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Zhang L, Li W, Li J, Wang Y, Xie H, Zhao W. A novel iron-mediated nitrogen removal technology of ammonium oxidation coupled to nitrate/nitrite reduction: Recent advances. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2022; 319:115779. [PMID: 35982573 DOI: 10.1016/j.jenvman.2022.115779] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2022] [Revised: 07/15/2022] [Accepted: 07/15/2022] [Indexed: 06/15/2023]
Affiliation(s)
- Lihong Zhang
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China; Gansu Membrane Science and Technology Research Institute Co.,Ltd., Lanzhou, 730020, People's Republic of China; Key Laboratory for Resources Utilization Technology of Unconventional Water of Gansu Province, Lanzhou, 730020, People's Republic of China
| | - Wenxuan Li
- NUS Environmental Research Institute, National University of Singapore, 5A Engineering Drive 1, #02-01 T-Lab Building, Singapore, 117411, Singapore
| | - Jie Li
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China.
| | - Ya'e Wang
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
| | - Huina Xie
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
| | - Wei Zhao
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
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Pang S, Li N, Luo H, Luo X, Shen T, Yang Y, Jiang J. Autotrophic Fe-Driven Biological Nitrogen Removal Technologies for Sustainable Wastewater Treatment. Front Microbiol 2022; 13:895409. [PMID: 35572701 PMCID: PMC9100419 DOI: 10.3389/fmicb.2022.895409] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/13/2022] [Accepted: 04/08/2022] [Indexed: 11/13/2022] Open
Abstract
Fe-driven biological nitrogen removal (FeBNR) has become one of the main technologies in water pollution remediation due to its economy, safety and mild reaction conditions. This paper systematically summarizes abiotic and biotic reactions in the Fe and N cycles, including nitrate/nitrite-dependent anaerobic Fe(II) oxidation (NDAFO) and anaerobic ammonium oxidation coupled with Fe(III) reduction (Feammox). The biodiversity of iron-oxidizing microorganisms for nitrate/nitrite reduction and iron-reducing microorganisms for ammonium oxidation are reviewed. The effects of environmental factors, e.g., pH, redox potential, Fe species, extracellular electron shuttles and natural organic matter, on the FeBNR reaction rate are analyzed. Current application advances in natural and artificial wastewater treatment are introduced with some typical experimental and application cases. Autotrophic FeBNR can treat low-C/N wastewater and greatly benefit the sustainable development of environmentally friendly biotechnologies for advanced nitrogen control.
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Affiliation(s)
- Suyan Pang
- Key Laboratory of Songliao Aquatic Environment, School of Municipal and Environmental Engineering, Ministry of Education, Jilin Jianzhu University, Changchun, China
| | - Ning Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
- Guangdong Provincial Engineering Technology Research Center for Life and Health of River & Lake, Pearl River Water Resources Research Institute, Pearl River Water Resources Commission of the Ministry of Water Resources, Guangzhou, China
- *Correspondence: Ning Li, ;
| | - Huan Luo
- Guangdong Provincial Engineering Technology Research Center for Life and Health of River & Lake, Pearl River Water Resources Research Institute, Pearl River Water Resources Commission of the Ministry of Water Resources, Guangzhou, China
| | - Xiaonan Luo
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Tong Shen
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
| | - Yanan Yang
- Guangdong Provincial Engineering Technology Research Center for Life and Health of River & Lake, Pearl River Water Resources Research Institute, Pearl River Water Resources Commission of the Ministry of Water Resources, Guangzhou, China
| | - Jin Jiang
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou, China
- Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou, China
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3
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Yang Y, Zhang C, Huang X, Gui X, Luo Y, Li Z. Exogenous Fe 2+ alleviated the toxicity of CuO nanoparticles on Pseudomonas tolaasii Y-11 under different nitrogen sources. PeerJ 2020; 8:e10351. [PMID: 33240659 PMCID: PMC7664463 DOI: 10.7717/peerj.10351] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2020] [Accepted: 10/21/2020] [Indexed: 01/17/2023] Open
Abstract
Extensive use of CuO nanoparticles (CuO-NPs ) inevitably leads to their accumulation in wastewater and toxicity to microorganisms that effectively treat nitrogen pollution. Due to the effects of different mediums, the sources of CuO-NPs-induced toxicity to microorganisms and methods to mitigating the toxicity are still unclear. In this study, CuO-NPs were found to impact the nitrate reduction of Pseudomonas tolaasii Y-11 mainly through the action of NPs themselves while inhibiting the ammonium transformation of strain Y-11 through releasing Cu2+. As the content of CuO-NPs increased from 0 to 20 mg/L, the removal efficiency of NO3− and NH4+ decreased from 42.29% and 29.83% to 2.05% and 2.33%, respectively. Exogenous Fe2+ significantly promoted the aggregation of CuO-NPs, reduced the possibility of contact with bacteria, and slowed down the damage of CuO-NPs to strain Y-11. When 0.01 mol/L Fe2+ was added to 0, 1, 5, 10 and 20 mg/L CuO-NPs treatment, the removal efficiencies of NO3- were 69.77%, 88.93%, 80.51%, 36.17% and 2.47%, respectively; the removal efficiencies of NH4+ were 55.95%, 96.71%, 38.11%, 20.71% and 7.43%, respectively. This study provides a method for mitigating the toxicity of CuO-NPs on functional microorganisms.
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Affiliation(s)
- Yuran Yang
- Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing, China
| | - Can Zhang
- Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing, China
| | - Xuejiao Huang
- Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing, China
| | - Xuwei Gui
- Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing, China
| | - Yifang Luo
- Chongqing Key Laboratory of Plant Disease Biology, College of Plant Protection, Southwest University, Chongqing, China
| | - Zhenlun Li
- Chongqing Key Laboratory of Soil Multi-Scale Interfacial Process, College of Resources and Environment, Southwest University, Chongqing, China
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Tang S, Liao Y, Xu Y, Dang Z, Zhu X, Ji G. Microbial coupling mechanisms of nitrogen removal in constructed wetlands: A review. BIORESOURCE TECHNOLOGY 2020; 314:123759. [PMID: 32654809 DOI: 10.1016/j.biortech.2020.123759] [Citation(s) in RCA: 68] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/01/2020] [Revised: 06/18/2020] [Accepted: 06/19/2020] [Indexed: 06/11/2023]
Abstract
Nitrogen removal through microorganisms is the most important pathway in constructed wetlands (CWs). In this review, we summarize the microbial coupling mechanisms of nitrogen removal, which are the common methods of nitrogen transformation. The electron pathways are shortened and consumption of oxygen and energy is reduced during the coupling of nitrogen transformation functional microorganisms. The highly efficient nitrogen removal mechanisms are cultivated from the design conditions in CWs, such as intermittent aeration and tidal flow. The coupling of microorganisms and substrates enhances nitrogen removal mainly by supplying electrons, and plants affect nitrogen transformation functional microorganisms by the release of oxygen and exudates from root systems as well as providing carriers for microbial attachment. In addition, inorganic elements such as Fe, S and H act as electron donors to drive the autotrophic denitrification process in CWs.
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Affiliation(s)
- Shuangyu Tang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Yinhao Liao
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Yichan Xu
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Zhengzhu Dang
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Xianfang Zhu
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China
| | - Guodong Ji
- Key Laboratory of Water and Sediment Sciences, Ministry of Education, Department of Environmental Engineering, Peking University, Beijing 100871, China.
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Tian T, Yu HQ. Denitrification with non-organic electron donor for treating low C/N ratio wastewaters. BIORESOURCE TECHNOLOGY 2020; 299:122686. [PMID: 31902635 DOI: 10.1016/j.biortech.2019.122686] [Citation(s) in RCA: 66] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/31/2019] [Revised: 12/21/2019] [Accepted: 12/23/2019] [Indexed: 05/21/2023]
Abstract
Denitrification with non-organic electron donors for treating low C/N ratio wastewater has attracted growing interests. Hydrogen, reduced sulfur compounds and ferrous ions are mainly used in autotrophic denitrification, holding promise for achieving practical applications. Recently, the development of autotrophic denitrification-based processes, such as bioelectrochemically-supported hydrogenotrophic denitrification and sulfur-/iron-based denitrification assisted multi-contaminant removal, provide opportunities for applying these processes in wastewater treatment. Exploration of the autotrophic denitrification process in terms of contaminant removal mechanism, interaction among functional microorganisms, and potential full-scale applications is thus of great importance. Here, an overview of the commonly used non-organic electron donors, e.g., hydrogen, reduced sulfur compounds and ferrous ions, in denitrification for treating low C/N ratio wastewater is provided. Also, the feasibility of applying the combined processes based on autotrophic denitrification with the compounds is discussed. Furthermore, challenges and future possibilities as well as concerns about the practical applications are envisaged in this review.
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Affiliation(s)
- Tian Tian
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Applied Chemistry, University of Science and Technology of China, Hefei 230026, China.
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Lu H, Li Y, Shan X, Abbas G, Zeng Z, Kang D, Wang Y, Zheng P, Zhang M. A holistic analysis of ANAMMOX process in response to salinity: From adaptation to collapse. Sep Purif Technol 2019. [DOI: 10.1016/j.seppur.2019.01.016] [Citation(s) in RCA: 48] [Impact Index Per Article: 9.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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He Z, Li Z, Zhang Q, Wei Z, Duo J, Pan X. Simultaneous remediation of As(III) and dibutyl phthalate (DBP) in soil by a manganese-oxidizing bacterium and its mechanisms. CHEMOSPHERE 2019; 220:837-844. [PMID: 30612053 DOI: 10.1016/j.chemosphere.2018.12.213] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/27/2018] [Revised: 12/13/2018] [Accepted: 12/31/2018] [Indexed: 05/26/2023]
Abstract
Soils are experiencing increasing pollution with arsenic (As) and phthalate esters (PAEs), which is threatening human health. In this study, the feasibility of simultaneous remediation of soil As(III) and a PAE, dibutyl phthalate (DBP), by a manganese-oxidizing bacterium (MnOB) was evaluated. As immobilization and DBP degradation were simultaneously enhanced by MnOB addition. The effects of initial concentrations of As(III), DBP, and Mn(II), and moisture content on the removal of As(III) and DBP were investigated. The results indicated that there was a competitive interaction between As(III) and DBP removal, and 40 mg/kg of Mn(II) dosage and 20%-30% soil moisture content were recommended for optimal and simultaneous removal of As(III) and DBP. Microbial community analysis revealed that community structure and diversity were not changed significantly by MnOB addition. Taken together, the findings from this study indicated that DBP was degraded primarily by microorganisms, whereas As(III) was removed largely by biogenic Mn oxides and immobilized by adsorption onto Mg/Fe oxides and/or formation of metal arsenate precipitates/co-precipitates. This study offers a novel and high-efficiency strategy to remediate the combined contamination of As and PAEs in soils.
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Affiliation(s)
- Zhanfei He
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Zeya Li
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Qingying Zhang
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Zhen Wei
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China
| | - Jia Duo
- Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China
| | - Xiangliang Pan
- Key Laboratory of Microbial Technology for Industrial Pollution Control of Zhejiang Province, College of Environment, Zhejiang University of Technology, Hangzhou, 310014, China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi, China.
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Wang H, Liang D, Wang YN, Sun Y, Li W, Zhang D, Tsang YF, Pan X. Fabricating biogenic Fe(III) flocs from municipal sewage sludge using NAFO processes: Characterization and arsenic removal ability. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 231:268-274. [PMID: 30347345 DOI: 10.1016/j.jenvman.2018.10.042] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/30/2017] [Revised: 07/11/2018] [Accepted: 10/13/2018] [Indexed: 06/08/2023]
Abstract
This study involved fabricating biogenic Fe(III) flocs enriched from municipal sludge using microbial nitrate-dependent anaerobic Fe(II)-oxidizing (NAFO) processes. The research focused on bacterial community compositions and physicochemical properties of the biogenic Fe(III) flocs and their ability to adsorb arsenic (As). High-throughput sequencing analysis showed that significant microbial succession occurs in the raw sludge after the NAFO processes. The predominant bacterial communities in the biogenic Fe(III) flocs included Rhodanobacter, Parvibaculum, Gemmatimonas and Segetibacter genera. Microscopic and spectroscopic analyses included scanning electron microscopy - energy disperse spectroscopy (SEM-EDS), X-ray diffraction (XRD), Fourier transform infrared spectroscopy (FTIR) and Raman spectroscopy. These tests indicated that biogenic Fe(III) flocs were a mixture of NAFO bacteria and nanosized, poorly crystalline Fe(III) oxide particles. Batch experiments showed that after 120 min of reaction time, more than 95% of As(III) and As(V) (at an initial concentrations of 0.25 mg/L) were effectively removed with 120 ppm biogenic Fe(III) flocs. In addition, biogenic Fe(III) flocs removed As more effectively than abiotic Fe(III) flocs. These findings indicated that biogenic Fe(III) flocs produced from municipal sludge using NAFO processes performed well in removing As.
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Affiliation(s)
- Huawei Wang
- College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China; Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China; Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, New Territories, Hong Kong, China
| | - Dandan Liang
- College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Ya-Nan Wang
- College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Yingjie Sun
- College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China.
| | - Weihua Li
- College of Environmental and Municipal Engineering, Qingdao University of Technology, Qingdao 266033, PR China
| | - Daoyong Zhang
- Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China
| | - Yiu Fai Tsang
- Department of Science and Environmental Studies, The Education University of Hong Kong, Tai Po, New Territories, Hong Kong, China.
| | - Xiangliang Pan
- Xinjiang Key Laboratory of Environmental Pollution and Bioremediation, Xinjiang Institute of Ecology and Geography, Chinese Academy of Sciences, Urumqi 830011, PR China
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Zhang Y, Douglas GB, Kaksonen AH, Cui L, Ye Z. Microbial reduction of nitrate in the presence of zero-valent iron. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 646:1195-1203. [PMID: 30235605 DOI: 10.1016/j.scitotenv.2018.07.112] [Citation(s) in RCA: 51] [Impact Index Per Article: 10.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/28/2018] [Revised: 07/09/2018] [Accepted: 07/09/2018] [Indexed: 06/08/2023]
Abstract
Microbial reduction of nitrate in the presence of zero-valent iron (ZVI) was evaluated in anoxic shake flasks to assess the feasibility of ZVI-facilitated biological nitrate removal. Nitrate was completely reduced within 3days in the presence of both ZVI and microorganisms (ZVI-M). In contrast, only 75% of the nitrate was reduced in the presence of ZVI but without microbial inoculum. Nitrate removal was affected by ZVI-M flasks initial pH, nitrate concentration and ZVI dosage. Nitrate removal in the inoculated ZVI flasks system could be divided into two phases: adaptation phase and log phase which could be described by first-order kinetic equations. The analysis of bacterial communities in the inoculated flasks in the absence and presence of ZVI, indicated that the addition of ZVI increased the relative abundance of Methylotenera spp., Alcaligenes eutrophus, Pseudomonas spp. which might play an important role in nitrogen removal. The presence of ZVI could enhance biological denitrification through four mechanisms: the biological reduction of nitrate with 1) electrons derived directly from ZVI; 2) with hydrogen released from ZVI; 3) with Fe2+ released from ZVI; and 4) with acetate generated by homoacetogens which utilize H2 released from ZVI.
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Affiliation(s)
- Yiping Zhang
- Department of Environmental Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China
| | - Grant B Douglas
- CSIRO Land and Water, Centre for Environment and Life Sciences, Private Bag 5, Wembley, 6913, WA, Australia
| | - Anna H Kaksonen
- CSIRO Land and Water, Centre for Environment and Life Sciences, Private Bag 5, Wembley, 6913, WA, Australia
| | - Lili Cui
- Hebei Energy and Environmental Engineering, Hebei Institute of Architectural Engineering, Zhangjiakou, Hebei 075000, China
| | - Zhengfang Ye
- Department of Environmental Engineering, Peking University, The Key Laboratory of Water and Sediment Sciences, Ministry of Education, Beijing 100871, China.
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Liu Y, Feng C, Sheng Y, Dong S, Chen N, Hao C. Effect of Fe(II) on reactivity of heterotrophic denitrifiers in the remediation of nitrate- and Fe(II)-contaminated groundwater. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2018; 166:437-445. [PMID: 30292110 DOI: 10.1016/j.ecoenv.2018.09.104] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/22/2018] [Revised: 09/07/2018] [Accepted: 09/24/2018] [Indexed: 06/08/2023]
Abstract
Heterotrophic denitrifiers, capable of simultaneous nitrate reduction and Fe(II) oxidation, can be applied for the remediation of nitrate and Fe(II) combined contamination in groundwater. Under strictly anaerobic condition, denitrifying microbial communities were enriched with the coexistence of soluble nitrate, Fe(II) and associated nutrient elements to monitor the denitrification process. Low abundance of Fe(II) (e.g., 10 mg L-1 in this study) tended to stimulate the activity of denitrifying microbial communities. However, elevated Fe(II) concentration (50 and 100 mg L-1 in this study), acted as a stress, strongly inhibited the activity and reproduction of denitrifiers. Besides, through thermodynamics calculations, methanol rather than Fe(II) was proved to be the preferable electron donors for both energy metabolism and anabolism. Betaproteobacteria was found to be the most predominant (sub)phylum in all enriched microbial assemblages. Methylovesartilis was the most predominant group mainly catalyzed for methanol based denitrification, and others denitrifiers included Methylophilaceae, Dechloromonas and Denitratisoma. Excessive Fe(II) in the solution greatly reduced the proportions of these denitrifying groups, while the influence seemed to be less apparent on functional genes composition. As such, a conceptional metabolism pathway of the most dominant genus (i.e., Methylovesartilis) for nitrate reducing as well as methanol and Fe(II) oxidation confirmed that biotic nitrate reducing and Fe(II) oxidizing were potentially proceeded in cytoplasm by enzymes such as NarGHI. The Fe(II) oxidation rate depended on the rate of Fe(II) entering into the cell. These findings provide a clear mechanistic understanding of heterotrophic denitrification coupling with Fe(II) oxidation, and environmental implication for the bioremediation of nitrate and Fe(II) contaminated groundwater.
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Affiliation(s)
- Ying Liu
- Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China
| | - Chuanping Feng
- Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China.
| | - Yizhi Sheng
- School of Environment, Tsinghua University, Beijing 100084, China
| | - Shanshan Dong
- Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China
| | - Nan Chen
- Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China
| | - Chunbo Hao
- Key Laboratory of Groundwater Circulation and Environmental Evolution (China University of Geosciences (Beijing)), Ministry of Education, Beijing 100083, China; School of Water Resources and Environment, China University of Geosciences, Beijing 100083, China
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