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Han Z, Hu R, Zheng X, Zhao Z, Li W, He H, Lin T, Xu H. Feasibility of simultaneous optimization of Anammox start-up and nitrogen removal performance by intermittent dosing of nanoscale zero-valent iron. BIORESOURCE TECHNOLOGY 2024; 408:131140. [PMID: 39069140 DOI: 10.1016/j.biortech.2024.131140] [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: 05/15/2024] [Revised: 07/06/2024] [Accepted: 07/19/2024] [Indexed: 07/30/2024]
Abstract
The long acclimation period and sensitivity to environmental conditions of Anammox are the bottlenecks for its promotion and application. An innovative strategy was adopted to accelerate functional microbial enhancement and improve nitrogen removal performance by inoculating cryopreserved Anammox sludge and activated sludge with intermittent dosing of nanoscale zero-valent iron (nZVI). The acclimation time was shortened by 76 days with nitrogen removal efficiency (NRE) reaching up to 91.07 %. Anammox, NDFO (nitrate/nitrite-dependent Fe(II) oxidation), Feammox (Fe(III) reduction coupled with anaerobic ammonium oxidation) and abiotic reactions were coupled in the system with nZVI, contributing to 69.79 %, 15.14 %, 9.84 % and 0.25 % of nitrogen removal, respectively. Further microbial analysis demonstrated significant enrichment of functional microorganisms, such as Candidatus Jettenia, Acidovorax and Comamonas. High-efficient nitrogen removal was attribute to the increase of functional genes involved in Anammox, electronic transfer, heme C synthesis and iron metabolism. This work provides an inspiring idea for the mainstream Anammox application.
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Affiliation(s)
- Zongshuo Han
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Ruijie Hu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Xiaoying Zheng
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China.
| | - Zhilin Zhao
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Wenfei Li
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Haidong He
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Tao Lin
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
| | - Hang Xu
- Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; College of Environment, Hohai University, Nanjing 210098, PR China
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Zhu X, Zhang X, Gao B, Ji L, Zhao R, Wu P. A critical review of Mnammox coupled with the NDMO for innovative nitrogen removal. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 951:175453. [PMID: 39137844 DOI: 10.1016/j.scitotenv.2024.175453] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/18/2024] [Revised: 08/08/2024] [Accepted: 08/09/2024] [Indexed: 08/15/2024]
Abstract
In the context of increasing global nitrogen pollution, traditional biological nitrogen removal technologies like nitrification and denitrification are hindered by high energy consumption. Additionally, the deployment of anaerobic ammonium oxidation (Anammox) technology is constrained due to the slow growth rate of Anammox bacteria and there is a bottleneck in nitrogen removal efficiency. To overcome these technical bottlenecks, researchers have discovered a revolutionary nitrogen removal technology that cleverly combines the redox cycling of manganese with nitrification and denitrification reactions. In this new process, manganese dependent anaerobic ammonium oxidation (Mnammox) bacteria can convert NH4+ to N2 under anaerobic conditions, while nitrate/nitrite dependent manganese oxidation (NDMO) bacteria use NO3-/NO2- as electron acceptors to oxidize Mn2+ to Mn4+. Mn4+ acts as an electron acceptor in Mnammox reaction, thereby realizing the autotrophic nitrogen removal process. This innovative method not only simplifies the steps of biological denitrification, but also significantly reduces the consumption of oxygen and organic carbon, providing a more efficient and environmentally friendly solution to the problem of nitrogen pollution. The article initially provides a concise overview of prevalent nitrogen removal technologies and the application of manganese in these processes, and discusses the role of manganese in biogeochemical cycles, including its discovery, mechanism of action, microbial communities involved, and its impact on these key factors in the process. Subsequently, metabolic principles, benefits, advantages, and environmental considerations of Mnammox coupled with the NDMO process are analyzed in detail. Finally, this article summarizes the shortcomings of current research and looks forward to future research directions. The goal of this article is to provide a valuable reference for researchers to fully understand the application of manganese in nitrogen removal processes.
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Affiliation(s)
- Xurui Zhu
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Xiaonong Zhang
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Bo Gao
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Luomiao Ji
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Rui Zhao
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China
| | - Peng Wu
- National and Local Joint Engineering Laboratory of Municipal Sewage Resource Utilization Technology, Jiangsu Collaborative Innovation Center of Technology and Material of Water Treatment, School of Environmental Science and Engineering, Suzhou University of Science and Technology, Suzhou 215009, China.
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Liu Y, Song X, Hou X, Wang Y, Cao X. Effect of Mn-HA on ARGs and MRGs in nitrogen-culturing sludge. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2024; 365:121615. [PMID: 38936019 DOI: 10.1016/j.jenvman.2024.121615] [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: 03/09/2024] [Revised: 06/21/2024] [Accepted: 06/23/2024] [Indexed: 06/29/2024]
Abstract
The simultaneous escalation in ARGs (antibiotic resistance genes) and MRGs (metal resistance genes) further complicates the intricate network of factors contributing to the proliferation of microbial resistance. Manganese, which has been reported to affect the resistance of bacteria to antibiotics and metals, plays a vital role in microbial nitrogen metabolism. Moreover, nitrifying and denitrifying populations are potential hosts for ARGs. In this study, manganese was introduced in its prevalent organic chelated form in the environment (Manganese humus chelates, Mn-HA) to a N metabolism sludge to explore the effect of manganese on MRGs and ARGs dissemination. Metagenomics results revealed that manganese availability enhances nitrogen metabolism, while a decrease in ARGs was noted which may be attributed to the inhibition of horizontal gene transfer (HGT), reflected in the reduced integrase -encoded gene int. Population analysis revealed that nitrifier and denitrifier genus harbor MRGs and ARGs, indicating that nitrifier and denitrifier are hosts of MRGs and ARGs. This raises the question of whether the prevalence of ARGs is always increased in metal-contained environments.
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Affiliation(s)
- Yingying Liu
- College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai, 201620, China
| | - Xinshan Song
- College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai, 201620, China.
| | - Xiaoxiao Hou
- College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai, 201620, China
| | - Yuhui Wang
- College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai, 201620, China
| | - Xin Cao
- College of Environmental Science and Engineering, State Environmental Protection Engineering Center for Pollution Treatment and Control in Textile Industry, Donghua University, Shanghai, 201620, China
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Gu J, Cao Y, Sun Q, Zhang J, Xu Y, Jin H, Huang H. The bacterial community drive the humification and greenhouse gas emissions during plant residues composting under different aeration rates. ENVIRONMENTAL TECHNOLOGY 2024:1-15. [PMID: 38920117 DOI: 10.1080/09593330.2024.2369732] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/02/2024] [Accepted: 05/16/2024] [Indexed: 06/27/2024]
Abstract
This study investigated the effects of different aeration intensities on organic matter (OM) degradation, greenhouse gas emissions (GHG) as well as humification during plant residue composting. Three intermittent aeration intensities of 0.084 (Tlow), 0.19 (Tmedium) and 0.34 (Thigh) L min-1kg-1 DM with 30 min on/30 min off were conducted on a lab-scale composting experiment. Results showed that OM mineralization in Thigh was more evident than Tlow and Tmedium, resulting in the highest humic acid content. Humic acid content in Tmedium and Thigh was 15.7% and 18.5% higher than that in Tlow. The average O2 concentration was 4.9%, 9.5% and 13.6% for Tlow, Tmedium and Thigh. Compared with Tmedium and Thigh, Tlow reduced CO2 and N2O emissions by 18.3%-39.6% and 72.4%-63.9%, but the CH4 emission was highest in Tlow. But the total GHG emission was the lowest in Thigh. Linear Discriminant Analysis Effect Size analysis showed that the core bacteria within Tlow mainly belonged to Anaerolineaceae, which was significantly negatively correlated to the emission of CH4. Thermostaphylospora, Unclassified_Vicinamibacteraceae and Sulfurifustis were identified as core bacteria in Tmedium and Thigh, and these genus were significantly postively correlated to CO2 and N2O emissions. Redundancy analysis showed that total orgnic carbon, O2 and electrical conductivity were the key factors affecting the evolution of bacterial community.
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Affiliation(s)
- Junyu Gu
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- College of Resources and Environmental Sciences, Nanjing, People's Republic of China
| | - Yun Cao
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- College of Resources and Environmental Sciences, Nanjing, People's Republic of China
- Key Laboratory of Crop and Livestock Integrated Farming, Ministry of Agriculture, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
| | - Qian Sun
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Key Laboratory of Crop and Livestock Integrated Farming, Ministry of Agriculture, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
| | - Jing Zhang
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
| | - Yueding Xu
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
| | - Hongmei Jin
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- College of Resources and Environmental Sciences, Nanjing, People's Republic of China
- Key Laboratory of Crop and Livestock Integrated Farming, Ministry of Agriculture, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
| | - Hongying Huang
- Institute of Agricultural Resources and Environment, Jiangsu Academy of Agricultural Sciences, Nanjing, People's Republic of China
- Jiangsu Collaborative Innovation Center for Solid Organic Waste Resource Utilization, Nanjing, People's Republic of China
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Guo J, Yang H, Wang C, Liu Z, Huang Y, Zhang C, Huang Q, Xue W, Sun Y. Inhibitory effects of Pseudomonas sp. W112 on cadmium accumulation in wheat grains: Reduced the bioavailability in soil and enhanced the interception by plant organs. CHEMOSPHERE 2024; 355:141828. [PMID: 38552800 DOI: 10.1016/j.chemosphere.2024.141828] [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: 03/07/2024] [Accepted: 03/26/2024] [Indexed: 04/01/2024]
Abstract
Microorganisms play an important role in heavy metal bioremediation and soil fertility. The effects of soil inoculation with Pseudomonas sp. W112 on Cd accumulation in wheat were investigated by analyzing the transport, subcellular distribution and speciation of Cd in the soil and plants. Pseudomonas sp. W112 application significantly decreased Cd content in the roots, internode and grains by 10.2%, 29.5% and 33.0%, respectively, and decreased Cd transfer from the basal nodes to internodes by 63.5%. Treatment with strain W112 decreased the inorganic and water-soluble Cd content in the roots and increased the proportion of residual Cd in both the roots and basal nodes. At the subcellular level, the Cd content in the root cell wall and basal node cytosol increased by 19.6% and 61.8%, respectively, indicating that strain W112 improved the ability of the root cell wall and basal node cytosol to fix Cd. In the rhizosphere soil, strain W112 effectively colonized and significantly decreased the exchangeable Cd, carbonate-bound Cd and iron-manganese oxide-bound Cd content by 43.5%, 27.3% and 17.6%, respectively, while it increased the proportion of residual Cd by up to 65.2%. Moreover, a 3.1% and 23.5% increase in the pH and inorganic nitrogen content in the rhizosphere soil, respectively, was recorded. Similarly, soil bacterial community sequencing revealed that inoculating with strain W112 increased the abundance of Pseudomonas, Thauera and Azoarcus, which are associated with inorganic nitrogen metabolism, and decreased that of Acidobacteria, which is indicative of soil alkalinization. Hence, root application of Pseudomonas sp. W112 improved soil nitrogen availability and inhibited Cd accumulation in the wheat grains in a two-stage process: by reducing the Cd availability in the rhizosphere soil and by improving Cd interception and fixation in the wheat roots and basal nodes. Pseudomonas sp. W112 may be a suitable bioremediation agent for restoring Cd-contaminated wheat fields.
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Affiliation(s)
- Jiajia Guo
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China; Centre for Green Agricultural Inputs and MicroEcological Farming, Jinhe Jiannong (Beijing) Agricultural Biotechnology Co., Ltd., Chinese Academy of Agricultural Sciences, Beijing, 100020, People's Republic of China.
| | - Hao Yang
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China; College of Resources and Environment, Northeast Agricultural University, Harbin, 1500302, People's Republic of China.
| | - Changrong Wang
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Zhongqi Liu
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Yongchun Huang
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Changbo Zhang
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Qingqing Huang
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Weijie Xue
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
| | - Yuebing Sun
- Key Laboratory of Original Agro-Environmental Pollution Prevention and Control, Agro-Environmental Protection Institute, Ministry of Agriculture and Rural Affairs, Tianjin, 300191, People's Republic of China.
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Costa L, Martinez M, Suleiman M, Keiser R, Lehmann M, Lenz M. Manganese reductive dissolution coupled to Sb mobilization in contaminated shooting range soil. Appl Microbiol Biotechnol 2024; 108:295. [PMID: 38598118 PMCID: PMC11006745 DOI: 10.1007/s00253-024-13133-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/22/2024] [Revised: 03/14/2024] [Accepted: 03/26/2024] [Indexed: 04/11/2024]
Abstract
A "redox-stat" RMnR bioreactor was employed to simulate moderately reducing conditions (+ 420 mV) in Sb-contaminated shooting range soils for approximately 3 months, thermodynamically favoring Mn(IV) reduction. The impact of moderately reducing conditions on elemental mobilization (Mn, Sb, Fe) and speciation [Sb(III) versus Sb(V); Fe2+/Fe3+] was compared to a control bioreactor RCTRL without a fixed redox potential. In both bioreactors, reducing conditions were accompanied by an increase in effluent Sb(V) and Mn(II) concentrations, suggesting that Sb(V) was released through microbial reduction of Mn oxyhydroxide minerals. This was underlined by multiple linear regression analysis showing a significant (p < 0.05) relationship between Mn and Sb effluent concentrations. Mn concentration was the sole variable exhibiting a statistically significant effect on Sb in RMnR, while under the more reducing conditions in RCTRL, pH and redox potential were also significant. Analysis of the bacterial community composition revealed an increase in the genera Azoarcus, Flavisolibacter, Luteimonas, and Mesorhizobium concerning the initial soil, some of which are possible key players in the process of Sb mobilization. The overall amount of Sb released in the RMnR (10.40%) was virtually the same as in the RCTRL (10.37%), which underlines a subordinate role of anoxic processes, such as Fe-reductive dissolution, in Sb mobilization. This research underscores the central role of relatively low concentrations of Mn oxyhydroxides in influencing the fate of trace elements. Our study also demonstrates that bioreactors operated as redox-stats represent versatile tools that allow quantifying the contribution of specific mechanisms determining the fate of trace elements in contaminated soils. KEY POINTS: • "Redox-stat" reactors elucidate Sb mobilization mechanisms • Mn oxyhydroxides microbial reductive dissolution has a major role in Sb mobilization in soils under moderately reducing conditions • Despite aging the soil exhibited significant Sb mobilization potential, emphasizing persistent environmental effects.
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Affiliation(s)
- Lara Costa
- Institute for Ecopreneurship, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Hofackerstrasse 30, 4132, Muttenz, Switzerland.
- Department of Environmental Science, University of Basel, Bernoullistrasse 30, 4056, Basel, Switzerland.
| | - Mathieu Martinez
- Institute for Ecopreneurship, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Hofackerstrasse 30, 4132, Muttenz, Switzerland
| | - Marcel Suleiman
- Institute for Ecopreneurship, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Hofackerstrasse 30, 4132, Muttenz, Switzerland
| | - Rolf Keiser
- ARMASUISSE Competence Center Soil, Guisanplatz 1, 3003, Bern, Switzerland
| | - Moritz Lehmann
- Department of Environmental Science, University of Basel, Bernoullistrasse 30, 4056, Basel, Switzerland
| | - Markus Lenz
- Institute for Ecopreneurship, School of Life Science, University of Applied Sciences and Arts Northwestern Switzerland (FHNW), Hofackerstrasse 30, 4132, Muttenz, Switzerland
- Sub-Department of Environmental Technology, Wageningen University, 6700 EV, Wageningen, The Netherlands
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Jiang Z, Huang X, Wang S, Xiong J, Xie C, Chen Y. Divalent manganese stimulates the removal of nitrate by anaerobic sludge. RSC Adv 2024; 14:2447-2452. [PMID: 38223698 PMCID: PMC10784783 DOI: 10.1039/d3ra07088c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/18/2023] [Accepted: 01/07/2024] [Indexed: 01/16/2024] Open
Abstract
This study investigated the effect of different concentrations of Mn2+ on the removal of nitrate by anaerobic sludge and changes in the microbial communities through batch experiments. The results showed that the addition of Mn2+ promoted nitrate removal by anaerobic sludge; the nitrate was completely removed within 6 d in the treatment group with >5 mM Mn2+. With the increase in Mn2+, the concentration of nitrite and nitrous oxide increased in the first 4 d and then decreased to 0 μM after 8 d of incubation. The increasing tendency of ammonium increased firstly and then decreased with the addition of Mn2+ compared to A. Moreover, the Mn2+ removal efficiency gradually decreased with the increase of Mn2+ concentration. The changes of microflora structure in sludge before and after adding Mn2+ were analyzed, and the results revealed that the microbial communities in the sludge may have evolved towards an energy-efficient association of short-cut nitrification, denitrification, and anaerobic ammonia oxidation after adding Mn2+. Mn2+ stimulated the removal of nitrate by anaerobic sludge mainly by promoting the growth of PHOS-HE36.
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Affiliation(s)
- Zhaojie Jiang
- School of Resources, Environment and Materials, Guangxi University Nanning 530004 China
| | - Xuejiao Huang
- Guangxi Key Laboratory of Agro-Environment and Agro-Product Safety, College of Agriculture, Guangxi University Nanning Guangxi 530004 +86 18577976592
- Guangxi Bossco Environmental Protection Technology Co., Ltd. Nanning 530007 Guangxi China
| | - Shuangfei Wang
- College of Light Industry and Food Engineering, Guangxi University Nanning Guangxi 530004 China
| | - Jianhua Xiong
- School of Resources, Environment and Materials, Guangxi University Nanning 530004 China
- Guangxi Bossco Environmental Protection Technology Co., Ltd. Nanning 530007 Guangxi China
| | - Chunmin Xie
- Guangxi Bossco Environmental Protection Technology Co., Ltd. Nanning 530007 Guangxi China
| | - Yongli Chen
- Guangxi Bossco Environmental Protection Technology Co., Ltd. Nanning 530007 Guangxi China
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