1
|
Zhang X, Zhao Y, Wang Y, Qian H, Xing J, Joseph A, Rene ER, Li J, Zhu N. The interplay of hematite and photic biofilm triggers the acceleration of biotic nitrate removal. CHEMOSPHERE 2024; 358:142136. [PMID: 38692363 DOI: 10.1016/j.chemosphere.2024.142136] [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: 02/05/2024] [Revised: 04/22/2024] [Accepted: 04/23/2024] [Indexed: 05/03/2024]
Abstract
The soil-water interface is replete with photic biofilm and iron minerals; however, the potential of how iron minerals promote biotic nitrate removal is still unknown. This study investigates the physiological and ecological responses of photic biofilm to hematite (Fe2O3), in order to explore a practically feasible approach for in-situ nitrate removal. The nitrate removal by photic biofilm was significantly higher in the presence of Fe2O3 (92.5%) compared to the control (82.8%). Results show that the presence of Fe2O3 changed the microbial community composition of the photic biofilm, facilitates the thriving of Magnetospirillum and Pseudomonas, and promotes the growth of photic biofilm represented by the extracellular polymeric substance (EPS) and the content of chlorophyll. The presence of Fe2O3 also induces oxidative stress (•O2-) in the photic biofilm, which was demonstrated by electron spin resonance spectrometry. However, the photic biofilm could improve the EPS productivity to prevent the entrance of Fe2O3 to cells in the biofilm matrix and mitigate oxidative stress. The Fe2O3 then promoted the relative abundance of Magnetospirillum and Pseudomonas and the activity of nitrate reductase, which accelerates nitrate reduction by the photic biofilm. This study provides an insight into the interaction between iron minerals and photic biofilm and demonstrates the possibility of combining biotic and abiotic methods to improve the in-situ nitrate removal rate.
Collapse
Affiliation(s)
- Xiguo Zhang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Yanhui Zhao
- Changjiang Basin Ecology and Environment Monitoring and Scientific Research Center, Changjiang Basin Ecology and Environment Administration, Ministry of Ecology and Environment, Wuhan, 430010, China
| | - Yimin Wang
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Haoliang Qian
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Jun Xing
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Akaninyene Joseph
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Eldon R Rene
- Department of Water Supply, Sanitation and Environmental Engineering, IHE Delft Institute for Water Education, Westvest 7, 2611AX, Delft, the Netherlands
| | - Jizhou Li
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China
| | - Ningyuan Zhu
- Key Laboratory of Integrated Regulation and Resource Development on Shallow Lake of Ministry of Education, College of Environment, Hohai University, Nanjing, 210098, China; Institute of Soil Sciences, Chinese Academy of Sciences, 71 East Beijing Road, 210008, China.
| |
Collapse
|
2
|
Yao J, Qi J, Sun J, Qian X, Chen J. Enhancement of nitrate reduction in microbial fuel cells by acclimating biocathode potential: Performance, microbial community, and mechanism. BIORESOURCE TECHNOLOGY 2024; 398:130522. [PMID: 38437965 DOI: 10.1016/j.biortech.2024.130522] [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: 01/01/2024] [Revised: 03/01/2024] [Accepted: 03/01/2024] [Indexed: 03/06/2024]
Abstract
The enhancement of nitrate reduction in microbial fuel cells (MFCs) by acclimating biocathode potential was studied. An MFC system was started up, and measured by cyclic voltammetry to determine a suitable potential region for acclimating biocathode. The experimental results revealed that potential acclimation could efficiently improve denitrification performance by relieving the phenomenon of nitrite accumulation, and optimum performance was obtained at -0.4 V with a total nitrogen removal efficiency of 87.4 %. Subsequently, the characteristics of electron transfer behaviors were measured, suggesting that a positive correlation between nitrate reduction and the contribution of direct electron transfer emerged. Furthermore, a denitrification mechanism was proposed. The results indicated that potential acclimation was conducive to enhancing denitrifying enzyme activity and that the electron transport system activity could be increased by 5.8 times. This study provides insight into the electron transfer characteristics and denitrification mechanisms in MFCs for nitrate reduction at specific acclimatization potentials.
Collapse
Affiliation(s)
- Jiachao Yao
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China; Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, Zhejiang Shuren University, Hangzhou 310015, China
| | - Jiayi Qi
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China
| | - Jiamo Sun
- College of Biological and Environmental Engineering, Zhejiang Shuren University, Hangzhou 310015, China
| | - Xiaofei Qian
- Interdisciplinary Research Academy, Zhejiang Shuren University, Hangzhou 310015, China
| | - Jun Chen
- Key Laboratory of Pollution Exposure and Health Intervention of Zhejiang Province, Zhejiang Shuren University, Hangzhou 310015, China; Interdisciplinary Research Academy, Zhejiang Shuren University, Hangzhou 310015, China.
| |
Collapse
|
3
|
Tian G, Kong Z, Zhang Y, Qiu L, Wang H, Yan Q. Simultaneous ammonia and nitrate removal by novel integrated partial denitrification-anaerobic ammonium oxidation-bioelectrochemical system. BIORESOURCE TECHNOLOGY 2024; 396:130428. [PMID: 38341044 DOI: 10.1016/j.biortech.2024.130428] [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: 12/13/2023] [Revised: 02/03/2024] [Accepted: 02/05/2024] [Indexed: 02/12/2024]
Abstract
The current study explored the performance of an integrated partial denitrification-anaerobic ammonium oxidation (anammox)-bioelectrochemical system on simultaneous removal of ammonia nitrogen and nitrate nitrogen. Different operational conditions were selected to optimize critical parameters of the process for improving nitrogen removal. The results indicated that more than 90 % of total inorganic nitrogen removal efficiency was achieved under the optimal conditions: ammonia nitrogen/nitrate nitrogen ratio of 1:2, external resistance of 200 Ω and inoculation volume ratio of anammox bacteria/denitrifying at 2:1. Improved nitrogen removal under the optimal conditions were confirmed by microbial community changes (Candidatus Brocadia and Thiobacillus) and enhanced of nitrogen metabolism-related genes (hao, hzsA/C and hdh). Increases of Limnobacter indicated an enhanced electron transfer efficiency. Overall, high-efficiency and stable nitrogen removal efficiency without nitrite nitrogen accumulation could be achieved by the integrated system under the optimal conditions, providing novel insights for simultaneous treatment of domestic wastewater and groundwater.
Collapse
Affiliation(s)
- Gengxu Tian
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Ziang Kong
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China
| | - Yifeng Zhang
- Department of Environmental Engineering, Technical University of Denmark, DK-2800 Kgs. Lyngby, Denmark
| | - Liwei Qiu
- Changzhou Cheff Environmental Protection Technology Co., Ltd, Changzhou 213164, China
| | - Han Wang
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China.
| | - Qun Yan
- School of Environmental and Civil Engineering, Jiangnan University, Wuxi 214122, China; Jiangsu Key Laboratory of Anaerobic Biotechnology, Wuxi 214122, China; Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, Suzhou 215011, China
| |
Collapse
|
4
|
Xia Z, Ng HY, Xu D, Bae S. Lumen air pressure regulated multifunctional microbiotas in membrane-aerated biofilm reactors for simultaneous nitrogen removal and antibiotic elimination from aquaculture wastewater. WATER RESEARCH 2024; 251:121102. [PMID: 38198973 DOI: 10.1016/j.watres.2024.121102] [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: 09/27/2023] [Revised: 12/19/2023] [Accepted: 01/02/2024] [Indexed: 01/12/2024]
Abstract
In this study, two membrane-aerated biofilm reactors (MABRs) were constructed: one solely utilizing biofilm and another hybrid MABR (HMABR) incorporating both suspended-sludge and biofilm to treat low C/N aquaculture wastewater under varying lumen air pressure (LAP). Both HMABR and MABR demonstrated superior nitrogen removal than conventional aeration reactors. Reducing LAP from 10 kPa to 2 kPa could enhance denitrification processes without severely compromising nitrification, resulting in an increase in total inorganic nitrogen (TIN) removal from 50.2±3.1 % to 71.6±1.0 %. The HMABR exhibited better denitrification efficacy than MABR, underscoring its potential for advanced nitrogen removal applications. A decline in LAP led to decreased extracellular polymeric substance (EPS) production, which could potentially augment reactor performance by minimizing mass transfer resistance while maintaining microbial matrix stability and function. Gene-centric metagenomics analysis revealed decreasing LAP impacted nitrogen metabolic potentials and electron flow pathways. The enrichment of napAB at higher LAP and the presence of complete ammonia oxidation (Comammox) Nitrospira at lower LAP indicated aerobic denitrification and Comammox processes in nitrogen removal. Multifunctional microbial communities developed under LAP regulation, diversifying the mechanisms for simultaneous nitrification-denitrification. Increased denitrifying gene pool (narGHI, nirK, norB) and enzymatic activity at a low LAP can amplify denitrification by promoting denitrifying genes and electron flow towards denitrifying enzymes. Sulfamethoxazole (SMX) was simultaneously removed with efficiency up to 80.2 ± 3.7 %, mainly via biodegradation, while antibiotic resistome and mobilome were propagated. Collectively, these findings could improve our understanding of nitrogen and antibiotic removal mechanisms under LAP regulation, offering valuable insights for the effective design and operation of MABR systems in aquaculture wastewater treatment.
Collapse
Affiliation(s)
- Zhengang Xia
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore; National University of Singapore (Suzhou) Research Institute, Suzhou 215123, China
| | - How Yong Ng
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore; Center for Water Research, Advanced Institute of Natural Sciences, Beijing Normal University at Zhuhai, Zhuhai 519087, China.
| | - Dong Xu
- National University of Singapore (Suzhou) Research Institute, Suzhou 215123, China
| | - Sungwoo Bae
- Department of Civil and Environmental Engineering, National University of Singapore, 1 Engineering Drive 2, 117576, Singapore.
| |
Collapse
|