homeostasis, which also bolstered the resistance to environmental perturbations. This study provided a comprehensive sight into the function of Fe(Ⅱ) in mainstream PD/A process, and explored a promising alternative for synergetic nitrogen and phosphorus removal for low-strength municipal wastewater treatment.
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Affiliation(s)
- Yongxing Chen
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Chuchu Zhang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Zhenguo Chen
- School of Environment, South China Normal University, Guangzhou 510006, China
| | - Yuchun Yang
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zhiman Lin
- State Key Laboratory of Biocontrol, School of Ecology, Sun Yat-Sen University, Guangzhou 510275, China
| | - Zexi Deng
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China
| | - Xiaojun Wang
- School of Environment and Energy, South China University of Technology, Guangzhou 510006, China; The Key Lab of Pollution Control and Ecosystem Restoration in Industry Clusters, Ministry of Education, China; Hua An Biotech Co., Ltd., Foshan 528300, China.
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16
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Liu Y, Ye X, Chen K, Wu X, Jiao L, Zhang H, Zhu F, Xi Y. Effect of nanobubble water on medium chain carboxylic acids production in anaerobic digestion of cow manure. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 184:37-51. [PMID: 38795539 DOI: 10.1016/j.wasman.2024.05.029] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/19/2024] [Revised: 04/30/2024] [Accepted: 05/20/2024] [Indexed: 05/28/2024]
Abstract
Nanobubble water promotes the degradation of difficult-to-degrade organic matter, improves the activity of electron transfer systems during anaerobic digestion, and optimizes the composition of anaerobic microbial communities. Therefore, this study proposes the use of nanobubble water to improve the yield of medium chain carboxylic acids produced from cow manure by chain elongation. The experiment was divided into two stages: the first stage involved the acidification of cow manure to produce volatile acidic fatty acids as electron acceptors, and the second phase involved the addition of lactic acid as an electron donor for the chain elongation. Three experimental groups were established, and air, H2, and N2 nanobubble water were added in the second stage. Equal amounts of deionized water were added in the control group. The results showed that nanobubble water supplemented with air significantly increased the caproic acid concentration to 15.10 g/L, which was 55.03 % greater than that of the control group. The relative abundances of Bacillus and Caproiciproducens, which are involved in chain elongation, and Syntrophomonas, which is involved in electron transfer, increased. The unique ability of air nanobubble water supplemented to break down the cellulose matrix resulted in further decomposition of the recalcitrant material in cow manure. This effect subsequently increased the number of microorganisms associated with lignocellulose degradation, increasing carbohydrate metabolism and ATP-binding cassette transporter protein activity and enhancing fatty acid cycling pathways during chain elongation. Ultimately, this approach enabled the efficient production of medium chain carboxylic acids.
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Affiliation(s)
- Yang Liu
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China; State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical, Nanjing Tech University, Nanjing 210009, China
| | - Xiaomei Ye
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China
| | - Kequan Chen
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical, Nanjing Tech University, Nanjing 210009, China
| | - Xiayuan Wu
- State Key Laboratory of Materials-Oriented Chemical Engineering, College of Biotechnology and Pharmaceutical, Nanjing Tech University, Nanjing 210009, China
| | - Lihua Jiao
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China
| | - Hongyu Zhang
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China
| | - Fei Zhu
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China
| | - Yonglan Xi
- Jiangsu Academy of Agriculture Sciences, Nanjing 210014, China; Key Laboratory of Crop and Livestock Integration, Ministry of Agriculture and Rural Affairs, Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, 210014 Nanjing, China; Department of Applied Ecology, Faculty of Environmental Sciences, Czech University of Life Sciences Prague, Kamýcka 129, Praha-Suchdol 16500, Czech Republic.
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17
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Wang X, Li Y, Zhang X, Chen X, Wang X, Yu D, Ge B. The extracellular polymeric substances (EPS) accumulation of Spirulina platensis responding to Cadmium (Cd 2+) exposure. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134244. [PMID: 38598879 DOI: 10.1016/j.jhazmat.2024.134244] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2024] [Revised: 04/03/2024] [Accepted: 04/07/2024] [Indexed: 04/12/2024]
Abstract
Spirulina platensis can secrete extracellular polymeric substances (EPS) helping to protect damage from stress environment, such as cadmium (Cd2+) exposure. However, the responding mechanism of S. platensis and the secreted EPS to exposure of Cd2+ is still unclear. This research focuses on the effects of Cd2+ on the composition and structure of the EPS and the response mechanism of EPS secretion from S. platensis for Cd2+ exposure. S. platensis can produce 261.37 mg·g-1 EPS when exposing to 20 mg·L-1 CdCl2, which was 2.5 times higher than the control group. The S. platensis EPS with and without Cd2+ treatment presented similar and stable irregularly fibrous structure. The monosaccharides composition of EPS in Cd2+ treated group are similar with control group but with different monosaccharides molar ratios, especially for Rha, Gal, Glc and Glc-UA. And the Cd2+ treatment resulted in a remarkable decline of humic acid and fulvic acid content. The antioxidant ability of S. platensis EPS increased significantly when exposed to 20 mg·L-1 CdCl2, which could be helpful for S. platensis protecting damage from high concentration of Cd2+. The transcriptome analysis showed that sulfur related metabolic pathways were up-regulated significantly, which promoted the synthesis of sulfur-containing amino acids and the secretion of large amounts of EPS.
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Affiliation(s)
- Xiufeng Wang
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Yuhui Li
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Xiaojing Zhang
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Xin Chen
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Xin Wang
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Daoyong Yu
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China
| | - Baosheng Ge
- State Key Laboratory of Heavy Oil Processing and Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao 266580, PR China.
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18
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Qian X, Huang J, Yan C, Xiao J, Cao C, Wu Y, Wang L. Evaluation of ecological impacts with ferrous iron addition in constructed wetland under perfluorooctanoic acid stress. JOURNAL OF HAZARDOUS MATERIALS 2024; 469:134074. [PMID: 38518702 DOI: 10.1016/j.jhazmat.2024.134074] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/08/2023] [Revised: 02/27/2024] [Accepted: 03/17/2024] [Indexed: 03/24/2024]
Abstract
In this study, ferrous ion (Fe(II)) had the potential to promote ecological functions in constructed wetlands (CWs) under perfluorooctanoic acid (PFOA) stress. Concretely, Fe(II) at 30 mg/L and 20-30 mg/L even led to 11.37% increase of urease and 93.15-243.61% increase of nitrite oxidoreductase respectively compared to the control. Fe(II) promotion was also observed on Nitrosomonas, Nitrospira, Azospira, and Zoogloea by 1.00-6.50 folds, which might result from higher expression of nitrogen fixation and nitrite redox genes. These findings could be explanation for increase of ammonium removal by 7.47-8.75% with Fe(II) addition, and reduction of nitrate accumulation with 30 mg/L Fe(II). Meanwhile, both Fe(II) stimulation on PAOs like Dechloromonas, Rhodococcus, Mesorhizobium, and Methylobacterium by 1.58-2.00 folds, and improvement on chemical phosphorus removal contributed to higher total phosphorus removal efficiency under high-level PFOA exposure. Moreover, Fe(II) raised chlorophyll content and reduced the oxidative damage brought by PFOA, especially at lower dosage. Nevertheless, combination of Fe(II) and high-level PFOA caused inhibition on microbial alpha diversity, which could result in decline of PFOA removal (by 4.29-12.83%). Besides, decrease of genes related to nitrate reduction demonstrated that enhancement on denitrification was due to nitrite reduction to N2 pathways rather than the first step of denitrifying process.
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Affiliation(s)
- Xiuwen Qian
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China
| | - Juan Huang
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China.
| | - Chunni Yan
- School of Urban Planning and Municipal Engineering, Xi'an Polytechnic University, Xi'an 710048, China
| | - Jun Xiao
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Chong Cao
- Department of Municipal Engineering, College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China
| | - Yufeng Wu
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China
| | - Luming Wang
- Department of Municipal Engineering, School of Civil Engineering, Southeast University, Nanjing 211189, China
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19
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Jiao T, Zhao C, Zhang M, Han F, Liu Z, Zhang S, Zhou W. Recovery mechanism of heterotrophic ammonia assimilation system under chromium hexavalent stress. BIORESOURCE TECHNOLOGY 2024; 399:130615. [PMID: 38513926 DOI: 10.1016/j.biortech.2024.130615] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2024] [Revised: 03/16/2024] [Accepted: 03/18/2024] [Indexed: 03/23/2024]
Abstract
Heterotrophic ammonia assimilation (HAA), an innovative technology for high-salinity wastewater treatment, demonstrates self-recovery capability following Cr (VI) stress. This study investigated the inhibitory effects and self-restoration mechanisms of Cr (VI) at various stress levels. The removal efficiencies of NH4+-N and Cr (VI) in the HAA gradually decreased with increasing influent Cr (VI) concentration. Exposure to Cr (VI) increased the amounts of high-molecular-weight proteins in soluble microbial products and stimulated the generation of extracellular polymeric substances. Heterotrophic functional microorganisms with Cr (VI) tolerance, such as Marinobacter and Planktosalinus, were enriched. An assimilation pathway gene (glnA) and a Cr (VI)-related gene (atoB) were also upregulated. After ceasing Cr (VI) addition, the HAA system demonstrated a 17.1 % increase in the removal efficiency of NH4+-N, which was attributable to its self-recovery ability. This study provides a scientific and theoretical foundation for the HAA process in resisting the impact of heavy-metal-containing wastewater and self-recovery.
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Affiliation(s)
- Tong Jiao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Chuanfu Zhao
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Mengru Zhang
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Fei Han
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Zhe Liu
- Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China; School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, PR China
| | - Shuhui Zhang
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China
| | - Weizhi Zhou
- School of Civil Engineering, Shandong University, Jinan, Shandong, PR China; Laboratory of Water-sediment Regulation and Eco-decontamination, Jinan, Shandong, PR China.
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20
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He S, Zhao L, Feng L, Zhao W, Liu Y, Hu T, Li J, Zhao Q, Wei L, You S. Mechanistic insight into the aggregation ability of anammox microorganisms: Roles of polarity, composition and molecular structure of extracellular polymeric substances. WATER RESEARCH 2024; 254:121438. [PMID: 38467096 DOI: 10.1016/j.watres.2024.121438] [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: 10/22/2023] [Revised: 01/25/2024] [Accepted: 03/06/2024] [Indexed: 03/13/2024]
Abstract
The chemical characteristics of extracellular polymeric substances (EPS) of anammox bacteria (AnAOB) play a crucial role in the rapid enrichment of AnAOB and the stable operation of wastewater anammox processes. To clarify the influential mechanisms of sludge EPS on AnAOB aggregation, multiple parameters, including the polarity distribution, composition, and molecular structure of EPS, were selected, and their quantitative relationship with AnAOB aggregation was analyzed. Compared to typical anaerobic sludge (anaerobic floc and granular sludge), the anammox sludge EPS exhibited higher levels of tryptophan-like substances (44.82-56.52 % vs. 2.57-39.81 %), polysaccharides (40.02-53.49 mg/g VSS vs. 30.22-41.69 mg/g VSS), and protein structural units including α-helices (20.70-23.98 % vs. 16.48-19.32 %), β-sheets (37.43-42.98 % vs. 25.78-36.72 %), and protonated nitrogen (Npr) (0.065-0.122 vs. 0.017-0.061). In contrast, it had lower contents of β-turns (20.95-27.39 % vs. 28.17-39.04 %). These biopolymers were found to originate from different genera of AnAOB. Specifically, the α-helix-rich proteins were mainly derived from Candidatus Kuenenia, whereas the extracellular proteins related to tryptophan and Npr were closely associated with Candidatus Brocadia. Critically, these EPS components could drive anammox aggregation through interactions. Substantial amounts of tryptophan-like substances facilitated the formation of β-sheet structures and the exposure of internal hydrophobic clusters, which benefited the anammox aggregation. Meanwhile, extracellular proteins with high Npr content played a pivotal role in the formation of mixed protein-polysaccharide gel networks with the electronegative regions of polysaccharides, which could be regarded as the key component in the maintenance of anammox sludge stability. These findings provide a comprehensive understanding of the multifaceted roles of EPS in driving anammox aggregation and offer valuable insights into the development of EPS regulation strategies aimed at optimizing the anammox process.
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Affiliation(s)
- Shufei He
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Lingxin Zhao
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Likui Feng
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Weixin Zhao
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Yu Liu
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Tianyi Hu
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Jianju Li
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Qingliang Zhao
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
| | - Liangliang Wei
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Shijie You
- State Key Laboratory of Urban Water Resources and Environment (SKLUWRE), School of Environment, Harbin Institute of Technology, Harbin 150090, China
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21
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Li C, Zhang Y, Ren J, Mo Z, Liang J, Ye M, Ou W, Sun S, Zhu S. In-situ generation of iron activated percarbonate for sustainable sludge dewatering. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 922:171235. [PMID: 38417502 DOI: 10.1016/j.scitotenv.2024.171235] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/03/2024] [Revised: 02/12/2024] [Accepted: 02/22/2024] [Indexed: 03/01/2024]
Abstract
Effective dewatering of sewage sludge could potentially address the issues of high energy consumption and large carbon footprint inherent in the sludge treatment process, advancing toward carbon neutrality in environmental remediation. Yet, the surface hydrophilic characteristics and water-holding interfacial affinity in sludge led to dwindled sludge-water separation performance. Here, the integration of in-situ generation of iron from zero-valent scrap iron (ZVSI) and sodium percarbonate (SPC) was attempted to attenuate the water-retaining interfacial affinity within sludge, thus achieving superior sludge dewatering performance. Results showed that under the optimal conditions, the ZVSI + SPC system led to a remarkable decline of 76.09 % in the specific resistance to filtration of the sludge, accompanied by a notable decline of 34.96 % in the water content. Moreover, the utilization of ZVSI + SPC system could be a viable alternative to the traditional strategies in terms of enhanced sludge dewaterability, offering application potential with stable operating performance, economic feasibility, and reduced carbon emissions. Investigation into dewatering mechanism revealed that ZVSI could maintain the Fe3+/Fe2+ in a stable dynamic cycle and continuously in-situ generate Fe2+, thereby efficaciously fostering the SPC activation for the ceaseless yield of reactive oxygen species. The predominant •OH and 1O2 efficiently decomposed the hydrophilic biopolymers, therefore minimizing the hydrophilic protein secondary structures, along with the hydrogen and disulfide bonds within proteins. Subsequently, the water-holding interfacial affinity was profoundly diminished, leading to intensified hydrophobicity, self-flocculation, and dewaterability. These findings have important implications for the advancement of efficacious ZVSI + SPC conditioning techniques toward sustainable energy and low-carbon prospects.
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Affiliation(s)
- Chengjian Li
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Yu Zhang
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Jingsai Ren
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Zhihua Mo
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Jialin Liang
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China.
| | - Maoyou Ye
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Wenzhi Ou
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
| | - Shuiyu Sun
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China
| | - Suiyi Zhu
- College of Resources and Environment, Zhongkai University of Agriculture and Engineering, Guangzhou 510225, China
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22
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Cheng M, Fu HM, Mao Z, Yan P, Weng X, Ma TF, Xu XW, Guo JS, Fang F, Chen YP. Motility behavior and physiological response mechanisms of aerobic denitrifier, Enterobacter cloacae strain HNR under high salt stress: Insights from individual cells to populations. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 914:170002. [PMID: 38220024 DOI: 10.1016/j.scitotenv.2024.170002] [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: 10/23/2023] [Revised: 12/20/2023] [Accepted: 01/06/2024] [Indexed: 01/16/2024]
Abstract
The motility behaviors at the individual-cell level and the collective physiological responsive behaviors of aerobic denitrifier, Enterobacter cloacae strain HNR under high salt stress were investigated. The results revealed that as salinity increased, electron transport activity and adenosine triphosphate content decreased from 15.75 μg O2/g/min and 593.51 mM/L to 3.27 μg O2/g/min and 5.34 mM/L, respectively, at 40 g/L, leading to a reduction in the rotation velocity and vibration amplitude of strain HNR. High salinity stress (40 g/L) down-regulated genes involved in ABC transporters (amino acids, sugars, metal ions, and inorganic ions) and activated the biofilm-related motility regulation mechanism in strain HNR, resulting in a further decrease in flagellar motility capacity and an increase in extracellular polymeric substances secretion (4.08 mg/g cell of PS and 40.03 mg/g cell of PN at 40 g/L). These responses facilitated biofilm formation and proved effective in countering elevated salt stress in strain HNR. Moreover, the genetic diversity associated with biofilm-related motility regulation in strain HNR enhanced the adaptability and stability of the strain HNR populations to salinity stress. This study enables a deeper understanding of the response mechanism of aerobic denitrifiers to high salt stress.
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Affiliation(s)
- Meng Cheng
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Hui-Min Fu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing 400067, China
| | - Zheng Mao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; Chongqing Institute of Geology and Mineral Resources, Chongqing 400042, China
| | - Peng Yan
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Xun Weng
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Teng-Fei Ma
- National Research Base of Intelligent Manufacturing Service, Chongqing Technology and Business University, Chongqing 400067, China
| | - Xiao-Wei Xu
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Jin-Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - Fang Fang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China
| | - You-Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China.
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23
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Wang H, Xu H, Liu X, Hua Y, Yang D, Dai X. A novel process based on powder carriers demonstrates robustness in nitrogen and phosphorus removal from real municipal wastewater. WATER RESEARCH 2024; 251:121149. [PMID: 38237462 DOI: 10.1016/j.watres.2024.121149] [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: 12/05/2023] [Revised: 01/05/2024] [Accepted: 01/15/2024] [Indexed: 02/12/2024]
Abstract
The development of efficient and low-consumption wastewater upgrading process is currently at the forefront of the wastewater treatment field. In this study, a novel wastewater treatment process based on powder carriers was proposed. Three systems, namely the activated sludge (AS) system, powder carrier (PC) system, and moving bed biofilm reactor (MBBR) system, were established and operated for over 140 days to treat real municipal wastewater. The characteristics and differences between the three systems were comprehensively investigated. The results suggested that the PC system exhibited notable advantages in nitrogen and phosphorus removal, especially under high influent load and low aeration conditions. The PC system, characterized by a higher nitrification rate compared to the MBBR system and a higher denitrification rate compared to the AS system, contributed to the stable nitrogen removal performance. The particle size of the zoogloea increased under the linkage of the powder carriers, and the mean size of micro-granules reached 170.88 μm. Large number of hydrophobic functional groups on sludge surface, coupled with increased protein content in EPS, further promoted sludge aggregation. Micro-granules formation improved settling performance and enhanced the abundance and activity of functional microbes. A significant enrichment in denitrifying bacteria and denitrifying phosphorus accumulating bacteria was observed in PC system. Up-regulation of the napA, narG, and nosZ genes was responsible for efficient nitrogen removal of the PC system. Moreover, a higher abundance in polyphosphate phosphotransferase (2.11 %) was found in PC system compared with AS and MBBR systems. The increase in the enzymes associated with poly-β-hydroxybutyrate (PHB) synthesis metabolism in PC system provided the energy for denitrification and phosphorus removal processes.
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Affiliation(s)
- Hong Wang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Haolian Xu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Xiaoguang Liu
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
| | - Yu Hua
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Donghai Yang
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China
| | - Xiaohu Dai
- State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, 1239 Siping Road, Shanghai 200092, China.
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24
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Li S, Duan G, Xi Y, Chu Y, Li F, Ho SH. Insights into the role of extracellular polymeric substances (EPS) in the spread of antibiotic resistance genes. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2024; 343:123285. [PMID: 38169168 DOI: 10.1016/j.envpol.2023.123285] [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: 08/21/2023] [Revised: 11/28/2023] [Accepted: 12/30/2023] [Indexed: 01/05/2024]
Abstract
Antibiotic resistance genes (ARG) are prevalent in aquatic environments. Discharge from wastewater treatment plants is an important point source of ARG release into the environment. It has been reported that biological treatment processes may enhance rather than remove ARG because of their presence in sludge. Attenuation of ARG in biotechnological processes has been studied in depth, showing that many microorganisms can secrete complex extracellular polymeric substances (EPS). These EPS can serve as multifunctional elements of microbial communities, involving aspects, such as protection, structure, recognition, adhesion, and physiology. These aspects can influence the interaction between microbial cells and extracellular ARG, as well as the uptake of extracellular ARG by microbial cells, thus changing the transformative capability of extracellular ARG. However, it remains unclear whether EPS can affect horizontal ARG transfer, which is one of the main processes of ARG dissemination. In light of this knowledge gap, this review provides insight into the role of EPS in the transmission of ARGs; furthermore, the mechanism of ARG spread is analyzed, and the molecular compositions and functional properties of EPS are summarized; also, how EPS influence ARG mitigation is addressed, and factors impacting how EPS facilitate ARG during wastewater treatment are summarized. This review provides comprehensive insights into the role of EPS in controlling the transport and fate of ARG during biodegradation processes at the mechanistic level.
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Affiliation(s)
- Shengnan Li
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province, 150090, China
| | - Guoxiang Duan
- Heilongjiang Academy of Chinese Medical Sciences, Harbin, China
| | - Yucan Xi
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province, 150090, China
| | - Yuhao Chu
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province, 150090, China
| | - Fengxiang Li
- Key Laboratory of Pollution Processes and Environmental Criteria at Ministry of Education, Tianjin Key Laboratory of Environmental Remediation and Pollution Control, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Shih-Hsin Ho
- State Key Laboratory of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, Heilongjiang Province, 150090, China.
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25
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You F, Tang M, Zhang J, Wang D, Fu Q, Zheng J, Ye B, Zhou Y, Li X, Yang Q, Liu X, Duan A, Liu J. Benzethonium chloride affects short chain fatty acids produced from anaerobic fermentation of waste activated sludge: Performance, biodegradation and mechanisms. WATER RESEARCH 2024; 250:121024. [PMID: 38113597 DOI: 10.1016/j.watres.2023.121024] [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: 09/01/2023] [Revised: 11/17/2023] [Accepted: 12/14/2023] [Indexed: 12/21/2023]
Abstract
Benzethonium chloride (BZC) is viewed as a promising disinfectant and widely applied in daily life. While studies related to its effect on waste activated sludge (WAS) anaerobic fermentation (AF) were seldom mentioned before. To understand how BZC affects AF of WAS, production of short chain fatty acids (SCFAs), characteristics of WAS as well as microbial community were evaluated during AF. Results manifested a dose-specific relationship of dosages between BZC and SCFAs and the optimum yield arrived at 2441.01 mg COD/L with the addition of 0.030 g/g TSS BZC. Spectral results and protein secondary structure variation indicated that BZC denatured proteins in the solid phase into smaller proteins or amino acids with unstable structures. It was also found that BZC could stimulate the extracellular polymeric substances secretion and reduce the surface tension of WAS, leading to the enhancement of solubilization. Beside, BZC promoted the hydrolysis stage (increased by 7.09 % to 0.030 g/g TSS BZC), but inhibited acetogenesis and methanogenesis stages (decreased by 6.85 % and 14.75 % to 0.030 g/g TSS BZC). The microbial community was also regulated by BZC to facilitate the enrichment of hydrolytic and acidizing microorganisms (i.e. Firmicutes). All these variations caused by BZC were conducive to the accumulation of SCFAs. The findings contributed to investigating the effect of BZC on AF of WAS and provided a new idea for the future study of AF mechanism.
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Affiliation(s)
- Fengyuan You
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Mengge Tang
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Jiamin Zhang
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Dongbo Wang
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Qizi Fu
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Jiangfu Zheng
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Boqun Ye
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Yintong Zhou
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Xiaoming Li
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China.
| | - Qi Yang
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Xuran Liu
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Abing Duan
- Hunan University and Key Laboratory of Environmental Biology and Pollution Control (Hunan University), College of Environmental Science and Engineering, Ministry of Education, Changsha 410082, PR China
| | - Junwu Liu
- Hunan Engineering Research Center of Mining Site Pollution Remediation, Changsha 410082, PR China
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26
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Guo X, Tang X, Zhang M, Ma X, Wang J, Liang H. New progress in the deep understanding of the biocake layer property: Combined effect of neglected protein secondary structure, morphology, and mechanism. WATER RESEARCH 2024; 250:121038. [PMID: 38157600 DOI: 10.1016/j.watres.2023.121038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/28/2023] [Revised: 12/02/2023] [Accepted: 12/18/2023] [Indexed: 01/03/2024]
Abstract
The application of magnetic fields (MFs) and magnetic particles (MPs) in water treatment has attracted widespread attention due to their stability, strong biological compatibility, and less chemical consumption. This study introduced MPs and MFs to GDM and probed their effects on filtration performance. Predeposited large MPs (P-large) and batch-added little MPs (B-little) intervened biocake layer development, forming more open and porous structures, they also reduced biomass secretion, resulting in flux increases of 13 % in P-large and 40 % in B-little than P-little, respectively. Besides, MFs controlled MPs distribution on the biocake layer, resulting in forming of more rough and open structures. A relatively lower magnetic field of 20 mT facilitated biomass secretion, while a higher magnetic field of 50 mT decreased biomass. Furthermore, applying magnetic fields decreased the ratios of α-helix and β-sheet, and increased random coil percentage. Thus, applying magnetic field mediation would contribute to the flux improvements in I-20 and I-50 by 29 % and 32 % relative to I-0. Economic analysis suggested introducing MPs and MFs to GDM was economically feasible, synergy of MPs and MFs had more economic advantages on the community scale and MPs-assisted GDM had significant economic advantages on both community and household scales. Future works should focus on developing new technologies for the recycling of MPs and membranes. This study provided new insight into the protein secondary structures associated with GDM performance and would encourage new sustainable MFs and MPs-assisted GDM technological developments.
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Affiliation(s)
- Xishou Guo
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Xiaobin Tang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China.
| | - Meng Zhang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Xiaobin Ma
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, PR China
| | - Jinlong Wang
- State Key Laboratory of Urban Water Resource and Environment (SKLUWRE), Harbin Institute of Technology, 73 Huanghe Road, Nangang District, Harbin 150090, 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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27
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Zhang Z, Liu R, Lan Y, Zheng W, Chen L. Anaerobic co-fermentation of waste activated sludge with corn gluten meal enhanced phosphorus release and volatile fatty acids production: Critical role of corn gluten meal dosage on fermentation stages and microbial community traits. BIORESOURCE TECHNOLOGY 2024; 394:130275. [PMID: 38176597 DOI: 10.1016/j.biortech.2023.130275] [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: 10/25/2023] [Revised: 12/26/2023] [Accepted: 12/28/2023] [Indexed: 01/06/2024]
Abstract
The anaerobic co-fermentation of iron bound phosphorus (P) compounds (FePs)-bearing sludge with corn gluten meal (CGM) and the underlying mechanisms associated with P release and volatile fatty acids (VFAs) production were investigated. The optimal CGM dosage for P release was 0.6 g chemical oxygen demand (COD)/g total suspended solid (TSS), which resulted in an increase in efficiency from 7 % (control sample) to 39 %. However, the optimal CGM dosage for VFAs production was 0.4 g COD/g TSS, and the yield increased from 37.4 (control sample) to 331.7 mg COD/g volatile suspended solid. The addition of CGM enhanced hydrolysis and acidogenesis by supplying abundant organic substrates to promote the growth of hydrolytic and acidogenic bacteria. A higher VFAs/ammonium-nitrogen ratio resulted in a lower pH, which promoted greater FePs dissolution and P release from the sludge. This study provides novel insights into the effects of CGM on P release and VFAs production.
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Affiliation(s)
- Zhipeng Zhang
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China; State Key Laboratory of Pollution Control and Resource Reuse, College of Environmental Science and Engineering, Tongji University, Shanghai 200092, China
| | - Rui Liu
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China.
| | - Yaqiong Lan
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China
| | - Wei Zheng
- Zhejiang Provincial Key Laboratory of Water Science and Technology, Department of Environment, Yangtze Delta Region Institute of Tsinghua University, Zhejiang, Jiaxing 314006, China
| | - Lujun Chen
- School of Environment, Tsinghua University, Beijing 100084, China
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Li M, Han F, Zhang Z, Zeng H, Li D, Zhang J. Effect of 2,4-dichlorophenol on the production of methane from anaerobic granular sludge during anaerobic digestion through spectroscopy analysis. ENVIRONMENTAL TECHNOLOGY 2024; 45:916-925. [PMID: 36172646 DOI: 10.1080/09593330.2022.2130107] [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: 06/27/2022] [Accepted: 09/12/2022] [Indexed: 06/16/2023]
Abstract
Chlorophenols in urban high organic wastewater increases, which plays an inhibitory role in the process of anaerobic fermentation and methanogenesis. The release rules of extracellular polymers (EPS) and soluble microbial products (SMP) and the production of methane from anaerobic granular sludge were evaluated by spectroscopic analysis. The methane production was reduced by 21.6%, 41.4% and 50.5% respectively by adding 2,4-DCP of different concentrations (25, 50 and 100 mg/L). Activity tests of methanogenic functional enzymes indicated that F420 was more susceptible to the toxic of 2, 4-DCP than Acetyl-CoA and NADH. The decrease in methane production was due to the reduction in the activity of conversion enzymes rather than the loss of crucial precursors for methanogenesis. 2,4-DCP disintegrated the protein 'shell' of anaerobic granular sludge by destroying α-helix and β-sheet structures. After the protein 'shell' in EPS was destroyed, 2, 4-DCP entered the interior of granular, which inhibited the activity of functional enzymes and affected the process of acidogenesis and methanogenesis. At the same time, due to the partial rupture of the cells after being affected by the toxicity of 2,4-DCP, the protein material could be dissolved into the aqueous phase and complexed with 2,4-DCP to reduce the toxic effect of 2,4-DCP.
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Affiliation(s)
- Mingrun Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Fei Han
- School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong, People's Republic of China
| | - Zhaoran Zhang
- Jinan Environmental Research Academy, Jinan, People's Republic of China
| | - Huiping Zeng
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Dong Li
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, People's Republic of China
| | - Jie Zhang
- Key Laboratory of Water Science and Water Environment Recovery Engineering, Beijing University of Technology, Beijing, People's Republic of China
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, People's Republic of China
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Zhang J, Li X, Du R, Li X, Zhang Q, Peng Y. Rapid formation of denitrification granules for nitrite accumulation by increasing nitrogen loading rates and resistance to industrial wastewater. BIORESOURCE TECHNOLOGY 2024; 394:130238. [PMID: 38142908 DOI: 10.1016/j.biortech.2023.130238] [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: 10/02/2023] [Revised: 12/19/2023] [Accepted: 12/19/2023] [Indexed: 12/26/2023]
Abstract
The nitrite (NO2-) accumulation in partial denitrification (PD) offers the possibility of widespread application of anammox process. In this study, the rapid establishment of PD granular system was achieved by increasing nitrogen loading rates (NLR) from 0.9 to 4.8 kg N/(m3·d), with the nitrate-to-nitrite transforming ratio (NTR) increasing rapidly to 87.0 % within 18 days. Growth evidence indicated that the functional genus Thauera was significantly enriched (12.5 %→76.4 %), with nitrate (NO3-) reduction rates (SNO3) improving by 5.4 times from 13.0 to 70.7 mg N/(g VSS·h). Importantly, the rapid aggregation of PD biomass as granules ensured robustness and resistance of PD feeding with the electroplating tail wastewater (NO3--N of 103.0 ± 5.0 mg/L), obtaining stable NTR above 91.5 %. This study demonstrated the achievability of the fast development of PD granules and the adaptability and robustness of treating nitrate-containing industrial wastewater, which provided a promising method for efficient nitrogen transformation in industrial applications.
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Affiliation(s)
- Jingwen 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
| | - Xiyao 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
| | - Rui Du
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Engineering Research Center of Beijing, Beijing University of Technology, Beijing 100124, PR China
| | - Xiangchen 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
| | - 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
| | - 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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30
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Xu M, Zhu F, Yang Y, Liu M, Li X, Jiang Y, Feng L, Duan J, Wang W, Yuan X, Zhang X. Mechanism of transport and toxicity response of Chlorella sorokiniana to polystyrene nanoplastics. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2024; 270:115901. [PMID: 38157799 DOI: 10.1016/j.ecoenv.2023.115901] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/01/2023] [Revised: 12/18/2023] [Accepted: 12/26/2023] [Indexed: 01/03/2024]
Abstract
The toxicity of nanoparticles to freshwater microalgae is of significant importance in maintaining the overall stability of aquatic ecosystems. However, the transport mechanism and toxicity response of microalgae towards nanoplastics (NPs) remain to be further investigated. In this study, we examined the toxicity and internalization mechanisms of polystyrene nanoplastics (PS-NPs) in the microalga Chlorella sorokiniana. The results revealed that the PS-NPs inhibited algal cells' growth and disrupted cell integrity upon contact, leading to cell shrinkage or rupture. Moreover, amino-modified PS-NPs (Nano-PS-NH2) exhibited greater toxicity to C. sorokiniana than carboxyl-modified PS-NPs (Nano-PS-COOH). Furthermore, significant inhibition of PS-NPs internalization was observed when four different endocytosis-related inhibitors were used, indicating that internalized PS-NPs can enter algal cells through endocytic pathways. More importantly, C. sorokiniana exposed to Nano-PS-NH2 responded to the reduction in carbon sources and energy resulting from the suppression of photosynthesis by regulating the metabolism of carbohydrates. These findings elucidate the effects of PS-NPs on C. sorokiniana, including their impact on cell morphology and metabolism, while shedding light on the internalization mechanisms of NPs by C. sorokiniana which deepen our understanding of the toxicity of nanoplastics on algae and provide important theoretical support for solving such aquatic ecological environment problems.
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Affiliation(s)
- Mengxin Xu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Fanping Zhu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Yueyao Yang
- School of Environment, Hangzhou Institute for Advanced Study, UCAS, Hangzhou, Zhejiang 310024, PR China
| | - Meiyan Liu
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Xiaohua Li
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Yuqian Jiang
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Lijuan Feng
- College of Geography and Environment, Shandong Normal University, Jinan, Shandong 250014, PR China
| | - Jianlu Duan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China
| | - Weijia Wang
- School of Cyber Science and Technology, Shandong University, Qingdao, Shandong 266237, PR China
| | - Xianzheng Yuan
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China; Sino-French Research Institute for Ecology and Environment (ISFREE), Shandong University, Qingdao, Shandong 266237, PR China
| | - Xiaohan Zhang
- Shandong Key Laboratory of Environmental Processes and Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, PR China.
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Yang G, Wei L, Wang X, Wu X, He Y, Li G, Chen T, Zhu W. Enhancing Commercially Iron Powder Electron Transport by Surface Biosulfuration to Achieve Uranium Extraction from Uranium Ore Wastewater. Inorg Chem 2024; 63:1378-1387. [PMID: 38164710 DOI: 10.1021/acs.inorgchem.3c03906] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2024]
Abstract
The zero-valent iron (ZVI) has attracted increasing attention due to the enhanced reactivity of ZVI to uranium wastewater. However, ZVI practical application is hampered due to its susceptibility to oxidation and the formation of passivation layers during storage and in situ restoration. To address these issues, we used a biosulfuration approach to modify ZVI for application in uranium ore wastewater treatment. A series of physicochemical characterization tools and photoelectronic analyses showed that BS-ZVI considerably increased carrier separation efficiency and visible light absorption capacity, resulting in a significant photoassisted enhancement effect on uranium extraction. Accordingly, the uranium removal efficiency of BS-ZVI reached 91% within 60 min, and its maximum adsorption capacity was 336.3 mg/g. By analyzing the mechanism, the improved U(VI) removal performance was mostly responsible on the dissolution of the passivation layer on the surface of ZVI, the generation of Fe(II) and FeS, and the important role of Shewanella putrefaciens extracellular polymers (EPS). Overall, the BS-ZVI biohybrid merges with the high activity of ZVI, bio-FeS, and self-regeneration ability of bacteria, expanding a promising new approach for sustainable treatment of uranium mine wastewater.
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Affiliation(s)
- Guolin Yang
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
- Laboratory Animal Centre, North Sichuan Medical College, Nanchong, Sichuan 637100, P. R. China
| | - Ling Wei
- Department of Agricultural Science and Technology, Nanchong Vocation and Technical College, Nanchong, Sichuan 637131, P. R. China
| | - Xin Wang
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
| | - Xudong Wu
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
| | - Yizhou He
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
| | - Guo Li
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
| | - Tao Chen
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
| | - Wenkun Zhu
- State Key Laboratory of Environment-friendly Energy Materials, National Co-innovation Center for Nuclear Waste Disposal and Environmental Safety, Sichuan Civil-military Integration Institute, School of Life Science and Engineering, Southwest University of Science and Technology, Mianyang, Sichuan 621010, P. R. China
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32
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Cui Y, Gao J, Zeng L, Guo Y, Xu H, Zhao M. Different fates of extracellular and intracellular antibiotic resistance genes in flocs, granular and biofilm nitrification systems under the stress of acetaminophen. JOURNAL OF HAZARDOUS MATERIALS 2024; 461:132675. [PMID: 37806259 DOI: 10.1016/j.jhazmat.2023.132675] [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: 08/08/2023] [Revised: 09/12/2023] [Accepted: 09/28/2023] [Indexed: 10/10/2023]
Abstract
The spread of antibiotic resistance genes (ARGs), including intracellular ARGs (i-ARGs) and extracellular ARGs (e-ARGs), has become a global problem that cannot be ignored. This study clarified the fates of e-ARGs and i-ARGs in floc sludge reactor (FS), granular sludge reactor (GS) and biofilm reactor (BF) under the stress of acetaminophen (APAP). The results showed that the risk of ARGs transmission, especially for e-ARGs, in FS and BF could increase with the increasing times of APAP treatment, except for that in GS. The fates of i-ARGs in three different systems were similar, which were mainly clustered as the efflux pumps mechanism. The secretion and disintegration of extracellular polymeric substances mainly affected the fates of e-ARGs. In the three systems, the complexity of network relationships between ARGs and microbial communities was FS, GS and BF. Partial least-squares path model analysis indicated that bacterial community directly contributed to the variations of e-ARGs and i-ARGs under APAP treatment in the three systems, playing a leading role. And i-ARGs and protein secondary structure showed direct effects on e-ARGs. This study indicated that e-ARGs in complex systems were more susceptible to be influenced, which should be paid more attention to prevent further propagation of ARGs.
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Affiliation(s)
- Yingchao Cui
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Jingfeng Gao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China.
| | - Liqin Zeng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Yi Guo
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Hongxin Xu
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
| | - Mingyan Zhao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Faculty of Environment and Life, Beijing University of Technology, Beijing 100124, China
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Chen R, Xiao T, Dai X, Dong B. Roles of extracellular polymeric substances in the adsorption and removal of norfloxacin during hydrothermal treatment of sewage sludge. WATER RESEARCH 2024; 248:120899. [PMID: 38000225 DOI: 10.1016/j.watres.2023.120899] [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: 08/26/2023] [Revised: 11/17/2023] [Accepted: 11/18/2023] [Indexed: 11/26/2023]
Abstract
Hydrothermal treatment (HT) is promising to remove antimicrobials from sewage sludge (SS); however, the mechanism of antimicrobial degradation during the HT of SS is not fully understood. In this study, the roles of extracellular polymeric substances (EPS) in the removal and transformation of norfloxacin (NOR) during the HT of SS at temperatures of 100 and 160 °C were investigated. The results indicated that the degradation of NOR increased with increasing HT temperature, with maximum NOR removal (52%) achieved at 160 °C. Furthermore, the NOR in sludge showed higher degradation efficiencies than the control as HT temperature was higher than 120 °C. Evident promotion effects of bound-EPS (B-EPS) in sludge were observed on the NOR degradation as HT temperature was higher than 120 °C, leading to the mineralization and deamination of protein-like components in EPS during HT. Beside, the adsorption capacity of NOR during the HT of SS decreased at temperatures higher than 120 °C. The evolution of the spatial structure of B-EPS was predominantly responsible for the adsorption of antimicrobials, a spontaneous process driven mainly by hydrophilic interactions. With the hydrothermal conversion of B-EPS, the electron transfer, and reactive species (3EPS* and ·OH) derived from B-EPS could facilitate the degradation of NOR. In particular, hydrogen bonds between B-EPS and NOR increased the apparent yield of ·OH and accelerated the decarboxylation of NOR during HT at temperatures higher than 120 °C. A toxicity evaluation suggested that HT for NOR degradation could attenuate toxicity, whereas deep oxidation or mineralization would be needed to promote ecosystem safety. These findings provide new insights into the hydrothermal activation of EPS and the interrelated hydrothermal fate of antimicrobials and other toxic pollutants in sludge.
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Affiliation(s)
- Renjie Chen
- School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Tingting Xiao
- School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China
| | - Xiaohu Dai
- School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China
| | - Bin Dong
- School of Environmental Science and Engineering, Tongji University, Shanghai 200092, PR China; Shanghai Institute of Pollution Control and Ecological Security, Shanghai 200092, PR China; YANGTZE Eco-Environment Engineering Research Center, China Three Gorges Corporation, Beijing 100038, PR China.
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Li H, Wu J, Huang Q, Lin L, Yuan B, Wang Q, Lu H, Liu J, Hong H, Yan C. Combined use of positive matrix factorization and 13C 15N stable isotopes to trace organic matter-bound potential toxic metals in the urban mangrove sediments. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 904:166684. [PMID: 37652389 DOI: 10.1016/j.scitotenv.2023.166684] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/19/2023] [Revised: 08/25/2023] [Accepted: 08/28/2023] [Indexed: 09/02/2023]
Abstract
Coastal sediments act as sinks of sediment organic matter (SOM) and metals because of their special land-sea location and depositional properties. However, there are few reports on the correlation between the sources of organic matter (OM) and associated potential toxic metals (PTMs). In this study, we combined CN stable isotope analysis and positive matrix factorization to identify the matter and metal sources of OM and glomalin-related soil protein (GRSP) in an estuary under several decades of urbanization. The results of the positive matrix factorization (PMF) reveal a correlation between the sources of total sediment metals and the sources of OM-related metals. The sources of both SOM-bound PTMs and GRSP-bound PTMs are significantly related to the sources of total PTMs. OM sources were elucidated through 13C-15 N stable isotopes, and the potential sources of different types of OM differed. In addition, there is a significant correlation between OM-associated PTMs and organic matter sources. Interestingly, the functional groups of SOM were mainly influenced by multiple PTM sources but no OM source, while the functional groups of GRSP were regulated by a single metal source and OM source. This study deepened the understanding of the coupling between PTMs and SOM. The possibility of combined use of positive matrix factorization and 13C-15 N stable isotope tracing of metals as well as the sources of each metal fractions has been evaluated, which will provide new insights for the transportation of PTMs.
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Affiliation(s)
- Hanyi Li
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Jiajia Wu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Qian Huang
- Institute of Geosciences, University of Mainz, Johann-Joachim-Becher-Weg 21, Mainz 55128, Germany.
| | - Lujian Lin
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Bo Yuan
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Qiang Wang
- State Key Laboratory of Grassland Agro-ecosystems, College of Pastoral Agricultural Science and Technology, Lanzhou University, Lanzhou 730020, China.
| | - Haoliang Lu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Jingchun Liu
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Hualong Hong
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
| | - Chonglin Yan
- Key Laboratory of the Ministry of Education for Coastal and Wetland Ecosystems, Xiamen University, Xiamen 361102, China.
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Wang S, Chen H. Enhanced dewaterability of sewage sludge by grafted cationic lignin-based flocculants. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166958. [PMID: 37696410 DOI: 10.1016/j.scitotenv.2023.166958] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/21/2023] [Revised: 09/07/2023] [Accepted: 09/08/2023] [Indexed: 09/13/2023]
Abstract
Lignin-based flocculants are widely used for wastewater purification, but their application in sludge dewatering has not yet been documented. In this study, a novel cationic lignin-based flocculant named LS-g-CPA was prepared by grafting cationic polyacrylamide (CPA) synthesized from methacryloyloxy ethyltrimethyl ammonium chloride (DMC) and acrylamide (AM) onto sodium lignosulfonate (LS), and its roles and underlying mechanisms in sludge conditioning were investigated. The results showed that LS-g-CPA effectively improved the dewaterability of sludge, reducing the filtration resistance and filter cake moisture content of sludge from 0.61 ± 0.05 × 1012 m/kg to 0.14 ± 0.02 × 1012 m/kg and 85.64 ± 0.25 % to 76.84 ± 0.41 %, respectively. The dewatering performance of LS-g-CPA was positively correlated with the DMC/AM ratio. The quaternary ammonium groups brought by DMC disrupted the reticular structure of extracellular polymeric substances, exposing hydrophobic residues and releasing bound water. Nevertheless, the key to LS-g-CPA for improving sludge dewatering lies more in the amphoteric flocculant properties that enhance sludge flocculation and the octopus-type structure that provides good drainage channels. This study reveals that lignin-based flocculants are effective in improving the dewaterability of sludge, which provides direct evidence for their application in sludge dewatering.
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Affiliation(s)
- Shiqin Wang
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China
| | - Hongbo Chen
- College of Environment and Resources, Xiangtan University, Xiangtan 411105, China.
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An Q, Chen D, Tang Y, Hu Y, Feng Y, Qian K, Yin L. Adsorption of pyrolysis oil model compound (phenol) with plasma-modified hydro-chars and mechanism exploration. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:122611-122624. [PMID: 37971593 DOI: 10.1007/s11356-023-30904-y] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2023] [Accepted: 11/01/2023] [Indexed: 11/19/2023]
Abstract
Phenol is one of the important ingredients of pyrolysis oil, contributing to the high biotoxicity of pyrolysis oil. To promote the degradation and conversion of phenol during anaerobic digestion, cheap hydro-chars with high phenol adsorption capacity were produced. The phenol adsorption capabilities of the plain hydro-char, plasma modified hydro-char at 25 °C (HC-NH3-P-25) and 500 °C (HC-NH3-P-500) were evaluated, and their adsorption kinetics and thermodynamics were explored. Experimental results indicate that the phenol adsorption capability of HC-NH3-P-500 was the highest. The phenol adsorption kinetics of all samples followed the pseudo-second-order equation and interparticle diffusion model, indicating that the adsorption rate of phenol was controlled by interparticle diffusion and chemistry adsorption simultaneously. By DFT calculations, π-π stacking and hydrogen bond are the main interactions for phenol adsorption. It was observed that an enriched graphite N content decreased the average vertical distance between hydro-chars and phenol in π-π stacking complex, from 3.5120 to 3.4532 Å, causing an increase in the negative adsorption energy between phenol and hydro-char from 13.9330 to 23.4181 kJ/mol. For hydrogen bond complex, the average vertical distance decreased from 3.4885 to 3.3386 Å due to the increase in graphite N content; causing the corresponding negative adsorption energy increased from 19.0233 to 19.9517 kJ/mol. Additionally, the presence of graphite N in the hydro-char created a positive diffusion region and enhanced the electron density between hydro-char and phenol. Analyses suggest that enriched graphite N contributed to the adsorption complex stability, resulting in an improved phenol adsorption capacity.
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Affiliation(s)
- Qing An
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
| | - Dezhen Chen
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China.
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China.
| | - Yuzhen Tang
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
| | - Yuyan Hu
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
| | - Yuheng Feng
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
| | - Kezhen Qian
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
| | - Lijie Yin
- Thermal and Environmental Engineering Institute, Mechanical Engineering College, Tongji University, Shanghai, 201804, China
- Shanghai Engineering Research Center of Multi-Source Solid Wastes Co-Processing and Energy Utilization, Shanghai, 201804, China
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37
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Wang JY, Zhao B, An Q, Dan Q, Guo JS, Chen YP. The acceleration of aerobic sludge granulation by alternating organic loading rate: Performance and mechanism. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 347:119047. [PMID: 37778070 DOI: 10.1016/j.jenvman.2023.119047] [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: 07/17/2023] [Revised: 09/07/2023] [Accepted: 09/18/2023] [Indexed: 10/03/2023]
Abstract
As a highly promising treatment technology for wastewater, long start-up time is one of the bottlenecks hindering the widespread application of aerobic granular sludge (AGS). This study focused on exploring the possibility of alternating organic loading rate (OLR) in promoting AGS granulation. Under alternating OLR (3.6-14.4 kgCOD/m3·d), AGS granulation was significantly accelerated. The mean granule size under alternating load reached 234.6 μm at 17 d, while under constant OLR (7.2 kgCOD/m3·d), the mean granule size was only 179.2 μm. Moreover, the granule size maintained continuous growth even when the alternating OLR was changed to constant OLR. Alternating load significantly increased the content of extracellular polymeric substances (EPS), especially proteins (PN) in tightly bound EPS (TB-EPS), which was likely the main reason for accelerating AGS granulation. Moreover, alternating load reduced the hydrophilicity of EPS and promoted the content of proteins secondary structures that favored aggregation in TB-EPS, which were also beneficial for granulation. Microbial community results showed that alternating load might promote the enrichment of EPS producing bacteria, such as Thauera, Brevundimonas and Shinella. Meanwhile, the content of enzymes that regulated amino acids metabolism also increased under alternating load, which might be related to the increase of PN in EPS. These results further demonstrated that alternating load promoted granulation through EPS.
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Affiliation(s)
- Jin Yi Wang
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Bin Zhao
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China.
| | - Qiang An
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Qiao Dan
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Jin Song Guo
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - You Peng Chen
- Key Laboratory of the Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing, 400045, PR China; College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
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Jiang A, Pei W, Zhang R, Shah KJ, You Z. Toxic effects of aging mask microplastics on E. coli and dynamic changes in extracellular polymeric matter. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 899:165607. [PMID: 37474070 DOI: 10.1016/j.scitotenv.2023.165607] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/04/2023] [Revised: 07/15/2023] [Accepted: 07/15/2023] [Indexed: 07/22/2023]
Abstract
Contamination of disposable medical masks has become a growing problem globally in the wake of Covid-19 due to their widespread use and improper disposal. Three different mask layers, namely the outer layer, the meltblown (MB) filler layer and the inner layers release three different types of microplastics, whose physical and chemical properties change after prolonged environmental weathering. In this study, physical and chemical changes of mask microplastics before and after aging were characterized by different characterization techniques. The toxic effect and mechanism of aged mask microplastics on Escherichia coli (E. coli) were studied by measuring the growth inhibition of mask microplastics, the change in ATPase activity, the change in malondialdehyde content and reactive oxygen species production, and the release of the chemical composition of exopolymeric substances (EPS). The microplastics of the aged MB filter layer had the most significant inhibitory effect on E. coli growth, reaching 19.2 % after 36 h. Also, under the influence of mask microplastics, ATPase activity of E. coli was inhibited and a large amount of EPS was released. The chemical composition of EPS has also changed. This study proposed the possible toxicity mechanism of mask microplastics and the self-protection mechanism of E. coli, and provided a reference for future research on the toxic effects of mask microplastics on environmental organisms.
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Affiliation(s)
- Angrui Jiang
- College of Urban Construction, Nanjing Tech University, Nanjing, 211800, China; Yangtze River Innovation Center for Ecological Civilization, Nanjing, 211800, China.
| | - Wuxuan Pei
- College of Urban Construction, Nanjing Tech University, Nanjing, 211800, China; Yangtze River Innovation Center for Ecological Civilization, Nanjing, 211800, China.
| | - Rui Zhang
- College of Urban Construction, Nanjing Tech University, Nanjing, 211800, China; Yangtze River Innovation Center for Ecological Civilization, Nanjing, 211800, China.
| | - Kinjal J Shah
- College of Urban Construction, Nanjing Tech University, Nanjing, 211800, China.
| | - Zhaoyang You
- College of Urban Construction, Nanjing Tech University, Nanjing, 211800, China.
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Wang G, Huang X, Wang S, Yang F, Sun S, Yan P, Chen Y, Fang F, Guo J. Effect of food-to-microorganisms ratio on aerobic granular sludge settleability: Microbial community, potential roles and sequential responses of extracellular proteins and polysaccharides. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 345:118814. [PMID: 37591089 DOI: 10.1016/j.jenvman.2023.118814] [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: 06/05/2023] [Revised: 07/18/2023] [Accepted: 08/12/2023] [Indexed: 08/19/2023]
Abstract
The food-to-microorganism ratio (F/M) is an important parameter in wastewater biotreatment that significantly affects the granulation and settleability of aerobic granular sludge (AGS). Hence, understanding the long-term effects and internal mechanisms of F/M on AGS settling performance is essential. This study investigated the relationship between F/M and the sludge volume index (SVI) within a range of 0.23-2.50 kgCOD/(kgMLVSS·d). Thiothrix and Candidatus_Competibacter were identified as two dominant bacterial genera influencing AGS settling performance. With F/M increased from 0.27 kgCOD/(kgMLVSS·d) to 1.53 kgCOD/(kgMLVSS·d), the abundance of Thiothrix significantly increased from 0.20% to 27.02%, and the hydrophobicity of extracellular proteins (PN) decreased, which collectively reduced AGS settling performance. However, under high-F/M conditions, the gel-like polysaccharides (PS) effectively retained the granular biomass by binding to the highly abundant Thiothrix (53.65%). The progressive increment in biomass led to a concomitant reduction in F/M, resulting in the recovery of AGS settleability. In addition, two-dimensional correlation infrared spectroscopy analysis revealed the preferential responses of PN and PS to the increase and decrease of F/M, and the content and characteristics of PN and PS played important roles in granular settling. The study provides insight into the microbial composition and the potential role of extracellular polymer substances in the AGS sedimentation behavior, offering valuable theoretical support for stable AGS operation.
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Affiliation(s)
- Gonglei Wang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Xiaoxiao Huang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shuai Wang
- College of Environment Sciences and Engineering, Peking University, Beijing, 100871, China
| | - Fan Yang
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, China
| | - Shiting Sun
- 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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Jiang Y, Zhang X, Poh LS, Ng WJ. Effect of free nitrous acid on extracellular polymeric substances production and membrane fouling in a nitritation membrane bioreactor. CHEMOSPHERE 2023; 340:139913. [PMID: 37611766 DOI: 10.1016/j.chemosphere.2023.139913] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/01/2023] [Revised: 08/08/2023] [Accepted: 08/19/2023] [Indexed: 08/25/2023]
Abstract
The membrane bioreactor (MBR) with nitritation based nitrogen removal processes has attracted growing interest in recent years, although membrane fouling in the nitritation MBR is a challenging issue. In this study, the inhibitory effect of free nitrous acid (FNA) on microbial extracellular polymeric substances (EPS) production and membrane fouling in a nitritation MBR was investigated. Results showed that EPS played a critical role in the biofouling process, and EPS production was affected by FNA concentration. As FNA concentration increased from 5.10 × 10-3 mg N/L to 1.34 × 10-2 mg N/L, protein (PN) and polysaccharide (PS) contents increased from 8.20 to 60.28 mg/g VSS and 4.74-30.46 mg/g VSS, respectively. However, when FNA concentration was 1.48 × 10-2 mg N/L, PN and PS reduced by 20.0% and 10.9%, respectively, indicating that the higher FNA concentration could reduce EPS production. The EPS reduction could be attributed to reduction in the loosely bound (LB) and tightly bound (TB) EPS but not the soluble microbial products (SMP). It was further revealed that higher FNA concentrations up to 1.48 × 10-2 mg N/L consequently mitigate trans-membrane pressure (TMP) rate in terms of dTMP/dt by 25.5% in the nitritation MBR. High throughput sequencing analysis revealed that the increase in FNA led to enrichment of Nitrosomonas but reduction in heterotrophic bacteria. This study showed that the appropriate FNA concentration affected EPS production and hence membrane fouling, leading to the possibility of membrane fouling mitigation by in-situ generated FNA in the nitritation MBR.
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Affiliation(s)
- Yishuai Jiang
- Advanced Environmental Biotechnology Centre, Nanyang Environment and Water Research Institute, Nanyang Technological University, 1 Cleantech Loop, Clean Tech One, 637141, Singapore; Environmental Sustainability Team, Kajima Technical Research Institute Singapore, 19 Changi Business Park Crescent, #05-15 The GEAR, 489690, Singapore.
| | - Xiaoyuan Zhang
- Engineering Laboratory of Low-Carbon Unconventional Water Resources Utilization and Water Quality Assurance, College of Environmental Science and Engineering, Nankai University, Tianjin, 300350, China
| | - Leong Soon Poh
- NSL OilChem Waste Management PTE. LTD., 7 Tuas Avenue 10, 639131, Singapore
| | - Wun Jern Ng
- School of Civil and Environmental Engineering, Nanyang Technological University, 50 Nanyang Avenue, 639798, Singapore
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Zhi M, Zhao Y, Zeng X, Maddela NR, Xiao Y, Chen Y, Prasad R, Zhou Z. Filamentous cyanobacteria and hydrophobic protein in extracellular polymeric substances facilitate algae-bacteria aggregation during partial nitrification. Int J Biol Macromol 2023; 251:126379. [PMID: 37595699 DOI: 10.1016/j.ijbiomac.2023.126379] [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: 02/27/2023] [Revised: 07/08/2023] [Accepted: 08/15/2023] [Indexed: 08/20/2023]
Abstract
In algae-bacteria symbiotic wastewater treatment, the excellent settling performance of algae-bacteria aggregates is critical for biomass separation and recovery. Here, the composition of extracellular polymeric substances (EPS), microbial profiles, and functional genes of algae-bacteria aggregates were investigated at different solid retention times (SRTs) (10, 20, and 40 d) during partial nitrification in photo sequencing bioreactors (PSBRs). Results showed that SRTs greatly influenced the nitrogen transformation and the formation and morphological structure of algae-bacteria aggregates. The highest nitrite accumulation, the largest particle size (~1.54 mm) and the best settling performance were observed for the algae-bacteria aggregates in the PSBR with an SRT of 10 d, where the abundant occurrence of filamentous cyanobacteria with the highest ratio of chlorophyll a/b and the lowest EPS amount with the highest protein-to-polysaccharide ratio were observed. In particular, the EPS at 10 d of SRT contained a higher amount of protein-related hydrophobic groups and a lower ratio of α-helix/(β-sheet + random coil), indicating a looser protein structure, which might facilitate the formation and stabilization of algae-bacteria aggregates. Moreover, algal-bacterial aggregation greatly depended on the composition and evolution of filamentous cyanobacteria (unclassified _o__Oscillatoriales and Phormidium accounted for 56.29 % of the identified algae at SRT 10 d). The metagenomic analysis further revealed that functional genes related to amino acid metabolism (e.g., genes of phenylalanine, tyrosine, and tryptophan biosynthesis) were expressed at high levels within 10 d of SRT. Overall, this study demonstrates the influence of EPS structures and filamentous cyanobacteria on algae-bacteria aggregation and reveals the biological mechanisms driving photogranule structure and function.
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Affiliation(s)
- Mei Zhi
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China
| | - Yiying Zhao
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Xinyu Zeng
- College of Resources and Environment, Southwest University, Chongqing 400715, China
| | - Naga Raju Maddela
- Departamento de Ciencias Biológicas, Facultad de Ciencias de la Salud, Universidad Técnica de Manabí, Portoviejo 130105, Ecuador
| | - Yeyuan Xiao
- Department of Civil and Environmental Engineering, Shantou University, Shantou 515063, China
| | - Yucheng Chen
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China
| | - Ram Prasad
- Department of Botany, Mahatma Gandhi Central University, Motihari, Bihar 845401, India.
| | - Zhongbo Zhou
- College of Resources and Environment, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center of Rural Cleaner Production, Chongqing 400715, China.
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Cai W, Zhang P, Xing X, Lyu L, Zhang H, Hu C. Synergetic effects of catalyst-surface dual-electric centers and microbes for efficient removal of ciprofloxacin in water. WATER RESEARCH 2023; 245:120541. [PMID: 37690413 DOI: 10.1016/j.watres.2023.120541] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Revised: 08/25/2023] [Accepted: 08/27/2023] [Indexed: 09/12/2023]
Abstract
Antibiotics and antibiotic resistance genes (ARGs) are still a problem in biological treatment. Herein, we propose a synergetic strategy between microbes and dual-electric centers catalysts (CCN/Cu-Al2O3/ceramsite) for Ciprofloxacin (CIP)-contained (5 mg/L) water treatment in an up-flow biological filter. CIP was cleaved into small molecules by the catalyst, bringing a 57.6% removal and reducing 10.5% ARG. The characterization results verified that a Cu-π electrostatic force occurs on the catalyst surface, forming electron-rich areas around Cu and electron-poor areas at the carbon-doped g-C3N4 (CCN) aromatic ring. Thus, the electrons of adsorbed CIP were delocalized and then captured by the adsorbed extracellular polymeric substance at the electron-rich areas. Therefore, the synergetic process weakened the stress of CIP on bacteria and reduced ARG accumulation. It also enriched more electro-active bacteria on the surface of CCN/Cu-Al2O3/ceramsite, promoting the expression of extracellular electron transfer-related genes and reconstructing the energy metabolism mode. This result provides an opportunity for refractory antibiotic treatment in the biological process.
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Affiliation(s)
- Wu Cai
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Peng Zhang
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Xueci Xing
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Lai Lyu
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China
| | - Han Zhang
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
| | - Chun Hu
- Institute of Environmental Research at Greater Bay, Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, China.
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Yao Y, Wei Y, Li J, Han R, Jing C, Liu R, Niu Q. Microbial electron flow promotes naphthalene degradation in anaerobic digestion in the presence of nitrate electron acceptor: Focus on electron flow regulation and microbial interaction succession. JOURNAL OF HAZARDOUS MATERIALS 2023; 459:132293. [PMID: 37597391 DOI: 10.1016/j.jhazmat.2023.132293] [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: 06/05/2023] [Revised: 08/11/2023] [Accepted: 08/12/2023] [Indexed: 08/21/2023]
Abstract
Microbial electron flow (MEF) is produced from microbial degradation of organic compounds. Regulating MEF to promote organic pollutants biodegradation such as naphthalene (Nap) is a potential way but remains a lack of theoretical basis. Here, we regulated MEF by adding electron acceptor NO3- to achieve 2.6 times increase of Nap biodegradation with cyclodextrin as co-metabolism carbon source. With the NO3- addition, the genes inhibited by Nap of electron generation significantly up-regulated. Especially, key genes ubiD and nahD for anaerobic Nap degradation significantly up-regulated respectively 3.7 times and 6.7 times. Moreover, the ability of electron transfer in MEF was also improved consistent with 7.2 times increase of electron transfer system (ETS) activity. Furthermore, total 60 metagenome-assembled genomes (MAGs) were reconstructed through the metagenomic sequencing data with assembly and binning strategies. Interestingly, it was also first found that the Klebsiella MAG. SDU (Shandong University) 14 had the ability of simultaneous Nap biodegradation and denitrification. Our results firstly offered an effective method of regulating MEF to promote polycyclic aromatic hydrocarbons (PAHs) degradation and simultaneous methanogenesis.
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Affiliation(s)
- Yilin Yao
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Yanhao Wei
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Jingyi Li
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Ruotong Han
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China
| | - Chuanyong Jing
- Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, Shandong University, Qingdao, Shandong 266237, China
| | - Rutao Liu
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China; Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, Shandong University, Qingdao, Shandong 266237, China; Qingdao Key Laboratory of Marine Pollutant Prevention, Shandong University, Qingdao, Shandong 266237, China.
| | - Qigui Niu
- China-America CRC for Environment & Health, School of Environmental Science and Engineering, Shandong University, Qingdao, Shandong 266237, China; Shandong Provincial Key Laboratory of Water Pollution Control and Resource Reuse, Shandong University, Qingdao, Shandong 266237, China; Qingdao Key Laboratory of Marine Pollutant Prevention, Shandong University, Qingdao, Shandong 266237, China.
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Zeng Y, Wang Z, Pan Z, Shen L, Teng J, Lin H, Zhang J. Novel thermodynamic mechanisms of co-conditioning with polymeric aluminum chloride and polyacrylamide for improved sludge dewatering: A paradigm shift in the field. ENVIRONMENTAL RESEARCH 2023; 234:116420. [PMID: 37327838 DOI: 10.1016/j.envres.2023.116420] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2023] [Revised: 05/25/2023] [Accepted: 06/13/2023] [Indexed: 06/18/2023]
Abstract
This study investigated the combined effects of polymeric aluminum chloride (PAC) and polyacrylamide (PAM) on sludge dewatering, aiming to unveil underlying mechanisms. Co-conditioning with 15 mg g-1 PAC and 1 mg g-1 PAM achieved optimal dewatering, reducing specific filtration resistance (SFR) of co-conditioned sludge to 4.38 × 1012 m-1kg-1, a mere 48.1% of raw sludge's SFR. Compared with the CST of raw sludge (36.45 s), sludge sample can be significantly reduced to 17.7 s. Characterization tests showed enhanced neutralization and agglomeration in co-conditioned sludge. Theoretical calculations revealed elimination of interaction energy barriers between sludge particles post co-conditioning, converting sludge surface from hydrophilic (3.03 mJ m-2) to hydrophobic (-46.20 mJ m-2), facilitating spontaneous agglomeration. Findings explain improved dewatering performance. Based on Flory-Huggins lattice theory, connection between polymer structure and SFR was established. Raw sludge formation triggered significant change in chemical potential, increasing bound water retention capacity and SFR. In contrast, co-conditioned sludge exhibited thinnest gel layer, reducing SFR and significantly improving dewatering. These findings represent a paradigm shift, shedding new light on fundamental thermodynamic mechanisms of sludge dewatering with different chemical conditioning.
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Affiliation(s)
- Yansha Zeng
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Zhe Wang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Zhenxiang Pan
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Liguo Shen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Jiaheng Teng
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
| | - Jianzhen Zhang
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua, 321004, China; Key Laboratory of Watershed Earth Surface Processes and Ecological Security, Zhejiang Normal University, Jinhua, 321004, China.
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Cao M, Yang D, Wang F, Zhou B, Chen H, Yuan R, Sun K. Extracellular polymeric substances altered the physicochemical properties of molybdenum disulfide nanomaterials to mitigate its toxicity to Chlorella vulgaris. NANOIMPACT 2023; 32:100485. [PMID: 37778438 DOI: 10.1016/j.impact.2023.100485] [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: 08/07/2023] [Revised: 09/23/2023] [Accepted: 09/26/2023] [Indexed: 10/03/2023]
Abstract
Although the toxic effects of two-dimensional nanomaterials (2D-NMs) have been widely reported, the influence of extracellular polymeric substances (EPS) on the environmental fate and risk of 2D-NMs in aquatic environments is largely unknown, and the processes and mechanisms involved remain to be revealed. Herein, we investigated the impact of EPS secreted by microalgae (Chlorella vulgaris (C. vulgaris)) on the environmental transformation and risk of molybdenum disulfide (MoS2). We found that the attachment of EPS increased the thickness of MoS2 (from 2 nm to 5 nm), changed it from a monolayer sheet to a fuzzy multilayer structure, and promoted the formation of defects on MoS2. The blue-shift of the peak associated with the plasmon resonances in the 1 T phase and the generation of electron-hole pairs suggested that EPS altered the surface electronic structure of MoS2. EPS interacted mainly with the S atoms on the 1 T phase, and the attachment of EPS promoted the oxidation of MoS2. The reduction in hydrodynamic diameter (Dh) and the decrease in zeta potential indicated that EPS inhibited the agglomeration behavior of MoS2 and enhanced its dispersion and stability in aqueous media. Notably, EPS reduced the generation of free radicals (superoxide anion (•O2-), singlet oxygen (1O2), and hydroxyl radicals (•OH-)). Furthermore, EPS mitigated the toxicity of MoS2 to C. vulgaris, such as attenuated reduction in biomass and chlorophyll content. Compared to pristine MoS2, MoS2 + BG11 + EPS exhibited weaker oxidative stress, membrane damage and lipid peroxidation. The adsorption of EPS on MoS2 surface reduced the attachment sites of MoS2, making MoS2 less likely to be enriched on the cell surface. The findings have significant contribution for understanding the interactions between EPS and MoS2 in aquatic ecosystems, providing scientific guidance for risk assessment of 2D-NMs.
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Affiliation(s)
- Manman Cao
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China
| | - Donghong Yang
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Fei Wang
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China.
| | - Beihai Zhou
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Huilun Chen
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Rongfang Yuan
- School of Energy & Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, University of Science and Technology Beijing, 30 Xueyuan Road, 100083 Beijing, China
| | - Ke Sun
- School of Environment, Beijing Normal University, 19 Xinjiekouwai Street, 100875 Beijing, China
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Fan X, Wang Y, Zhang D, Zhang S, Liu C, Liu M. A comprehensive assessment on sludge conditioning by pyrite acid eluent-activated peroxymonosulfate based on dewaterability, heavy metals risk and ore recovery. WASTE MANAGEMENT (NEW YORK, N.Y.) 2023; 170:82-92. [PMID: 37556939 DOI: 10.1016/j.wasman.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/17/2023] [Revised: 06/30/2023] [Accepted: 08/01/2023] [Indexed: 08/11/2023]
Abstract
Wastewater activated sludge (WAS) has poor dewaterability and contains heavy metals (HMs), limiting its land application. Therefore, in this study, a novel pyrite acid eluent-activated peroxymonosulfate (Fe2+pyrite/PMS) conditioning approach that can completely recover the residual pyrite and greatly reduce acid use was developed to improve WAS dewaterability, and the HMs chemical speciation and risks of conditioned WAS were assessed. Our results showed that under the optimized operational parameters, the capillary suction time (CST) and water content (Wc) of WAS decreased by 46.03% and 7.75%, respectively. Furthermore, during Fe2+pyrite/PMS conditioning processing, sulfate radical (SO4-) destroyed the extracellular polymeric substances (EPS) matrix, causing bound water release and the decrease of proteins/polysaccharides in outer layered EPS, even the decomposition of some protein-N in tightly bound EPS (TB-EPS) into inorganic-N. In addition, although the total concentration of HMs in the conditioned WAS matrix increased, the Ni concentration decreased in the solid fraction. Further, the risk assessment code (RAC) levels did not increase, and the eco-toxicity of Cr became weakened after Fe2+pyrite/PMS conditioning. However, after acid extraction, the pyrite residue had worsened recycle performance because the passivation layer contained S0/Sn2- on its surface, and no additional elements were detected in the pyrite residue, which had almost no effect on its further usage.
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Affiliation(s)
- Xiaoyang Fan
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Yili Wang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Daxin Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Shuting Zhang
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Chenyang Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
| | - Meilin Liu
- Beijing Key Lab for Source Control Technology of Water Pollution, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China; Engineering Research Center for Water Pollution Source Control & Eco-remediation, College of Environmental Science and Engineering, Beijing Forestry University, Beijing 100083, China.
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Ou Z, Chen X, Wu X, Zhou C, Zhang K, Luo J, Fang F, Sun Y, Li M, Feng Q. N-acyl homoserine lactone mediating initial adhesion of microalgal biofilm formation. ENVIRONMENTAL RESEARCH 2023; 233:116446. [PMID: 37331555 DOI: 10.1016/j.envres.2023.116446] [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: 03/30/2023] [Revised: 06/07/2023] [Accepted: 06/16/2023] [Indexed: 06/20/2023]
Abstract
While pioneering methods have demonstrated that bacterial N-acyl homoserine lactone (AHL) signaling molecules can influence the growth and self-aggregation of suspended microalgae, whether AHLs can affect the initial adhesion to a carrier has remained an open question. Here we revealed that the microalgae exhibited different adhesion potential under AHL mediation, where the performance was affiliated to both AHL types and concentrations. The result can be well explained by the interaction energy theory, where the energy barrier between the carriers and the cells varied due to AHL mediation. Depth analyses revealed that AHL acted through modifying the properties of the surface electron donor of the cells, which were dependent upon three major components, i.e., extracellular protein (PN) secretion, the PN secondary structure, and the PN amino acid composition. These findings expand the known diversity of AHLs mediation on microalgal initial adhesion and metabolisms, which may interface with other major cycles and become helpful to theoretically guide the application of AHLs in microalgal culture and harvesting.
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Affiliation(s)
- Zixuan Ou
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Xindi Chen
- State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering, College of Harbor, Coastal and Offshore Engineering, Hohai University, Nanjing, PR China
| | - Xinming Wu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Changren Zhou
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Kaijie Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Jingyang Luo
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Fang Fang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China
| | - Yinqiang Sun
- School of Chemistry & Chemical Engineering, Anhui University, Anhui, 230039, PR China
| | - Ming Li
- College of Resources and Environment, Northwest A&F University, Yangling, Shanxi, 712100, PR China
| | - Qian Feng
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Ministry of Education, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China; College of Environment, Hohai University, 1 Xikang Road, Nanjing, 210098, PR China.
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48
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Yang B, Liang W, Bin L, Chen W, Chen X, Li P, Wen S, Huang S, Tang B. Insights into the life-cycle of aerobic granular sludge in a continuous flow membrane bioreactor by tracing its heterogeneous properties at different stages. WATER RESEARCH 2023; 243:120419. [PMID: 37536250 DOI: 10.1016/j.watres.2023.120419] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2023] [Revised: 07/24/2023] [Accepted: 07/25/2023] [Indexed: 08/05/2023]
Abstract
This work gave insights into the life-cycle of aerobic granular sludge (AGS) by tracing its heterogeneity in the basic properties at different stages in a closed system (a continuous flow membrane bioreactor, MBR), including physical and chemical characteristics and microbial communities. The results indicate that the entire life-cycle consists of the following four stages, namely, the initial, growing, mature and cleaved stages, where multiple AGS properties synergistically affect the rheological properties of the AGS over its life-cycle. The storage modulus (G') of AGS reached its maximum value at the mature stage, whose value was significantly and positively correlated with the protein (PN) in extracellular polymeric substances (EPS) and granule size, specifically the peak area of granule size distribution, but this value was strongly and negatively correlated with the roughness. The AGS at the mature stage would be more vulnerable to be destroyed than that at other stages under the condition of higher shear strain, such as γ = 50%, which was associated with larger granule size and fewer polysaccharide (PS)-related functional groups (especially in the soluble microbial products (SMPs) in the outermost layer of AGS), and the decrease in PS was correlated with a higher relative abundance of Chloroflexi. Additionally, the value of shear strain that AGS was subjected to had a good linear correlation (R2=0.993) with the Young's modulus, which indicated the ability of AGS to resist deformation improved with increasing values of shear strain.
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Affiliation(s)
- Biao Yang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Weifeng Liang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Liying Bin
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Weirui Chen
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Xinyi Chen
- Guangdong Guangshen Environmental Protection Technology Co., Ltd., Guangzhou, 510006, PR China
| | - Ping Li
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Shanglong Wen
- Guangdong Guangshen Environmental Protection Technology Co., Ltd., Guangzhou, 510006, PR China
| | - Shaosong Huang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China
| | - Bing Tang
- School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou, 510006, PR China.
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Wu S, Huo H, Shi Y, Zhang F, Gu T, Li Z. Extraction and application of extracellular polymeric substances from fungi. ADVANCES IN APPLIED MICROBIOLOGY 2023; 125:79-106. [PMID: 38783725 DOI: 10.1016/bs.aambs.2023.08.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Extracellular polymeric substances (EPS) are extracellular metabolites of microorganisms, highly associated with microbial function, adaptation, and growth. The main compounds in EPS have been revealed to be proteins, polysaccharides, nucleic acids, humic substances, lipids, etc. EPS are not only biomass, but also a biogenic material. EPS have high specific surface, abundant functional groups, and excellent degradability. In addition, they are more extensible to the environment than the microbial cells themselves, which exhibits their huge advantages. Therefore, they have been applied in many fields, such as the environment, ecosystem, basic commodities, and medicine. However, the functions of EPS highly depend on the suitable extraction process, as different extraction methods have different effects on their composition, structure, and function. There are many types of EPS extraction methods, in which physical and chemical methods have been widely utilized. This review summarizes the extraction methods and applications of EPS. In addition, it considers some important gaps in current knowledge, and indicates perspectives of EPS for their future study.
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Affiliation(s)
- Sijia Wu
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China
| | - Hongxun Huo
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China
| | - Yixiao Shi
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China
| | - Feiran Zhang
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China
| | - Tingting Gu
- State Key Laboratory of Crop Genetics and Germplasm Enhancement, College of Horticulture, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China
| | - Zhen Li
- College of Resources and Environmental Sciences, Nanjing Agricultural University, Nanjing, Jiangsu, P.R. China; Ministry of Natural Resources National Research Center for Geoanalysis, Key Laboratory of Eco-geochemistry, Beijing, P.R. China; Jiangsu Provincial Key Lab of Organic Solid Waste Utilization, Nanjing Agricultural University, Nanjing, P.R. China.
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50
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White C, Antell E, Schwartz SL, Lawrence JE, Keren R, Zhou L, Yu K, Zhuang W, Alvarez-Cohen L. Synergistic interactions between anammox and dissimilatory nitrate reducing bacteria sustains reactor performance across variable nitrogen loading ratios. Front Microbiol 2023; 14:1243410. [PMID: 37637134 PMCID: PMC10450351 DOI: 10.3389/fmicb.2023.1243410] [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: 06/20/2023] [Accepted: 07/13/2023] [Indexed: 08/29/2023] Open
Abstract
Anaerobic ammonium oxidizing (anammox) bacteria are utilized for high efficiency nitrogen removal from nitrogen-laden sidestreams in wastewater treatment plants. The anammox bacteria form a variety of competitive and mutualistic interactions with heterotrophic bacteria that often employ denitrification or dissimilatory nitrate reduction to ammonium (DNRA) for energy generation. These interactions can be heavily influenced by the influent ratio of ammonium to nitrite, NH4+:NO2-, where deviations from the widely acknowledged stoichiometric ratio (1:1.32) have been demonstrated to have deleterious effects on anammox efficiency. Thus, it is important to understand how variable NH4+:NO2- ratios impact the microbial ecology of anammox reactors. We observed the response of the microbial community in a lab scale anammox membrane bioreactor (MBR) to changes in the influent NH4+:NO2- ratio using both 16S rRNA gene and shotgun metagenomic sequencing. Ammonium removal efficiency decreased from 99.77 ± 0.04% when the ratio was 1:1.32 (prior to day 89) to 90.85 ± 0.29% when the ratio was decreased to 1:1.1 (day 89-202) and 90.14 ± 0.09% when the ratio was changed to 1:1.13 (day 169-200). Over this same timespan, the overall nitrogen removal efficiency (NRE) remained relatively unchanged (85.26 ± 0.01% from day 0-89, compared to 85.49 ± 0.01% from day 89-169, and 83.04 ± 0.01% from day 169-200). When the ratio was slightly increased to 1:1.17-1:1.2 (day 202-253), the ammonium removal efficiency increased to 97.28 ± 0.45% and the NRE increased to 88.21 ± 0.01%. Analysis of 16 S rRNA gene sequences demonstrated increased relative abundance of taxa belonging to Bacteroidetes, Chloroflexi, and Ignavibacteriae over the course of the experiment. The relative abundance of Planctomycetes, the phylum to which anammox bacteria belong, decreased from 77.19% at the beginning of the experiment to 12.24% by the end of the experiment. Analysis of metagenome assembled genomes (MAGs) indicated increased abundance of bacteria with nrfAH genes used for DNRA after the introduction of lower influent NH4+:NO2- ratios. The high relative abundance of DNRA bacteria coinciding with sustained bioreactor performance indicates a mutualistic relationship between the anammox and DNRA bacteria. Understanding these interactions could support more robust bioreactor operation at variable nitrogen loading ratios.
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Affiliation(s)
- Christian White
- Department of Civil & Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
| | - Edmund Antell
- Department of Civil & Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
| | - Sarah L. Schwartz
- Department of Civil & Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
| | | | - Ray Keren
- Department of Civil & Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
| | - Lijie Zhou
- College of Chemistry and Environmental Engineering, Shenzhen University, Shenzhen, China
| | - Ke Yu
- School of Environment and Energy, Shenzhen Graduate School, Peking University, Shenzhen, China
| | - Weiqin Zhuang
- Department of Civil & Environmental Engineering, University of Auckland, Auckland, New Zealand
| | - Lisa Alvarez-Cohen
- Department of Civil & Environmental Engineering, University of California, Berkeley, Berkeley, CA, United States
- Earth and Environmental Sciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, United States
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