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Wang Q, Zhang C, Song J, Bamanu B, Zhao Y. Inhibitory mechanism of Cr(VI) on sulfur-based denitrification: Bio-toxicity, bio-electron characteristics, and microbial evolution. JOURNAL OF HAZARDOUS MATERIALS 2024; 472:134447. [PMID: 38692000 DOI: 10.1016/j.jhazmat.2024.134447] [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: 02/09/2024] [Revised: 03/24/2024] [Accepted: 04/25/2024] [Indexed: 05/03/2024]
Abstract
Sulfur-based denitrification is a promising technology for efficient nitrogen removal in low-carbon wastewater, while it is easily affected by toxic substances. This study revealed the inhibitory mechanism of Cr(VI) on thiosulfate-based denitrification, including bio-toxicity and bio-electron characteristics response. The activity of nitrite reductase (NIR) was more sensitive to Cr(VI) than that of nitrate reductase (NAR), and NIR was inhibited by 21.32 % and 19.86 % under 5 and 10 mg/L Cr(VI), resulting in 10.12 and 15.62 mg/L of NO2--N accumulation. The biofilm intercepted 36.57 % of chromium extracellularly by increasing 25.78 % of extracellular polymeric substances, thereby protecting microbes from bio-toxicity under 5 mg/L Cr(VI). However, it was unable to resist 20-30 mg/L of Cr(VI) bio-toxicity as 19.95 and 14.29 mg Cr/(g volatile suspended solids) invaded intracellularly, inducing the accumulation of reactive oxygen species by 165.98 % and 169.12 %, which triggered microbial oxidative-stress and damaged the cells. In terms of electron transfer, S2O32- oxidation was inhibited, and parts of electrons were redirected intracellularly to maintain microbial activity, resulting in insufficient electron donors. Meanwhile, the contents of flavin adenine dinucleotide and cytochrome c decreased under 5-30 mg/L Cr(VI), reducing the electron acquisition rate of denitrification. Thermomonas (the dominant genus) possessed denitrification and Cr(VI) resistance abilities, playing an important role in antioxidant stress and biofilm formation. ENVIRONMENTAL IMPLICATION: Sulfur-based denitrification (SBD) is a promising method for nitrate removal in low-carbon wastewater, while toxic heavy metals such as Cr(VI) negatively impair denitrification. This study elucidated Cr(VI) inhibitory mechanisms on SBD, including bio-toxicity response, bio-electron characteristics, and microbial community structure. Higher concentrations Cr(VI) led to intracellular invasion and oxidative stress, evidenced by ROS accumulation. Moreover, Cr(VI) disrupted electron flow by inhibiting thiosulfate oxidation and affecting electron acquisition by denitrifying enzymes. This study provided valuable insights into Cr(VI) toxicity, which is of great significance for improving wastewater treatment technologies and maintaining efficient and stable operation of SBD in the face of complex environmental challenges.
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Affiliation(s)
- Qian Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Chenggong Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jinxin Song
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Bibek Bamanu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China.
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2
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Xu H, Zhang H, Qin C, Li X, Xu D, Zhao Y. Groundwater Cr(VI) contamination and remediation: A review from 1999 to 2022. CHEMOSPHERE 2024; 360:142395. [PMID: 38797207 DOI: 10.1016/j.chemosphere.2024.142395] [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: 09/09/2023] [Revised: 05/13/2024] [Accepted: 05/20/2024] [Indexed: 05/29/2024]
Abstract
Hexavalent chromium (Cr(VI)) contamination of groundwater has traditionally been an environmental issue of great concern due to its bioaccumulative and highly toxic nature. This paper presents a review and bibliometric analysis of the literature on the interest area "Cr(VI) in groundwater" published in the Web of Science Core Collection from 1999 to 2022. First, information on 203 actual Cr(VI)-contaminated groundwater sites around the world was summarized, and the basic characteristics of the sources and concentrations of contamination were derived. 68.95% of the sites were due to human causes and 56.43% of these sites had Cr(VI) concentrations in the range of 0-10 mg/L. At groundwater sites with high Cr(VI) contamination due to natural causes, 75.00% of the sites had Cr(VI) concentrations less than 0.2 mg/L. A total of 936 papers on "Cr(VI) in groundwater" were retrieved for bibliometric analysis: interest in research on Cr(VI) in groundwater has grown rapidly in recent years; 59.4% of the papers were published in the field of environmental sciences. A systematic review of the progress of studies on the Cr(VI) removal/remediation based on reduction, adsorption and biological processes is presented. Out of 666 papers on Cr(VI) removal/remediation, 512, 274, and 75 papers dealt with the topics of reduction, adsorption, and bioremediation, respectively. In addition, several studies have demonstrated the potential applicability of natural attenuation in the remediation of Cr(VI)-contaminated groundwater. This paper will help researchers to understand and investigate methodological strategies to remove Cr(VI) from groundwater in a more targeted and effective manner.
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Affiliation(s)
- Huichao Xu
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Hui Zhang
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Chuanyu Qin
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Xiaoyu Li
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Dan Xu
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China
| | - Yongsheng Zhao
- Key Laboratory of Groundwater Resources and Environment of Ministry of Education, College of New Energy and Environment, Jilin University, Changchun, 130021, China; National and Local Joint Engineering Laboratory for Petrochemical Contaminated Site Control and Remediation Technology, Jilin University, Changchun, 130021, China; Jilin Provincial Key Laboratory of Water Resources and Environment, College of New Energy and Environment, Jilin University, Changchun, 130021, China.
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3
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Niu C, Zhao X, Shi D, Ying Y, Wu M, Lai CY, Guo J, Hu S, Liu T. Bioreduction of chromate in a syngas-based membrane biofilm reactor. JOURNAL OF HAZARDOUS MATERIALS 2024; 470:134195. [PMID: 38581872 DOI: 10.1016/j.jhazmat.2024.134195] [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: 01/02/2024] [Revised: 03/07/2024] [Accepted: 03/31/2024] [Indexed: 04/08/2024]
Abstract
This study leveraged synthesis gas (syngas), a renewable resource attainable through the gasification of biowaste, to achieve efficient chromate removal from water. To enhance syngas transfer efficiency, a membrane biofilm reactor (MBfR) was employed. Long-term reactor operation showed a stable and high-level chromate removal efficiency > 95%, yielding harmless Cr(III) precipitates, as visualised by scanning electron microscopy and energy dispersive X-ray analysis. Corresponding to the short hydraulic retention time of 0.25 days, a high chromate removal rate of 80 µmol/L/d was attained. In addition to chromate reduction, in situ production of volatile fatty acids (VFAs) by gas fermentation was observed. Three sets of in situ batch tests and two groups of ex situ batch tests jointly unravelled the mechanisms, showing that biological chromate reduction was primarily driven by VFAs produced from in situ syngas fermentation, whereas hydrogen originally present in the syngas played a minor role. 16 S rRNA gene amplicon sequencing has confirmed the enrichment of syngas-fermenting bacteria (such as Sporomusa), who performed in situ gas fermentation leading to the synthesis of VFAs, and organics-utilising bacteria (such as Aquitalea), who utilised VFAs to drive chromate reduction. These findings, combined with batch assays, elucidate the pathways orchestrating synergistic interactions between fermentative microbial cohorts and chromate-reducing microorganisms. The findings facilitate the development of cost-effective strategies for groundwater and drinking water remediation and present an alternative application scenario for syngas.
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Affiliation(s)
- Chenkai Niu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Xinyu Zhao
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Danting Shi
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077, Hong Kong Special Administrative Region of China
| | - Yifeng Ying
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Mengxiong Wu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Chun-Yu Lai
- College of Environmental and Resource Science, Zhejiang University, Hangzhou, Zhejiang 310058, China
| | - Jianhua Guo
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Shihu Hu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia
| | - Tao Liu
- Australian Centre for Water and Environmental Biotechnology (ACWEB, formerly AWMC), The University of Queensland, St. Lucia, Queensland 4072, Australia; Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, 999077, Hong Kong Special Administrative Region of China.
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Wang Q, Zhang C, Song J, Bamanu B, Zhao Y. Enhancement of bio-promoters on hexavalent chromium inhibited sulfur-driven denitrification: repairing damage, accelerating electron transfer, and reshaping microbial collaboration. BIORESOURCE TECHNOLOGY 2024; 400:130699. [PMID: 38615966 DOI: 10.1016/j.biortech.2024.130699] [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: 01/27/2024] [Revised: 03/13/2024] [Accepted: 04/12/2024] [Indexed: 04/16/2024]
Abstract
Proposing recovery strategies to recover heavy-metal-inhibited sulfur-driven denitrification, as well as disclosing recovery mechanisms, can provide technical support for the stable operation of bio-systems. This study proposed an effective bio-promoter (mediator-promoter composed of L-cysteine, biotin, cytokinin, and anthraquinone-2,6-disulfonate) to recover Cr(VI) inhibited sulfur-driven denitrification, which effectively reduced the recovery time of NO3--N reduction (18-21 cycles) and NO2--N reduction (27-42 cycles) compared with self-recovery. The mediator-promoter repaired microbial damage by promoting intracellular chromium efflux. Moreover, the mediator-promoter reduced the accumulated reactive oxygen species by stimulating the secretion of antioxidant enzymes, reaching equilibrium in the oxidative-antioxidant system. To improve electron transmission, the mediator-promoter restored S2O32- oxidation to provide adequate electron donors and increased electron transfer rate by increasing cytochrome c levels. Mediator-promoter boosted the abundance of Thiobacillus (sulfur-oxidizing bacterium) and Simplicispira (denitrifying bacterium), which were positively correlated, facilitating the rapid denitrification recovery and the long-term stable operation of recovered systems.
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Affiliation(s)
- Qian Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Chenggong Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jinxin Song
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Bibek Bamanu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China.
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5
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Li X, Zhao J, Lu Z, Zhou J, Zhang W, Hu B. Role of sulfide on DNRA distribution and the microbial community structure in a sulfide-driven nitrate reduction process. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2024; 31:28803-28813. [PMID: 38564127 DOI: 10.1007/s11356-024-32912-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: 08/11/2023] [Accepted: 03/11/2024] [Indexed: 04/04/2024]
Abstract
Microbial nitrate reduction processes involve two competing pathways: denitrification (DEN) and dissimilatory nitrate reduction to ammonium (DNRA). This study investigated the distribution of DNRA in a sole sulfur-driven nitrogen conversion process using a laboratory-scale sequencing biofilm batch reactor (SBBR) through a series of batch tests with varying sulfide/nitrate (S/N) ratios. The results showed that DNRA became more dominant in the sulfide-oxidizing autotrophic denitrification (SOAD) process as the S/N ratio increased to 1.5:1, 1.7:1, and 2:1, reaching a peak of 35.3% at the S/N ratio of 1.5:1. Oxidation-reduction potential (ORP) patterns demonstrated distinct inflection points for nitrate and nitrite consumption under the SOAD-only conditions, whereas these points overlapped when DNRA coexisted with SOAD. Analysis of 16S ribosomal RNA identified Ignavibacterium, Hydrogenophaga, and Geobacter as the dominant genera responsible for DNRA during autotrophic nitrate reduction. The findings of the DNRA divergence investigation provided valuable insights into enhancing biological nitrogen removal processes, particularly when coupled with the anammox.
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Affiliation(s)
- Xiaoling Li
- Key Laboratory of Water Supply & Sewage Engineering, Ministry of Housing and Urban-Rural Development, School of Civil Engineering, Chang'an University, Xi'an, 710054, China
| | - Jianqiang Zhao
- School of Water and Environment, Chang'an University, Xi'an, 710064, China.
| | - Zhaolin Lu
- Southwest Municipal Engineering Design & Research Institute of China, Chengdu, 610084, China
| | - Juncai Zhou
- Key Laboratory of Water Supply & Sewage Engineering, Ministry of Housing and Urban-Rural Development, School of Civil Engineering, Chang'an University, Xi'an, 710054, China
| | - Wenbo Zhang
- Key Laboratory of Water Supply & Sewage Engineering, Ministry of Housing and Urban-Rural Development, School of Civil Engineering, Chang'an University, Xi'an, 710054, China
| | - Bo Hu
- Key Laboratory of Water Supply & Sewage Engineering, Ministry of Housing and Urban-Rural Development, School of Civil Engineering, Chang'an University, Xi'an, 710054, China
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6
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Gong Q, Zeng W, Ma B, Hao X, Zhan M, Peng Y. Ultra-stable mixotrophic denitrification coupled with anammox under organic stress for mainstream municipal wastewater treatment. WATER RESEARCH 2024; 249:120932. [PMID: 38043349 DOI: 10.1016/j.watres.2023.120932] [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: 09/26/2023] [Revised: 11/16/2023] [Accepted: 11/27/2023] [Indexed: 12/05/2023]
Abstract
Sulfur-based autotrophic denitrification (SAD) coupled with anammox is a promising process for autotrophic nitrogen removal in view of the stable nitrite accumulation during SAD. In this study, a mixotrophic nitrogen removal system integrating SAD, anammox and heterotrophic denitrification was established in a single-stage reactor. The long-term nitrogen removal performance was investigated under the intervention of organic carbon sources in real municipal wastewater. With the shortening of hydraulic retention time, the nitrogen removal rate of the mixotrophic system dominated by the autotrophic subsystem reached 0.46 Kg N/m³/d at an organic loading rate of 0.57 Kg COD/m³/d, with COD and total nitrogen removal efficiencies of 82.5 % and 94 %, respectively, realizing an ideal combination of autotrophic and heterotrophic systems. The 15NO3--N isotope labeling experiments indicated that thiosulfate-driven autotrophic denitrification was the main pathway for nitrite supply accounting for 80.6 %, while anammox exhibited strong competitiveness for nitrite under the dual electron supply of sulfur and organic carbon sources and contributed to 65.1 % of nitrogen removal. Sludge granulation created differential functional distributions in different forms of sludge, with SAD showing faster reaction rate as well as higher nitrite accumulation rate in floc sludge, while anammox was more active in granular sludge. Real-time quantitative PCR, RT-PCR and high-throughput sequencing results revealed a dynamically changing community composition at the gene and transcription levels. The decrease in heterotrophic denitrification bacteria abundance indicated the effectiveness of the operational strategy for introduction of thiosulfate and maintaining the dominance of SAD in denitrification process in suppressing the excessive growth of heterotrophic bacteria in the mixotrophic system. The high transcriptional expression of sulfur-oxidizing bacteria (SOB) (Thiobacillus and Sulfurimonas) and anammox bacteria (Candaditus_Brocadia and Candidatus_Kuenenia) played a crucial role in the stable nitrogen removal.
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Affiliation(s)
- Qingteng Gong
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Wei Zeng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China.
| | - Biao Ma
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Xiaojing Hao
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Mengjia Zhan
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
| | - Yongzhen Peng
- National Engineering Laboratory for Advanced Municipal Wastewater Treatment and Reuse Technology, Beijing University of Technology, Beijing 100124, China
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Wu Y, Zhao Y, Jia X, Liu Y, Niu J. Phosphomolybdic acid enhancing hexavalent chromium bio-reduction in long-term operation: Optimal dosage and mechanism analysis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167328. [PMID: 37751836 DOI: 10.1016/j.scitotenv.2023.167328] [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: 07/26/2023] [Revised: 09/06/2023] [Accepted: 09/22/2023] [Indexed: 09/28/2023]
Abstract
The bio-reduction of Cr(VI) is regarded as a feasible and safe strategy to treat Cr pollution. The optimal concentration of phosphomolybdic acid (PMo12) for Cr(VI) reduction and the catalytic mechanism of electron behavior (electron production, electron transport and electron consumption) were revealed in denitrifying biofilm systems. The results showed that 0.1 mM PMo12 could achieve 92.5 % removal efficiency of 90 mg/L Cr(VI), which was 47.7 % higher than that of PMo12-free system, and improve the extracellular fixation capacity of Cr(III). The activity of peroxidase (POD) was significantly promoted by PMo12 to repair oxidative stress damage caused by Cr(VI) reduction. Additionally, analysis of electron behavior demonstrated that PMo12 could enhance key indicators of electron production, transport and consumption. This led to rapid activation of the electron pathway inhibited by Cr(VI), enabling simultaneous efficient nitrogen removal and Cr(VI) reduction in the biofilm system. This discovery will provide an efficient technique for Cr-containing wastewater treatment.
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Affiliation(s)
- Yichen Wu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China.
| | - Xvlong Jia
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yinuo Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jiaojiao Niu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
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8
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Yang S, Huang T, Zhang H, Tang Y, Guo H, Hu R, Cheng Y. Promoting aerobic denitrification in reservoir water with iron-activated carbon: Enhanced nitrogen and organics removal efficiency, and biological mechanisms. ENVIRONMENTAL RESEARCH 2024; 240:117452. [PMID: 37865328 DOI: 10.1016/j.envres.2023.117452] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/07/2023] [Revised: 09/28/2023] [Accepted: 10/17/2023] [Indexed: 10/23/2023]
Abstract
Carbon scarcity limits denitrification in micropolluted water, especially in drinking water reservoirs. Therefore, a Fe-activated carbon (AC) carrier was used in this study to enhance the nitrogen removal capacity of aboriginal denitrification in drinking water reservoirs under aerobic conditions. Following carrier addition, total nitrogen (TN) and permanganate index (CODMn) removal efficiencies reached 81.89% and 72.66%, respectively, and were enhanced by 40.45% and 39.65%. Nitrogen balance analysis indicated that 77.86% of the initial TN was converted into gaseous nitrogen. Biolog analysis suggested that the metabolic activity of denitrifying bacteria was substantially enhanced. 16S rRNA gene sequencing indicated that organic degradation bacteria, hydrogen-consuming, Fe-oxidizing, and Fe-reducing denitrifying bacteria (e.g., Arenimonas, Hydrogenophaga, Zoogloea, Methylibium, and Piscinibacter) evolved into the dominant species. Additionally, napA, nirS, nirK, and nosZ genes were enriched by 3.17, 6.68, 0.40, and 6.70 folds, respectively, which is conducive to complete denitrification. These results provide a novel pathway for the use of Fe-AC to promote aerobic denitrification in micropolluted drinking water reservoirs.
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Affiliation(s)
- Shangye Yang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Tinglin Huang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
| | - Haihan Zhang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Yun Tang
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Honghong Guo
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Ruzhu Hu
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Ya Cheng
- Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an, 710055, China; Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
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9
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Cao G, Gao J, Song J, Jia X, Liu Y, Niu J, Yuan X, Zhao Y. Performance and mechanism of chromium reduction in denitrification biofilm system with different carbon sources. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167191. [PMID: 37741376 DOI: 10.1016/j.scitotenv.2023.167191] [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: 07/14/2023] [Revised: 09/07/2023] [Accepted: 09/16/2023] [Indexed: 09/25/2023]
Abstract
In the process of biological reduction of Cr(VI), the type of carbon sources affects the rate and effect of Cr(VI) reduction, but its specific performance and influencing mechanism have not yet been explored. In this study, four denitrification biofilm reactors were operated under four common carbon sources (C6H12O6, CH3COONa, CH3OH, CH3COONa:C6H12O6 1:1) to reveal the impact of carbon sources on Cr(VI) reduction. Through preliminary experimental concentration research, 75 mg/L Cr(VI) was selected as the dosing concentration. In long-term operation, the composite carbon sources of CH3COONa and C6H12O6 demonstrated excellent stability and achieved an impressive Cr(VI) removal efficiency of 99.5 %. The following sequence was C6H12O6, CH3COONa, and CH3OH. Among them, CH3OH was less competitive and the system was severely unbalanced with lowest Cr(VI) reduction efficiency. The toxicity reactions, changes in EPS and its functional groups, and electron transfer revealed the reduction and fixation mechanism of chromium on denitrification biofilm. The changes in microbial communities indicated that microbial communities in composite carbon sources can quickly adapt to the high toxic environment. The proportion of Trichococcus reached 43.6 %, which played an important role in denitrification and Cr(VI) reduction. Meanwhile, the prediction of microbial COG function reflected its excellent metabolic ability and defense mechanism.
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Affiliation(s)
- Ge Cao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Junzhi Gao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jinxin Song
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Xvlong Jia
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yinuo Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jiaojiao Niu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Xin Yuan
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China.
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10
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Zhang H, Xu Z, Zhou P, Zhang Y, Wang Y. Simultaneous nitrate and chromium removal mechanism in a pyrite-involved mixotrophic biofilter. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2023; 30:123882-123892. [PMID: 37996574 DOI: 10.1007/s11356-023-31070-x] [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: 08/02/2023] [Accepted: 11/12/2023] [Indexed: 11/25/2023]
Abstract
Microbially mediated NO3--N and Cr(VI) reduction is being recognized as an eco-friendly and cost-effective remediation strategy. Iron sulfide mineral, as a natural inorganic electron donor, has a strong influence on NO3--N and Cr(VI) transformation, respectively. However, little is known about the simultaneous nitrate and chromium removal performance and underlying mechanism in an iron sulfide mineral-involved mixotrophic biofilter. This study demonstrated that the NO3--N and Cr(VI) removal efficiencies were stable at 62 ± 8% and 56 ± 10%, and most of them were eliminated in the 0-100-mm region of the biofilter. Cr(VI) was reduced to insoluble Cr(III) via microbial and chemical pathways, which was confirmed by the SEM-EDS morphology and the XPS spectra of biofilm and pyrite particles. SO42- was as a main byproduct of pyrite oxidation; however, the bacterial SO42- reduction synchronously occurred, evidenced by the variations of TOC and SO42- concentrations. These results suggested that there were complicated and intertwined biochemical relations between NO3--N/Cr(VI)/SO42-/DO (electron acceptors) and pyrite/organics (electron donors). Further investigation indicated that both the maximal biomass and greatest denitrifiers' relative abundances in microbial sample S1 well explained why the pollutants were removed in the 0-100-mm region. A variety of denitrifiers such as Pseudoxanthomona, Acidovorax, and Simplicispira were enriched, which probably were responsible for both NO3--N and Cr(VI) removal. Our findings advance the understanding of simultaneous nitrate and chromium removal in pyrite-involved mixotrophic systems and facilitate the new strategy development for nitrate and chromium remediation.
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Affiliation(s)
- Haigeng Zhang
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, 200092, China
| | - Zhongshuo Xu
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201600, China.
| | - Panpan Zhou
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201600, China
| | - Yulei Zhang
- Fishery Machinery and Instrument Research Institute, Chinese Academy of Fisheries Sciences, Shanghai, 200092, China
| | - Yuhui Wang
- College of Environmental Science and Engineering, Donghua University, Shanghai, 201600, China
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11
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Shao L, Wang D, Chen G, Zhao X, Fan L. Advance in the sulfur-based electron donor autotrophic denitrification for nitrate nitrogen removal from wastewater. World J Microbiol Biotechnol 2023; 40:7. [PMID: 37938419 DOI: 10.1007/s11274-023-03802-1] [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: 08/26/2023] [Accepted: 10/09/2023] [Indexed: 11/09/2023]
Abstract
In the field of wastewater treatment, nitrate nitrogen (NO3--N) is one of the significant contaminants of concern. Sulfur autotrophic denitrification technology, which uses a variety of sulfur-based electron donors to reduce NO3--N to nitrogen (N2) through sulfur autotrophic denitrification bacteria, has emerged as a novel nitrogen removal technology to replace heterotrophic denitrification in the field of wastewater treatment due to its low cost, environmental friendliness, and high nitrogen removal efficiency. This paper reviews the advance of reduced sulfur compounds (such as elemental sulfur, sulfide, and thiosulfate) and iron sulfides (such as ferrous sulfide, pyrrhotite, and pyrite) electron donors for treating NO3--N in wastewater by sulfur autotrophic denitrification technology, including the dominant bacteria types and the sulfur autotrophic denitrification process based on various electron donors are introduced in detail, and their operating costs, nitrogen removal performance and impacts on the ecological environment are analyzed and compared. Moreover, the engineering applications of sulfur-based electron donor autotrophic denitrification technology were comprehensively summarized. According to the literature review, the focus of future industry research were discussed from several aspects as well, which would provide ideas for the application and optimization of the sulfur autotrophic denitrification process for deep and efficient removal of NO3--N in wastewater.
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Affiliation(s)
- Lixin Shao
- School of Mechanical Engineering, Shenyang University of Technology, Shenyang, 110870, China
| | - Dexi Wang
- School of Mechanical Engineering, Shenyang University of Technology, Shenyang, 110870, China
| | - Gong Chen
- School of Chemical Equipment, Shenyang University of Technology, Liaoyang, 111000, China
| | - Xibo Zhao
- Weihai Baike Environmental Protection Engineering Co., Ltd., Weihai, 264200, China
| | - Lihua Fan
- School of Chemical Equipment, Shenyang University of Technology, Liaoyang, 111000, China.
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12
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Hu Y, Zhang J, Wang Y, Hu S. Distinct mechanisms shape prokaryotic community assembly across different land-use intensification. WATER RESEARCH 2023; 245:120601. [PMID: 37708774 DOI: 10.1016/j.watres.2023.120601] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Revised: 08/24/2023] [Accepted: 09/07/2023] [Indexed: 09/16/2023]
Abstract
Changes in land-use intensity can have a far-reaching impact on river water quality and prokaryotic community composition. While research has been conducted to investigate the assembly mechanism of prokaryotic communities, the contributions of neutral theory and niche theory to prokaryotic community assembly under different land-use intensities remain unknown. In this study, a total of 251 sampling sites were set up in the Yangtze River basin to explore the assembly mechanism under different land-use intensities. Briefly, a "source" landscape can generate pollution, whereas a "sink" landscape can prevent pollution. Firstly, our result showed that higher land-use intensity might disturb the balance between the "source" and "sink" landscape patterns, resulting in water quality deterioration. Then the prokaryotic community assembly was classified into five ecological processes, namely homogeneous selection, homogenizing dispersal, undominated processes, dispersal limitation, and variable selection. The higher land-use intensity was found to strengthen the homogeneous selection, leading to the homogenization of the community at the whole basin scale. Finally, our findings demonstrated that the Yangtze River Basin's prokaryotic community displayed a distance-decay pattern when land-use intensity was low, with a greater contribution from neutral theory to its assembly. On the other hand, with a higher land-use intensity, the degradation of the aquatic environment increased the impacts of environmental filtering on the prokaryotic community, and niche theory played a stronger role in its assembly. Our findings show how land-use intensity influence the formation of prokaryotic communities, which will be an invaluable guide for managing land use and understanding the prokaryotic community assembly mechanisms in the Yangtze River Basin.
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Affiliation(s)
- Yuxin Hu
- Yangtze River Basin Ecological Environment Monitoring and Scientific Research Center, Yangtze River Basin Ecological Environment Supervision and Administration Bureau, Ministry of Ecology and Environment, Wuhan 430010, Hubei, China.
| | - Jing Zhang
- Yangtze River Basin Ecological Environment Monitoring and Scientific Research Center, Yangtze River Basin Ecological Environment Supervision and Administration Bureau, Ministry of Ecology and Environment, Wuhan 430010, Hubei, China
| | - Yingcai Wang
- Yangtze River Basin Ecological Environment Monitoring and Scientific Research Center, Yangtze River Basin Ecological Environment Supervision and Administration Bureau, Ministry of Ecology and Environment, Wuhan 430010, Hubei, China.
| | - Sheng Hu
- Yangtze River Basin Ecological Environment Monitoring and Scientific Research Center, Yangtze River Basin Ecological Environment Supervision and Administration Bureau, Ministry of Ecology and Environment, Wuhan 430010, Hubei, China.
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13
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Wang Q, Zhao Y, Chen Z, Zhang C, Jia X, Zhao M, Tong Y, Liu Y. Nitrate Bioreduction under Cr(VI) Stress: Crossroads of Denitrification and Dissimilatory Nitrate Reduction to Ammonium. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2023. [PMID: 37449976 DOI: 10.1021/acs.est.2c09624] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/18/2023]
Abstract
This study explored the response of NO3--N bioreduction to Cr(VI) stress, including reduction efficiency and the pathways involved (denitrification and dissimilatory nitrate reduction to ammonium (DNRA)). Different response patterns of NO3--N conversion were proposed under Cr(VI) suppress (0, 0.5, 5, 15, 30, 50, and 80 mg/L) by evaluating Cr(VI) dose dependence, toxicity accumulation, bioelectron behavior, and microbial community structure. Cr(VI) concentrations of >30 mg/L rapidly inhibited NO3--N removal and immediately induced DNRA. However, denitrification completely dominated the NO3--N reduction pathway at Cr(VI) concentrations of <15 mg/L. Therefore, 30 and 80 mg/L Cr(VI) (R4 and R6) were selected to explore the selection of the different NO3--N removal pathways. The pathway of NO3--N reduction at 30 mg/L Cr(VI) exhibited continuous adaptation, wherein the coexistence of denitrification (51.7%) and DNRA (13.6%) was achieved by regulating the distribution of denitrifiers (37.6%) and DNRA bacteria (32.8%). Comparatively, DNRA gradually replaced denitrification at 80 mg/L Cr(VI). The intracellular Cr(III) accumulation in R6 was 6.60-fold greater than in R4, causing more severe oxidant injury and cell death. The activated NO3--N reduction pathway depended on the value of nitrite reductase activity/nitrate reductase activity, with 0.84-1.08 associated with DNRA activation and 1.48-1.57 with DNRA predominance. Although Cr(VI) increased microbial community richness and improved community structure stability, the inhibition or death of nitrogen-reducing microorganisms caused by Cr(VI) decreased NO3--N reduction efficiency.
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Affiliation(s)
- Qian Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Zhihui Chen
- China Water Resources Bei Fang Investigation, Design & Research CO.LTD, Tianjin 300222, China
| | - Chenggong Zhang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Xulong Jia
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Minghao Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yindong Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yiwen Liu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
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14
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Pan Y, Fu YY, Zhou K, Tian T, Li YS, Yu HQ. Microbial mixotrophic denitrification using iron(II) as an assisted electron donor. WATER RESEARCH X 2023; 19:100176. [PMID: 37020531 PMCID: PMC10068250 DOI: 10.1016/j.wroa.2023.100176] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/08/2023] [Revised: 03/15/2023] [Accepted: 03/16/2023] [Indexed: 06/19/2023]
Abstract
Mixotrophic denitrification processes have a great potential in nitrogen removal in biological wastewater treatment processes. However, so far, few studies have focused on the mixotrophic denitrification system using Fe(II) as an exclusively assisted electron donors and the underlying mechanisms in such a process remain unclear. Furthermore, the mechanisms by which microorganisms cover carbon, nitrogen, phosphorus and iron in an iron-assisted mixotrophic system remain unrevealed. In this work, we explore the feasibility of using Fe(II) as an assisted electron donor for enhancing simultaneous nitrogen and phosphorus removal via long-term reactor operation and batch tests. The results show that Fe(II) could provide electrons for efficient nitrate reduction and that biological reactions played a predominant role in these systems. In these systems Thermomonas, a strain of nitrate-reduction Fe(II)-oxidation bacterium, was enriched and accounted for a maximum abundance of 60.2%. These findings indicate a great potential of the Fe(II)-assisted mixotrophic denitrification system for practical use as an efficient simultaneous nitrogen and phosphorus removal process.
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Affiliation(s)
- Yuan Pan
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
- Anhui Province Key Laboratory of Industrial Wastewater and Environmental Treatment, Hefei 230026, China
| | - Ying-Ying Fu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Ke Zhou
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Tian Tian
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
- Key Laboratory of Industrial Ecology and Environmental Engineering (Ministry of Education, China), School of Environmental Science and Technology, Dalian University of Technology, Dalian 116024, China
| | - Yu-Sheng Li
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
| | - Han-Qing Yu
- CAS Key Laboratory of Urban Pollutant Conversion, Department of Environmental Science and Engineering, University of Science and Technology of China, Hefei 230026, China
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15
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Zhang J, Fan C, Zhao M, Wang Z, Jiang S, Jin Z, Bei K, Zheng X, Wu S, Lin P, Miu H. A comprehensive review on mixotrophic denitrification processes for biological nitrogen removal. CHEMOSPHERE 2023; 313:137474. [PMID: 36493890 DOI: 10.1016/j.chemosphere.2022.137474] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/23/2022] [Revised: 11/18/2022] [Accepted: 12/03/2022] [Indexed: 06/17/2023]
Abstract
Biological denitrification is the most widely used method for nitrogen removal in water treatment. Compared with heterotrophic and autotrophic denitrification, mixotrophic denitrification is later studied and used. Because mixotrophic denitrification can overcome some shortcomings of heterotrophic and autotrophic denitrification, such as a high carbon source demand for heterotrophic denitrification and a long start-up time for autotrophic denitrification. It has attracted extensive attention of researchers and is increasingly used in biological nitrogen removal processes. However, so far, a comprehensive review is lacking. This paper aims to review the current research status of mixotrophic denitrification and provide guidance for future research in this field. It is shown that mixotrophic denitrification processes can be divided into three main kinds based on different kinds of electron donors, mainly including sulfur-, hydrogen-, and iron-based reducing substances. Among them, sulfur-based mixotrophic denitrification is the most widely studied. The most concerned influencing factors of mixotrophic denitrification processes are hydraulic retention times (HRT) and ratio of chemical oxygen demand (COD) to total inorganic nitrogen (C/N). The dominant functional bacteria of sulfur-based mixotrophic denitrification system are Thiobacillus, Azoarcus, Pseudomonas, and Thauera. At present, mixotrophic denitrification processes are mainly applied for nitrogen removal in drinking water, groundwater, and wastewater treatment. Finally, challenges and future research directions are discussed.
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Affiliation(s)
- Jintao Zhang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Chunzhen Fan
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Min Zhao
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Zhiquan Wang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Shunfeng Jiang
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Zhan Jin
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Ke Bei
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China
| | - Xiangyong Zheng
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China.
| | - Suqing Wu
- College of Life and Environmental Science, Wenzhou University, Wenzhou, Zhejiang, 325035, PR China; National and Local Joint Engineering Research Center of Ecological Treatment Technology for Urban Water Pollution, Wenzhou, Zhejiang, 325035, PR China; Zhejiang Provincial Key Lab for Water Environment and Marine Biological Resources Protection, Wenzhou, Zhejiang, 325035, PR China.
| | - Ping Lin
- Wenzhou Drainage Co., Ltd, Wenzhou, Zhejiang, 325000, PR China
| | - Huanyi Miu
- Wenzhou Ecological Park Development and Construction Investment Group Co., Ltd, Wenzhou, Zhejiang, 325000, PR China
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16
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Yılmaz T, Sahinkaya E. Performance of sulfur-based autotrophic denitrification process for nitrate removal from permeate of an MBR treating textile wastewater and concentrate of a real scale reverse osmosis process. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2023; 326:116827. [PMID: 36442334 DOI: 10.1016/j.jenvman.2022.116827] [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: 08/21/2022] [Revised: 11/10/2022] [Accepted: 11/16/2022] [Indexed: 06/16/2023]
Abstract
Textile is one of the industrial sectors generating the highest amount of wastewater with various polluting substances. Lately, water reuse in textile industries, especially, with the reverse osmosis (RO) process following membrane bioreactor (MBR) treatment has been applied more commonly. In this study, an autotrophic sulfur-based denitrifying column performance was evaluated, for the first time, for nitrate reduction from permeate of a lab-scale MBR receiving real textile wastewater and from the concentrate stream of a real scale-RO plant used for recovering water from textile wastewater. Nitrate concentration in the MBR effluent and RO concentrate averaged 35 ± 3 and 12 ± 2 mg-N/L, respectively. With the sulfur-based column bioreactor, quite high (≥90%) denitrification performances were attained both for MBR effluent and RO concentrate up to nitrate loadings of 0.432 and 0.12 g-N/(L.d), respectively. COD present in wastewater was not utilized in the column bioreactor, which illustrates no or minimal contribution of heterotrophic denitrification. Alkalinity concentration in the wastewater was enough to buffer the acid formation during autotrophic denitrification. Sulfate was generated accompanied by nitrate reduction and sulfide was formed at low nitrate loadings. In the batch tests, the denitrification rates for the MBR effluent and RO concentrate were 0.31 and 0.28 g-N/(g-VSS.d), respectively, which were relatively higher than the ones observed for the synthetic nitrate-contaminated groundwater. Autotrophic sulfur-based denitrification is a promising and robust process alternative even for textile RO concentrate with high concentrations of salinity, non-biodegradable COD, and color.
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Affiliation(s)
- Tülay Yılmaz
- Environmental Engineering Department, Istanbul Technical University, Maslak, 34469, Istanbul, Turkey; Science and Advanced Technologies Research Center (BILTAM), Istanbul Medeniyet University, Istanbul, 34700, Turkey
| | - Erkan Sahinkaya
- Science and Advanced Technologies Research Center (BILTAM), Istanbul Medeniyet University, Istanbul, 34700, Turkey; Department of Bioengineering, Istanbul Medeniyet University, Istanbul, 34700, Turkey.
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17
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Ashun E, Kang W, Thapa BS, Gurung A, Rahimnejad M, Jang M, Jeon BH, Kim JR, Oh SE. A novel gas production bioassay of thiosulfate utilizing denitrifying bacteria (TUDB) for the toxicity assessment of heavy metals contaminated water. CHEMOSPHERE 2022; 303:134902. [PMID: 35561773 DOI: 10.1016/j.chemosphere.2022.134902] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 04/25/2022] [Accepted: 05/06/2022] [Indexed: 06/15/2023]
Abstract
This study reports for the first-time the possibility of deploying gas production by thiosulfate utilizing denitrifying bacteria (TUDB) as a proxy to evaluate water toxicity. The test relies on gas production by TUDB due to inhibited metabolic activity in the presence of toxicants. Gas production was measured using a bubble-type respirometer. Optimization studies indicated that 300 mg NO3--N/L, 0.5 mL acclimated culture, and 2100 mg S2O32-/L were the ideal conditions facilitating the necessary volume of gas production for sensitive data generation. Determined EC50 values of the selected heavy metals were: Cr6+, 0.51 mg/L; Ag+, 2.90 mg/L; Cu2+, 2.90 mg/L; Ni2+, 3.60 mg/L; As3+, 4.10 mg/L; Cd2+, 5.56 mg/L; Hg2+, 8.06 mg/L; and Pb2+, 19.3 mg/L. The advantages of this method include operational simplicity through the elimination of cumbersome preprocessing procedures which are used to eliminate interferences caused by turbidity when the toxicity of turbid samples is determined via spectrophotometry.
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Affiliation(s)
- Ebenezer Ashun
- Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si, 200-701, Republic of Korea
| | - Woochang Kang
- Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si, 200-701, Republic of Korea
| | - Bhim Sen Thapa
- Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si, 200-701, Republic of Korea
| | - Anup Gurung
- Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si, 200-701, Republic of Korea
| | - Mostafa Rahimnejad
- Biofuel and Renewable Energy Research Center, Chemical Engineering Department, Babol Noshirvani University of Technology, Babol, Islamic Republic of Iran
| | - Min Jang
- Department of Environmental Engineering, Kwangwoon University, 20 Kwangwoon-Ro, Nowon-Gu, Seoul 01897, Republic of Korea
| | - Byong-Hun Jeon
- Department of Earth Resources and Environmental Engineering, Hanyang University, Seoul 04763, Republic of Korea
| | - Jung Rae Kim
- School of Chemical Engineering, Pusan National University, 63 Busandeahak-ro, Geumjeong-Gu, Busan 46241, Republic of Korea
| | - Sang-Eun Oh
- Department of Biological Environment, Kangwon National University, 192-1 Hyoja-dong, Gangwon-do, Chuncheon-si, 200-701, Republic of Korea.
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18
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Guo Y, Guo L, Jin C, Zhao Y, Gao M, Ji J, She Z, Giesy JP. Comparison of primary and secondary sludge carbon sources derived from hydrolysis or acidogenesis for nitrate reduction and denitrification kinetics: Organics utilization and microbial community shift. ENVIRONMENTAL RESEARCH 2022; 212:113403. [PMID: 35525291 DOI: 10.1016/j.envres.2022.113403] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Revised: 04/23/2022] [Accepted: 04/28/2022] [Indexed: 06/14/2023]
Abstract
Seeking available and economical carbon sources for denitrification process is an intractable issue for wastewater treatment. However, no study compared different types of waste sludge as carbon source from denitrification mechanism, organics utilization and microbial community aspects. In this study, primary and secondary sludge were pretreated by thermophilic bacteria (TB), and its hydrolysis or acidogenic liquid were prepared as carbon sources for denitrification. At C/N of 8-3, the variations of NO3--N and NO2--N were profiled in typical cycles and denitrification kinetics was analyzed. Primary sludge achieved a competitive NOX-N removal efficiency with less dosage than secondary sludge. Fourier transform infrared (FTIR) spectroscopy was introduced to analyze organic composition from functional-group perspective and the utilization of organic matters in different sludge carbon sources was investigated. To further analyze the microbial community shift in different denitrification systems, high-throughput sequencing technology was applied. Results showed that denitrifier Thauera, belonging to Proteobacteria, was predominant, and primary sludge acidogenic liquid enriched Thauera most intensively with relative abundance of 47.3%.
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Affiliation(s)
- Yiding Guo
- College of Environmental Science and Engineering, Tongji University, Shanghai, 200092, China; College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Liang Guo
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China; Key Laboratory of Marine Environmental and Ecology, Ministry of Educatin, Ocean University of China, Qingdao, 266100, China.
| | - Chunji Jin
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Yangguo Zhao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Mengchun Gao
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - Junyuan Ji
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China.
| | - Zonglian She
- College of Environmental Science and Engineering, Ocean University of China, Qingdao, 266100, China
| | - John P Giesy
- Department of Veterinary Biomedical Sciences and Toxicology Centre, University of Saskatchewan, Saskatoon, Saskatchewan, Canada; Department of Environmental Science, Baylor University, Waco, TX, USA
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19
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Zhao Y, Wang Q, Yang Z, Jia X, Cabrera J, Ji M. Bio-capture of Cr(VI) in a denitrification system: Electron competition, long-term performance, and microbial community evolution. JOURNAL OF HAZARDOUS MATERIALS 2022; 432:128697. [PMID: 35334263 DOI: 10.1016/j.jhazmat.2022.128697] [Citation(s) in RCA: 16] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Revised: 03/10/2022] [Accepted: 03/11/2022] [Indexed: 06/14/2023]
Abstract
Chromium is widely applied in industries as an important metal resource, but the discharge of Cr(VI) containing wastewater leads to the loss of chromium resources. This study proposed a bio-capture process of chromium in a denitrification system. The bio-capture potentiality was explored by investigating the electron competition between Cr(VI) and nitrogen compounds reduction, the long-term bio-capture performance, and the microbial community evolution. In the competition utilization of electron donors, both NO3--N and NO2--N took precedence over Cr(VI), and NO2--N reduction was proved to be the rate-limiting step. Under the optimum conditions of 20 mg/L NO3--N and 6 h HRT, 99.95% of 30 mg/L Cr(VI) could be reduced, and 220980 μg Cr/g MLSS was captured by the biofilm, which was fixed in intercellular as Cr(III). Microbiological analysis confirmed that the bio-reduction of Cr(VI) and NO3--N was mediated by synergistic interactions of a series of dominant bacteria, including genera Acidovorax, Thermomonas, and Microbacterium, which contained both the denitrification genes (narG, narZ, nxrA, and nirK) and chromate reduction genes (chrA and chrR). This study proved the feasibility of chromium bio-capture in denitrification systems and provided a new perspective for the Cr(VI) pollution treatment.
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Affiliation(s)
- Yingxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China.
| | - Qian Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Zhifan Yang
- Tianjin Municipal Engineering Design & Research Institute Co. Ltd., Tianjin 300380, China
| | - Xulong Jia
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Jonnathan Cabrera
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Min Ji
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
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20
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Zhang H, Ma B, Huang T, Yang W, Liu X, Niu L. Nitrogen removal from low carbon/nitrogen polluted water is enhanced by a novel synthetic micro-ecosystem under aerobic conditions: Novel insight into abundance of denitrification genes and community interactions. BIORESOURCE TECHNOLOGY 2022; 351:127013. [PMID: 35306134 DOI: 10.1016/j.biortech.2022.127013] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/27/2022] [Revised: 03/11/2022] [Accepted: 03/12/2022] [Indexed: 06/14/2023]
Abstract
The main limiting factor in treatment of wastewater with a low carbon/nitrogen ratio is insufficient electron donors for aerobic denitrification. A novel synthetic micro-ecosystem (SM) with functional materials as the core structure was prepared to enhance nitrate removal during wastewater treatment. Nitrate removal in the reactors with SM increased by more than 40 % and reached 97.43 % under aerobic conditions. The abundance of denitrification functional genes in activated sludge increased by 2.7 folds after adding SM. Network analysis showed that the denitrifying bacterial community in the reactors with SM displayed a more abundant symbiotic structure. In the reactors with SM, bacteria with both denitrification and inorganic electron transfer capabilities (such as Paracoccus sp., Thaurea sp., and Achromobacter sp.) occupied dominant niche. A species abundance distribution model indicated more intense competition for the dominant niche for the denitrification community in the reactor with SM. Thus, SM promotes denitrification in polluted water bodies under aerobic conditions.
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Affiliation(s)
- Haihan Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China.
| | - Ben Ma
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Tinglin Huang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Wanqiu Yang
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Xiang Liu
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
| | - Limin Niu
- Shaanxi Key Laboratory of Environmental Engineering, Key Laboratory of Northwest Water Resource, Environment and Ecology, MOE, Xi'an University of Architecture and Technology, Xi'an 710055, China; School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an 710055, China
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21
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He Y, Guo J, Song Y, Chen Z, Lu C, Han Y, Li H, Hou Y. Te(IV) bioreduction in the sulfur autotrophic reactor: Performance, kinetics and synergistic mechanism. WATER RESEARCH 2022; 214:118216. [PMID: 35228038 DOI: 10.1016/j.watres.2022.118216] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/20/2021] [Revised: 02/12/2022] [Accepted: 02/18/2022] [Indexed: 06/14/2023]
Abstract
A laboratory-scale sulfur autotrophic reactor (SAR) was first constructed for treating tellurite [Te(IV)] wastewater. The SAR had excellent Te(IV) bioreduction efficiency (90-96%) at 5-30 mg/L and conformed to the First-order kinetic model. The Te(IV) bioreduction was elaborated deeply from extracellular polymeric substances (EPS) functions, microbial metabolic activity, key enzyme activity, microbial community succession and quorum sensing. Te(IV) stimulated the increase of redox substances in EPS and the improved cell membrane permeability led to the increase of electron transport system activity. Catalase and reduced nicotinamide adenine dinucleotide (NADH) alleviated the oxidative stress caused by Te(IV) toxicity to maintain metabolic activity. The increase of sulfur dioxygenase activity (SDO) suggested that more ATP produced by sulfur oxidation might provide energy for various physiological activities. Meanwhile, nitrate reductase (NAR), nitrite reductase (NIR) and sulfide: quinone oxidoreductase (SQR) played an active role in sulfur oxidation and Te(IV) bioreduction. Combined with the above results and dynamic succession of three functional microbial communities, a synergistic mechanism was proposed to explain the excellent performance of SAR. This work provided a promising strategy for Te(IV) wastewater treatment process and Te(IV) bioreduction mechanism.
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Affiliation(s)
- Yue He
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
| | - Jianbo Guo
- School of Civil Engineering and Architecture, Taizhou University, Taizhou 318000, Zhejiang, China; School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China.
| | - Yuanyuan Song
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
| | - Zhi Chen
- Department of Building, Civil, and Environmental Engineering, Concordia University, 1455 de Maisonneuve Blvd. W. Montreal, Quebec, Canada
| | - Caicai Lu
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
| | - Yi Han
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
| | - Haibo Li
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
| | - Yanan Hou
- School of Environmental and Municipal Engineering, Tianjin Key Laboratory of Aquatic Science and Technology, Tianjin Chengjian University, Jinjing Road 26, Tianjin 300384, China
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22
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Pang Y, Wang J. Various electron donors for biological nitrate removal: A review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 794:148699. [PMID: 34214813 DOI: 10.1016/j.scitotenv.2021.148699] [Citation(s) in RCA: 127] [Impact Index Per Article: 42.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/22/2021] [Revised: 06/22/2021] [Accepted: 06/22/2021] [Indexed: 06/13/2023]
Abstract
Nitrate (NO3-) pollution in water and wastewater has become a serious global issue. Biological denitrification, which reduces NO3- to N2 (nitrogen gas) by denitrifying microorganisms, is an efficient and economical process for the removal of NO3- from water and wastewater. During the denitrification process, electron donor is required to provide electrons for reduction of NO3-. A variety of electron donors, including organic and inorganic compounds, can be used for denitrification. This paper reviews the state of the art of various electron donors used for biological denitrification. Depending on the types of electron donors, denitrification can be classified into heterotrophic and autotrophic denitrification. Heterotrophic denitrification utilizes organic compounds as electron donors, including low-molecular-weight organics (e.g. acetate, methanol, glucose, benzene, methane, etc.) and high-molecular-weight organics (e.g. cellulose, polylactic acid, polycaprolactone, etc.); while autotrophic denitrification utilizes inorganic compounds as electron donors, including hydrogen (H2), reduced sulfur compounds (e.g. sulfide, element sulfur and thiosulfate), ferrous iron (Fe2+), iron sulfides (e.g. FeS, Fe1-xS and FeS2), arsenite (As(Ш)) and manganese (Mn(II)). The biological denitrification processes and the representative denitrifying microorganisms are summarized based on different electron donors, and their denitrification performance, operating costs and environmental impacts are compared and discussed. The pilot- or full-scale applications were summarized. The concluding remarks and future prospects were provided. The biodegradable polymers mediated heterotrophic denitrification, as well as H2 and sulfur mediated autotrophic denitrification are promising denitrification processes for NO3- removal from various types of water and wastewater.
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Affiliation(s)
- Yunmeng Pang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China
| | - Jianlong Wang
- Laboratory of Environmental Technology, INET, Tsinghua University, Beijing 100084, PR China; Beijing Key Laboratory of Radioactive Waste Treatment, INET, Tsinghua University, Beijing 100084, PR China.
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23
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Asik G, Yilmaz T, Di Capua F, Ucar D, Esposito G, Sahinkaya E. Sequential sulfur-based denitrification/denitritation and nanofiltration processes for drinking water treatment. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2021; 295:113083. [PMID: 34171780 DOI: 10.1016/j.jenvman.2021.113083] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2021] [Revised: 06/07/2021] [Accepted: 06/12/2021] [Indexed: 06/13/2023]
Abstract
Efficient and cost-effective solutions for nitrogen removal are necessary to ensure the availability of safe drinking water. This study proposes a combined treatment for nitrogen-contaminated groundwater by sequential autotrophic nitrogen removal in a sulfur-packed bed reactor (SPBR) and excess sulfate rejection via nanofiltration (NF). Autotrophic nitrogen removal in the SPBR was investigated under both denitrification and denitritation conditions under different NO3- and NO2- loading rates (LRs) and feeding strategies (NO3- only, NO2- only, or both NO3- and NO2- in the feed). Batch activity tests were carried out during SPBR operation to evaluate the effect of different feeding conditions on nitrogen removal activity by the SPBR biofilm. Bacteria responsible for nitrogen removal in the bioreactor were identified via Illumina sequencing. Dead-end filtration tests were performed with NF membranes to investigate the elimination of excess sulfate from the SPBR effluent. This study demonstrates that the combined process results in effective groundwater treatment and evidences that an adequately high nitrogen LR should be maintained to avoid the generation of excess sulfide.
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Affiliation(s)
- Gulfem Asik
- Bioengineering Department, Istanbul Medeniyet University, Uskudar, Istanbul, Turkey
| | - Tulay Yilmaz
- Environmental Engineering Department, Faculty of Civil Engineering, Istanbul Technical University, 34469, Maslak, Istanbul, Turkey
| | - Francesco Di Capua
- Department of Civil, Environmental, Land, Building Engineering and Chemistry, Polytechnic University of Bari, Via E. Orabona 4, 70125, Bari, Italy; Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125, Naples, Italy
| | - Deniz Ucar
- Department of Environmental Engineering, Bursa Technical University, 16310, Bursa, Turkey
| | - Giovanni Esposito
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, Via Claudio 21, 80125, Naples, Italy
| | - Erkan Sahinkaya
- Bioengineering Department, Istanbul Medeniyet University, Uskudar, Istanbul, Turkey.
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24
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Hu Y, Liu T, Chen N, Feng C. Iron oxide minerals promote simultaneous bio-reduction of Cr(VI) and nitrate: Implications for understanding natural attenuation. THE SCIENCE OF THE TOTAL ENVIRONMENT 2021; 786:147396. [PMID: 33964780 DOI: 10.1016/j.scitotenv.2021.147396] [Citation(s) in RCA: 24] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 04/09/2021] [Accepted: 04/23/2021] [Indexed: 06/12/2023]
Abstract
Nitrate and Cr(VI) coexist in aquifers, posing a potential threat to ecological environment and public health. Iron oxide minerals (hematite and magnetite) exist ubiquitously in groundwater, which are hot spots for biogeochemical transformation. However, there is still a knowledge gap anout the effect of iron oxide minerals on bioreduction of nitrate and Cr(VI). Here we observed that iron oxide minerals can significantly improve the ability of microorganisms to simultaneously reduce nitrate and Cr(VI), the reduction rates of nitrate and Cr(VI) increased by 7.3 and 8.5 times, respectively. The addition of minerals reinforced biofilm formation and shaped microbial communities with a new dominant strain of Azoarcus. The expression levels of functional genes were also upregulated, including napA, narG, nfsA, yieF, POD, and CAT. Furthermore, nitrate and chromate reductases' activities increased by 11 and 5 folds, respectively. These results demonstrated that iron oxide minerals participated in the bio-transformation of nitrate and Cr(VI) co-contamination, alleviating oxidative stress, shaping the microbial community, and ultimately accelerating bio-transformation. These findings offer a window into the biological transformation of co-contamination in the presence of iron oxide minerals, and insights to reveal strategies for microbial detoxification and to develop promising approaches for dealing with complex pollution conditions.
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Affiliation(s)
- Yutian Hu
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Tong Liu
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
| | - Nan Chen
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China.
| | - Chuanping Feng
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution, China University of Geosciences (Beijing), Beijing 100083, PR China
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25
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Mixotrophic bacteria for environmental detoxification of contaminated waste and wastewater. Appl Microbiol Biotechnol 2021; 105:6627-6648. [PMID: 34468802 DOI: 10.1007/s00253-021-11514-5] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2021] [Revised: 08/06/2021] [Accepted: 08/10/2021] [Indexed: 12/31/2022]
Abstract
Mixotrophic bacteria provide a desirable alternative to the use of classical heterotrophic or chemolithoautotrophic bacteria in environmental technology, particularly under limiting nutrients conditions. Their bi-modal ability of adapting to inorganic or organic carbon feed and sulfur, nitrogen, or even heavy metal stress conditions are attractive features to achieve efficient bacterial activity and favorable operation conditions for the environmental detoxification or remediation of contaminated waste and wastewater. This review provides an overview on the state of the art and summarizes the metabolic traits of the most promising and emerging non-model mixotrophic bacteria for the environmental detoxification of contaminated wastewater and waste containing excess amounts of limiting nutrients. Although mixotrophic bacteria usually function with low organic carbon sources, the unusual capabilities of mixotrophic electroactive exoelectrogens and electrotrophs in bioelectrochemical systems and in microbial electrosynthesis for accelerating simultaneous metabolism of inorganic or organic C and N, S or heavy metals are reviewed. The identification of the mixotrophic properties of electroactive bacteria and their capability to drive mono- or bidirectional electron transfer processes are highly exciting and promising aspects. These aspects provide an appealing potential for unearthing new mixotrophic exoelectrogens and electrotrophs, and thus inspire the next generation of microbial electrochemical technology and mixotrophic bacterial metabolic engineering. KEY POINTS: • Mixotrophic bacteria efficiently and simultaneously remove C and N, S or heavy metals. • Exoelectrogens and electrotrophs accelerate metabolism of C and N, S or heavy metals. • New mixotrophic exoelectrogens and electrotrophs should be discovered and exploited.
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26
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Zhang S, Zhang L, Chen P, Rong H, Li S. Deciphering the microbial patterns of anammox process under hexavalent chromium stress: Abundant and rare subcommunity respond differently. JOURNAL OF HAZARDOUS MATERIALS 2021; 416:125850. [PMID: 34492801 DOI: 10.1016/j.jhazmat.2021.125850] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/26/2021] [Revised: 03/14/2021] [Accepted: 04/06/2021] [Indexed: 06/13/2023]
Abstract
This study aims to unravel the microbial responses to Cr(VI) stress in anaerobic ammonium oxidation (anammox) reactor. The result showed that anammox process could tolerate 2 mg/L Cr(VI) after acclimation, while 5 mg/L Cr(VI) stress resulted in significant inhibition on anammox bacterial activity. Ca. Jettenia was the predominant anammox genus, whose abundance showed a decreasing tendency with increasing Cr(VI) dosage. Cr(VI) addition resulted in significant and irreversible changes in microbial community structure, and increased the relative influence of stochastic processes on community assembly. Furthermore, rare subcommunity contributed greatly to biodiversity of whole community (90.35%), while abundant subcommunity were more similar to the whole community. Importantly, Cr(VI) exposure caused greater variations in rare subcommunity compared with abundant one, indicating that rare taxa were more sensitive to Cr(VI) stress. This was further confirmed by ABT model, which showed higher relative influence of Cr(VI) on rare subcommunity. In addition, results suggested that rare taxa play essential roles in whole community stability, because of their great contribution to species richness and community variations, and keystone roles in ecosystem network. Moreover, network analysis showed that conditionally rare taxa frequently and positively interacted with abundant taxa, which may contribute to the community resilience to Cr(VI) stress.
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Affiliation(s)
- Shaoqing Zhang
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China
| | - Liqiu Zhang
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, PR China
| | - Peng Chen
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China
| | - Hongwei Rong
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China; Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, PR China.
| | - Shugeng Li
- Key Laboratory for Water Quality and Conservation of the Pearl River Delta, Ministry of Education, Guangzhou University, Guangzhou 510006, PR China; School of Environmental Science and Engineering, Guangzhou University, Guangzhou 510006, PR China.
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27
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Li D, Li G, Zhang D. Field-scale studies on the change of soil microbial community structure and functions after stabilization at a chromium-contaminated site. JOURNAL OF HAZARDOUS MATERIALS 2021; 415:125727. [PMID: 34088197 DOI: 10.1016/j.jhazmat.2021.125727] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/13/2021] [Revised: 03/14/2021] [Accepted: 03/19/2021] [Indexed: 05/20/2023]
Abstract
Various remediation strategies have been developed to eliminate soil chromium (Cr) contamination which challenges the ecosystem and human health, and chemical stabilization is the most popular one. Limited work focuses on the change of soil microbial community and functions after chemical stabilization. The present study examined the diversity and structure of bacterial, fungal and archaeal communities in 20 soils from a Cr-contaminated site in China after chemical stabilization and ageing. Cr contamination significantly reduced microbial diversity and shaped microbial community structure. After chemical stabilization, bacterial and fungal communities had higher richness and evenness, whereas archaea behaved oppositely. Microbial community structure after stabilization were more similar to uncontaminated soils. Among all environmental variables, pH and Al explained 25.2% and 9.4% of the total variance of bacterial diversity, whereas the major variable affecting fungal community was pH (29.3%). Cr, organic matters, extractable-Al and moisture explained 25.8%, 22.4%, 9.9% and 9.9% of the total variance in archaeal community, respectively. This work for the first time unraveled the change of the whole soil microbial community structures and functions at Cr-contaminated sites after chemical stabilization on field scale and proved chemical stabilization as an effective approach to detoxicate Cr(VI) and recover microbial communities in soils.
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Affiliation(s)
- Danni Li
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China
| | - Guanghe Li
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China
| | - Dayi Zhang
- School of Environment, Tsinghua University, Beijing 100084, China; National Engineering Laboratory for Site Remediation Technologies, Beijing 100015, China.
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28
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Lyu Y, Yang T, Liu H, Qi Z, Li P, Shi Z, Xiang Z, Gong D, Li N, Zhang Y. Enrichment and characterization of an effective hexavalent chromium-reducing microbial community YEM001. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2021; 28:19866-19877. [PMID: 33410044 DOI: 10.1007/s11356-020-11863-0] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2020] [Accepted: 11/27/2020] [Indexed: 06/12/2023]
Abstract
Chromium (Cr) is one of the most widely used heavy metals in industrial processes, resulting in water and soil pollution that seriously threaten environmental safety. In this paper, we have directionally enriched a Cr(VI)-reducing bacterial community YEM001 from no-Cr(VI) polluted pond sedimental sludge by selectively growing it in Cr(VI)-containing media. This community could effectively reduce Cr(VI) in laboratory rich media containing different concentrations of Cr(VI), such as 61% reduction at 435 mg/L Cr(VI), 85% reduction at 355 mg/L Cr(VI), and complete reduction at 269 mg/L Cr(VI) in 93.5 h. It was also able to completely reduce 100 mg/L and 300 mg/L Cr(VI) in landfill leachate and natural sludge in 48 h, respectively. Optimal pH for Cr(VI) reduction of the YEM001 is between 7 and 8 and the best efficiency for Cr(VI) reduction occurs at 30 °C. Metagenomic data demonstrated that the YEM001 community was composed of multiple bacteria, including well-known Cr(VI)-reducing bacteria and non-Cr(VI)-reducing bacteria. Delftia, Comamonas, Alicycliphilus, Acidovorax, Bacillus, and Clostridioides account for 83% of total community abundance. The stability of the composition of the YEM001 community and its Cr(VI)-reducing activity allows for its application in bioremediation of environmental Cr(VI) pollution.
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Affiliation(s)
- Yucai Lyu
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China.
- Hubei Engineering Technology Research Center for Farmland Environmental Monitoring, China Three Gorges University, Yichang, 443002, China.
- Key Laboratory of Functional Yeast, China National Light Industry, China Three Gorges University, Yichang, 443002, China.
| | - Tao Yang
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China
| | - Herong Liu
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China
| | - Zheng Qi
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China
| | - Ping Li
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China
| | - Ziyao Shi
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang, 443002, China
| | - Zhen Xiang
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang, 443002, China
| | - Dachun Gong
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China
- Hubei Engineering Technology Research Center for Farmland Environmental Monitoring, China Three Gorges University, Yichang, 443002, China
- Key Laboratory of Functional Yeast, China National Light Industry, China Three Gorges University, Yichang, 443002, China
| | - Ning Li
- College of Hydraulic and Environmental Engineering, China Three Gorges University, Yichang, 443002, China
| | - Yaoping Zhang
- Hubei Engineering Research Center for Biological Jiaosu, China Three Gorges University, Yichang, 443002, China.
- DOE-Great Lakes Bioenergy Research Center (GLBRC), University of Wisconsin-Madison, Madison, WI, USA.
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29
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Moghaddam AZ, Jazi ME, Allahrasani A, Khazaei M, Ganjali MR, Saeb MR, Vatanpour V. Removal of Chromate and Nitrate Ions from Aqueous Solutions by Co
x
Fe
3‐
x
O
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@silica Hybrid Nanoparticles Decorated with Cross‐Linked Tragacanth Gum: Experiment, Modeling and Optimization. ChemistrySelect 2020. [DOI: 10.1002/slct.202000725] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
| | - Mehdi Erfani Jazi
- Department of ChemistryMississippi State University Mississippi State Mississippi 39762 United States
| | - Ali Allahrasani
- Department of ChemistryCollege of SciencesUniversity of Birjand Birjand 97175-615 Iran
| | - Mohammad Khazaei
- Department of Environmental Health EngineeringSchool of Public Health and Research Center for Health SciencesHamadan University of Medical Sciences Hamadan Iran
| | - Mohammad Reza Ganjali
- Center of Excellence in ElectrochemistrySchool of ChemistryCollege of ScienceUniversity of Tehran Tehran Iran
- Biosensor Research CenterEndocrinology and Metabolism Molecular-Cellular Sciences InstituteTehran University of Medical Sciences Tehran Iran
| | - Mohammad Reza Saeb
- Department of Resin and AdditivesInstitute for Color Science and Technology P.O. Box 16765-654 Tehran Iran
| | - Vahid Vatanpour
- Department of Applied ChemistryFaculty of ChemistryKharazmi University P.O. Box 15719-14911 Tehran Iran
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30
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An Q, Deng S, Xu J, Nan H, Li Z, Song JL. Simultaneous reduction of nitrate and Cr(VI) by Pseudomonas aeruginosa strain G12 in wastewater. ECOTOXICOLOGY AND ENVIRONMENTAL SAFETY 2020; 191:110001. [PMID: 31812281 DOI: 10.1016/j.ecoenv.2019.110001] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2019] [Revised: 11/20/2019] [Accepted: 11/23/2019] [Indexed: 06/10/2023]
Abstract
The interference of toxic heavy metals in the process of microbial aerobic denitrification is a hot issue in industry wastewater treatment in recent years. In this study, a multifunctional aerobic denitrifying bacterium - Pseudomonas aeruginosa G12 isolated from sewage sludge was used to explore the simultaneous removal ability to NO3--N and Cr(VI) in wastewater by a series of batch experiments. The results showed that G12 could effectively remove NO3--N (500 mg L-1) and Cr(VI) (10 mg L-1) by 98% and 93%, respectively. Meanwhile, the study found that the strain G12 had the potential to adapt to the complex external environment, including different carbon resources, nitrogen sources, and the coexisting heavy metals (Mn2+ and Cu2+). The strain G12 also had the considerable tolerance to initial NO3--N (100-700 mg L-1) and Cr(VI) (1-20 mg L-1) concentrations. The instrument analysis methods-Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), and X-ray diffraction (XRD), from the molecular level, further confirmed that the strain G12 could remove NO3--N by aerobic denitrification, and the reduced functional groups (amino group, amide group, hydroxyl group and carboxyl group) on the surface of bacteria could transform Cr(VI) to Cr(III) (mainly CrCl3). This study will offer a promising new microbial resource for nitrogen and Cr(VI) removal in industry wastewater treatment.
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Affiliation(s)
- Qiang An
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China; The Key Laboratory of Eco-environments in Three Gorges Reservoir Region, Chongqing University, Chongqing, 400045, PR China.
| | - Shuman Deng
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Jia Xu
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Hongyan Nan
- School of Environmental Science and Engineering, Shanghai Jiao Tong University, Shanghai, 2002405, PR China
| | - Zheng Li
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
| | - Jia-Li Song
- College of Environment and Ecology, Chongqing University, Chongqing, 400045, PR China
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Ucar D, Yilmaz T, Di Capua F, Esposito G, Sahinkaya E. Comparison of biogenic and chemical sulfur as electron donors for autotrophic denitrification in sulfur-fed membrane bioreactor (SMBR). BIORESOURCE TECHNOLOGY 2020; 299:122574. [PMID: 31865157 DOI: 10.1016/j.biortech.2019.122574] [Citation(s) in RCA: 36] [Impact Index Per Article: 9.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Revised: 12/03/2019] [Accepted: 12/05/2019] [Indexed: 06/10/2023]
Abstract
Two sulfur-oxidizing membrane bioreactors (SMBRs) performing autotrophic denitrification at different HRTs (6-26 h), one supplemented with biogenic elemental sulfur (S0bio) and the other with chemically-synthesized elemental sulfur (S0chem), were compared in terms of nitrate reduction rates, impact on membrane filtration and microbial community composition. Complete denitrification with higher rates (up to 286 mg N-NO3-/L d) was observed in the SMBR supplemented with S0bio (SMBRbio), while nitrate was never completely reduced in the SMBR fed with S0chem (SMBRchem). Trans membrane pressure was higher for SMBRbio due to smaller particle size and colloidal properties of S0bio. Microbial communities in the two SMBRs were similar and dominated by Proteobacteria, with Pleomorphomonas and Thermomonas being the most abundant genera in both bioreactors. This study reveals that S0bio can be effectively used for nitrate removal in autotrophic denitrifying MBRs and results in higher nitrate reduction rates compared to S0chem.
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Affiliation(s)
- Deniz Ucar
- Environmental Engineering Department, Harran University, Osmanbey Campus, 63000 Sanliurfa, Turkey.
| | - Tulay Yilmaz
- Environmental Engineering Department, Harran University, Osmanbey Campus, 63000 Sanliurfa, Turkey
| | - Francesco Di Capua
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio 21, 80125 Naples, Italy
| | - Giovanni Esposito
- Department of Civil, Architectural and Environmental Engineering, University of Naples Federico II, via Claudio 21, 80125 Naples, Italy
| | - Erkan Sahinkaya
- Bioengineering Department, Istanbul Medeniyet University, Uskudar, Istanbul, Turkey
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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: 69] [Impact Index Per Article: 17.3] [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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Hydrilla verticillata-Sulfur-Based Heterotrophic and Autotrophic Denitrification Process for Nitrate-Rich Agricultural Runoff Treatment. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2020; 17:ijerph17051574. [PMID: 32121360 PMCID: PMC7084213 DOI: 10.3390/ijerph17051574] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2020] [Revised: 02/11/2020] [Accepted: 02/25/2020] [Indexed: 11/17/2022]
Abstract
Hydrilla verticillata-sulfur-based heterotrophic and autotrophic denitrification (HSHAD) process was developed in free water surface constructed wetland mesocosms for the treatment of nitrate-rich agricultural runoff with low chemical oxygen demand/total nitrogen (C/N) ratio, whose feasibility and mechanism were extensively studied and compared with those of H. verticillata heterotrophic denitrification (HHD) mesocosms through a 273-day operation. The results showed that the heterotrophic and autotrophic denitrification can be combined successfully in HSHAD mesocosms, and achieve satisfactory nitrate removal performance. The average NO3--N removal efficiency and denitrification rate of HSHAD were 94.4% and 1.3 g NO3--N m-3·d-1 in steady phase II (7-118 d). Most nitrate was reduced by heterotrophic denitrification with sufficient organic carbon in phase I (0-6 d) and II, i.e., the C/N ratio exceeded 4.0, and no significant difference of nitrate removal capacity was observed between HSHAD and HHD mesocosms. During phase III (119-273 d), sulfur autotrophic denitrification gradually dominated the HSHAD process with the C/N ratio less than 4.0, and HSHAD mesocosms obtained higher NO3--N removal efficiency and denitrification rate (79.1% and 1.1 g NO3--N m-3·d-1) than HHD mesocosms (65.3% and 1.0 g NO3--N m-3·d-1). As a whole, HSHAD mesocosms removed 58.8 mg NO3--N more than HHD mesocosms. pH fluctuated between 6.9-9.0 without any pH buffer. In general, HSHAD mesocosms were more stable and efficient than HHD mesocosms for NO3--N removal from agricultural runoff during long-term operation. The denitrificans containing narG (1.67 × 108 ± 1.28 × 107 copies g-1 mixture-soil-1), nirS (8.25 × 107 ± 8.95 × 106 copies g-1 mixture-soil-1), and nosZ (1.56 × 106 ± 1.60 × 105 copies g-1 mixture-soil-1) of litter bags and bottoms in HSHAD were higher than those in HHD, which indicated that the combined heterotrophic and autotrophic denitrification can increase the abundance of denitrificans containing narG, nirS, and nosZ, thus leading to better denitrification performance.
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Su JF, Xue L, Huang TL, Wei L, Gao CY, Wen Q. Performance and microbial community of simultaneous removal of NO 3--N, Cd 2+ and Ca 2+ in MBBR. JOURNAL OF ENVIRONMENTAL MANAGEMENT 2019; 250:109548. [PMID: 31521921 DOI: 10.1016/j.jenvman.2019.109548] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 08/27/2019] [Accepted: 09/06/2019] [Indexed: 06/10/2023]
Abstract
A moving-bed biofilm reactor (MBBR) containing immobilized Acinetobacter sp.CN86 was operated to investigate the simultaneous denitrification, bio-mineralization and cadmium removal performance. Effects of hydraulic residence time (HRT) (4 h, 6 h and 8 h), pH (6.0, 7.0 and 8.0) and influent Cd2+ concentrations (10 mg/L, 30 mg/L and 50 mg/L) were assessed on the simultaneous removal of nitrate, Cd2+ and Ca2+. Results indicate that the highest pollutant removal efficiency (98.33% (1.866 mg/L·h) for NO3--N; 99.36% (1.242 mg/L·h) for Cd2+; 68.80% (15.480 mg/L·h) for Ca2+) was achieved under the conditions of a hydraulic residence time of 8 h, pH of 7.0 and initial Cd2+ concentration of 10 mg/L. Analyses of microbial distribution and community structures showed that Acinetobacter sp.CN86 was the main contributor (occupy 15.3% at the species level) to the effective removal of multiple pollutants in the MBBR. In addition, the main gas and precipitation components in the biofilm reactor were identified by gas chromatography, scanning electron microscope, and X-ray diffraction analyses.
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Affiliation(s)
- Jun Feng Su
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China; State Key Laboratory of Green Building in West China, Xi'an University of Architecture and Technology, Xi'an, 710055, China.
| | - Lei Xue
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Ting Lin Huang
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Li Wei
- State Key Laboratory of Urban Water Resource and Environment, School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin, 150090, China.
| | - Chun Yu Gao
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
| | - Qiong Wen
- School of Environmental and Municipal Engineering, Xi'an University of Architecture and Technology, Xi'an, 710055, China
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Changes of Bacterial Communities in Response to Prolonged Hydrodynamic Disturbances in the Eutrophic Water-Sediment Systems. INTERNATIONAL JOURNAL OF ENVIRONMENTAL RESEARCH AND PUBLIC HEALTH 2019; 16:ijerph16203868. [PMID: 31614843 PMCID: PMC6843157 DOI: 10.3390/ijerph16203868] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/10/2019] [Revised: 09/30/2019] [Accepted: 10/05/2019] [Indexed: 11/17/2022]
Abstract
The effects of hydrodynamic disturbances on the bacterial communities in eutrophic aquatic environments remain poorly understood, despite their importance to ecological evaluation and remediation. This study investigated the evolution of bacterial communities in the water-sediment systems under the influence of three typical velocity conditions with the timescale of 5 weeks. The results demonstrated that higher bacterial diversity and notable differences were detected in sediment compared to water using the 16S rRNA gene sequencing. The phyla Firmicutes and γ-Proteobacteria survived better in both water and sediment under stronger water disturbances. Their relative abundance peaked at 36.0%, 33.2% in water and 38.0%, 43.6% in sediment, respectively, while the phylum Actinobacteria in water had the opposite tendency. Its relative abundance grew rapidly in static control (SC) and peaked at 44.8%, and it almost disappeared in disturbance conditions. These phenomena were caused by the proliferation of genus Exiguobacterium (belonging to Firmicutes), Citrobacter, Acinetobacter, Pseudomonas (belonging to γ-Proteobacteria), and hgcI_clade (belonging to Actinobacteria). The nonmetric multidimensional scaling (NMDS) and Venn analysis also revealed significantly different evolutionary trend in the three water-sediment systems. It was most likely caused by the changes of geochemical characteristics (dissolved oxygen (DO) and nutrients). This kind of study can provide helpful information for ecological assessment and remediation strategy in eutrophic aquatic environments.
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Bayrakdar A, Tilahun E, Çalli B. Simultaneous nitrate and sulfide removal using a bio-electrochemical system. Bioelectrochemistry 2019; 129:228-234. [DOI: 10.1016/j.bioelechem.2019.06.003] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2019] [Revised: 06/05/2019] [Accepted: 06/05/2019] [Indexed: 10/26/2022]
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Dong QY, Wang Z, Shi LD, Lai CY, Zhao HP. Anaerobic methane oxidation coupled to chromate reduction in a methane-based membrane biofilm batch reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:26286-26292. [PMID: 31286367 DOI: 10.1007/s11356-019-05709-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2018] [Accepted: 06/06/2019] [Indexed: 06/09/2023]
Abstract
Chromate can be reduced by methanotrophs in a membrane biofilm reactor (MBfR). In this study, we cultivated a Cr(VI)-reducing biofilm in a methane (CH4)-based membrane biofilm batch reactor (MBBR) under anaerobic conditions. The Cr(VI) reduction rate increased to 0.28 mg/L day when the chromate concentration was ≤ 2.2 mg/L but declined sharply to 0.01 mg/L day when the Cr(VI) concentration increased to 6 mg/L. Isotope tracing experiments showed that part of the 13C-labeled CH4 was transformed to 13CO2, suggesting that the biofilm may reduce Cr(VI) by anaerobic methane oxidation (AnMO). Microbial community analysis showed that a methanogen, i.e., Methanobacterium, dominated in the biofilm, suggesting that this genus is probably capable of carrying out AnMO. The abundance of Methylomonas, an aerobic methanotroph, decreased significantly, while Meiothermus, a potential chromate-reducing bacterium, was enriched in the biofilm. Overall, the results showed that the anaerobic environment inhibited the activity of aerobic methanotrophs while promoting AnMO bacterial enrichment, and high Cr(VI) loading reduced Cr(VI) flux by inhibiting the methane oxidation process.
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Affiliation(s)
- Qiu-Yi Dong
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Zhen Wang
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ling-Dong Shi
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Chun-Yu Lai
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
- Advanced Water Management Centre, The University of Queensland, St. Lucia, 4072, Queensland, Australia.
| | - He-Ping Zhao
- MOE Key Lab of Environmental Remediation and Ecosystem Health, College of Environmental and Resource Science, Zhejiang University, Hangzhou, 310058, China.
- Zhejiang Prov Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China.
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Luo JH, Wu M, Liu J, Qian G, Yuan Z, Guo J. Microbial chromate reduction coupled with anaerobic oxidation of methane in a membrane biofilm reactor. ENVIRONMENT INTERNATIONAL 2019; 130:104926. [PMID: 31228790 DOI: 10.1016/j.envint.2019.104926] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Revised: 06/02/2019] [Accepted: 06/12/2019] [Indexed: 06/09/2023]
Abstract
It has been reported that microbial reduction of sulfate, nitrite/nitrate and iron/manganese could be coupled with anaerobic oxidation of methane (AOM), which plays a significant role in controlling methane emission from anoxic niches. However, little is known about microbial chromate (Cr(VI)) reduction coupling with AOM. In this study, a microbial consortium was enriched via switching nitrate dosing to chromate feeding as the sole electron acceptor under anaerobic condition in a membrane biofilm reactor (MBfR), in which methane was continuously provided as the electron donor through bubble-less hollow fiber membranes. According to long-term reactor operation and chromium speciation analysis, soluble chromate could be reduced into Cr(III) compounds by using methane as electron donor. Fluorescence in situ hybridization and high-throughput 16S rRNA gene amplicon profiling further indicated that after feeding chromate Candidatus 'Methanoperedens' (a known nitrate-dependent anaerobic methane oxidation archaeon) became sole anaerobic methanotroph in the biofilm, potentially responsible for the chromate bio-reduction driven by methane. Two potential pathways of the microbial AOM-coupled chromate reduction were proposed: (i) Candidatus 'Methanoperedens' independently utilizes chromate as electron acceptor to form Cr(III) compounds, or (ii) Candidatus 'Methanoperedens' oxidizes methane to generate intermediates or electrons, which will be utilized to reduce chromate to Cr(III) compounds by unknown chromate reducers synergistically. Our findings suggest a possible link between the biogeochemical chromium and methane cycles.
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Affiliation(s)
- Jing-Huan Luo
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland 4072, Australia; School of Environmental and Chemical Engineering, Shanghai University, 333 Nanchen Road, Shanghai 200444, PR China
| | - Mengxiong Wu
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Jianyong Liu
- School of Environmental and Chemical Engineering, Shanghai University, 333 Nanchen Road, Shanghai 200444, PR China
| | - Guangren Qian
- School of Environmental and Chemical Engineering, Shanghai University, 333 Nanchen Road, Shanghai 200444, PR China
| | - Zhiguo Yuan
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland 4072, Australia
| | - Jianhua Guo
- Advanced Water Management Centre, The University of Queensland, St Lucia, Queensland 4072, Australia.
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Sinharoy A, Pakshirajan K. Heavy metal sequestration by sulfate reduction using carbon monoxide as the sole carbon and energy source. Process Biochem 2019. [DOI: 10.1016/j.procbio.2019.04.002] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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Shi J, Zhang B, Qiu R, Lai C, Jiang Y, He C, Guo J. Microbial Chromate Reduction Coupled to Anaerobic Oxidation of Elemental Sulfur or Zerovalent Iron. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2019; 53:3198-3207. [PMID: 30776217 DOI: 10.1021/acs.est.8b05053] [Citation(s) in RCA: 74] [Impact Index Per Article: 14.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Chromate (Cr(VI)), as one of ubiquitous contaminants in groundwater, has posed a major threat to public health and ecological environment. Although various electron donors (e.g., organic carbon, hydrogen, and methane) have been proposed to drive chromate removal from contaminated water, little is known for microbial chromate reduction coupled to elemental sulfur (S(0)) or zerovalent iron (Fe(0)) oxidation. This study demonstrated chromate could be biologically reduced by using S(0) or Fe(0) as inorganic electron donor. After 60-day cultivation, the sludge achieved a high Cr(VI) removal efficiency of 92.9 ± 1.1% and 98.1 ± 1.2% in two independent systems with S(0) or Fe(0) as the sole electron donor, respectively. The deposited Cr(III) was identified as the main reduction product based on X-ray photoelectron spectroscopy. High-throughput 16S rRNA gene sequencing indicated that Cr(VI) reduction coupled to S(0) or Fe(0) oxidation was mediated synergically by a microbial consortia. In such the consortia, S(0)- or Fe(0)-oxidizing bacteria (e.g., Thiobacillus or Ferrovibrio) could generate volatile fatty acids as metabolites, which were further utilized by chromate-reducing bacteria (e.g., Geobacter or Desulfovibrio) to reduce chromate. Our findings advance our understanding on microbial chromate reduction supported by solid electron donors and also offer a promising process for groundwater remediation.
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Affiliation(s)
- Jiaxin Shi
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution , China University of Geosciences (Beijing) , Beijing 100083 , P. R. China
| | - Baogang Zhang
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution , China University of Geosciences (Beijing) , Beijing 100083 , P. R. China
| | - Rui Qiu
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution , China University of Geosciences (Beijing) , Beijing 100083 , P. R. China
| | - Chunyu Lai
- Advanced Water Management Centre , The University of Queensland , St Lucia , Queensland 4072 , Australia
| | - Yufeng Jiang
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution , China University of Geosciences (Beijing) , Beijing 100083 , P. R. China
| | - Chao He
- School of Water Resources and Environment, MOE Key Laboratory of Groundwater Circulation and Environmental Evolution , China University of Geosciences (Beijing) , Beijing 100083 , P. R. China
| | - Jianhua Guo
- Advanced Water Management Centre , The University of Queensland , St Lucia , Queensland 4072 , Australia
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Zhou S, Zhang Y, Huang T, Liu Y, Fang K, Zhang C. Microbial aerobic denitrification dominates nitrogen losses from reservoir ecosystem in the spring of Zhoucun reservoir. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 651:998-1010. [PMID: 30266057 DOI: 10.1016/j.scitotenv.2018.09.160] [Citation(s) in RCA: 57] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2018] [Revised: 09/11/2018] [Accepted: 09/12/2018] [Indexed: 06/08/2023]
Abstract
The mechanism and factors influencing nitrogen loss in the Zhoucun reservoir were explored during the spring. The results showed that the nitrate and total nitrogen concentration decreased from 1.84 ± 0.01 mg/L and 2.34 ± 0.06 mg/L to 0.06 ± 0.01 mg/L and 0.48 ± 0.09 mg/L, respectively. Meanwhile, the nitrate and total nitrogen removal rate reached 97.02% ± 0.25 and 79.38% ± 3.32, respectively. Moreover, the abundance of nirS gene and aerobic denitrification bacteria increased from 1.04-3.38 × 103 copies/mL and 0.71 ± 0.22 × 102 cfu/mL to 5.36-5.81 × 103 copies/mL and 8.64 ± 2.08 × 103 cfu/mL, respectively. The low MW fractions of DOM (<5 kDa) increased from 0.94 ± 0.02 mg/L in February to 1.51 ± 0.09 mg/L in April. E3/E4 and absorption spectral slope ratio (SR) showed that fulvic acid accounted for the main proportion with autochthonous characteristics. These findings were consistent with the fluorescence components and fluorescence characteristic indices based on EEM-PARAFAC. Meanwhile, the microbial metabolism activity increased significantly from February to April, which contributed to the cycle of nutrients within the reservoir water system. Moreover, the abundance of the bacterial species involved in denitrification (Exiguobacterium, Brevundimonas, Deinococcus, Paracoccus, and Pseudomonas) increased significantly. The relative abundance of KOs related to nitrogen metabolism, were initially increased and then decreased. Specifically, K02567 (napA) represented the main proportion of KOs related to denitrification. The abundance of napA-type denitrifying bacteria (Dechloromonas, Pseudomonas, Azospira, Rhodopseudomonas, Aeromonas, Zobellella, Sulfuritalea, Bradyrhizobium, Achromobacter, Enterobacter, Thauera, and Magnetospirillum) increased significantly during the period of nitrogen loss. Furthermore, the levels of nitrate, T, DO, and AWCD were the most important factors affecting the N-functional bacteria composition. The systematic investigation of the nitrogen loss would provide a theoretical foundation for the remediation of the water reservoir via aerobic denitrification in the future.
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Affiliation(s)
- Shilei Zhou
- Pollution Prevention Biotechnology Laboratory of Hebei Province, School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Yiran Zhang
- Pollution Prevention Biotechnology Laboratory of Hebei Province, School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Tinglin Huang
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China.
| | - Yanfang Liu
- Pollution Prevention Biotechnology Laboratory of Hebei Province, School of Environmental Science and Engineering, Hebei University of Science and Technology, Shijiazhuang 050018, China
| | - Kaikai Fang
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China
| | - Chunhua Zhang
- Shaanxi Key Laboratory of Environmental Engineering, Xi'an University of Architecture & Technology, Xi'an 710055, China
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Chen H, Jin R, Liu G, Tian T, Gu C, Zhou J, Xing D. Effects of sludge lysate for Cr(VI) bioreduction and analysis of bioaugmentation mechanism of sludge humic acid. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2019; 26:5065-5075. [PMID: 30604364 DOI: 10.1007/s11356-018-3917-7] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Accepted: 12/04/2018] [Indexed: 06/09/2023]
Abstract
This study evaluated the effects of sludge lysate (SL) on the anaerobic bioreduction of Cr(VI) and the role of sludge humic acid (SHA) during this process. The results showed that supplement of SL significantly enhanced the efficiency of Cr(VI) bioreduction by 29.61%, in 12 h compared with that of the control without SL. Moreover, SHA exhibited promoting effects on bioreduction of Cr(VI), and the promotion increased with increasing SHA concentrations from 100 to 300 mg/L. In the presence of 300 mg/L SHA, Cr(VI) (98.21 mg/L) was completely reduced after 24 h with a removal rate increased by 34.3% compared with that of the control without SHA. Further investigation on the bioaugmentation mechanism of SHA by studying the nature of SHA and the reaction mechanism between SHA and Cr(VI) revealed that SHA exhibited a strong adsorption ability, which could adsorb and combine with Cr(VI). The adsorption capacity of Cr(VI) by SHA was calculated as 34.4 mg/g with 0.2 g of SHA and 10 mg/L of Cr(VI). It could also act as redox mediators to accelerate the electron transfer between microorganisms and Cr(VI) to promote reduction of Cr(VI). Furthermore, the effects of SL on the microbial community compositions of the anaerobic Cr(VI) bioreduction system were studied. Brachymonas was the primary bacteria at the genus level. The abundance of electroactive bacteria, such as Acinetobacter, Pseudomonas, and Arcobacter, increased in the SL-amended system. These findings expand the versatility of SL and justify wider use of residual activated sludge, which might contribute to the treatment of heavy metal-contaminated wastewater.
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Affiliation(s)
- Hongling Chen
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
- Drainage Management Office, Tongliao Municipal Commission of Housing Urban-Rural Development, Tongliao, 028000, China
| | - Ruofei Jin
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
| | - Guangfei Liu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Tian Tian
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Chen Gu
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Jiti Zhou
- Key Laboratory of Industrial Ecology and Environmental Engineering, Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Defeng Xing
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin, 150090, China.
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Liao R, Miao Y, Li J, Li Y, Wang Z, Du J, Li Y, Li A, Shen H. Temperature dependence of denitrification microbial communities and functional genes in an expanded granular sludge bed reactor treating nitrate-rich wastewater. RSC Adv 2018; 8:42087-42094. [PMID: 35558806 PMCID: PMC9092073 DOI: 10.1039/c8ra08256a] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2018] [Accepted: 11/28/2018] [Indexed: 11/21/2022] Open
Abstract
The temperature dependence of denitrification was investigated for high nitrate nitrogen denitrification in an expanded granular sludge bed (EGSB) reactor. The optimal reaction temperatures were 15-35 °C in which nearly complete denitrification was achieved with the removal of COD maintained over 80%. Nitrite accumulation was observed at 10 °C indicating the incomplete denitrification at low temperature. However, almost complete denitrification was even accomplished as high as 52 °C. High-throughput sequencing detected a total of 84 bacterial genera and 7 phyla, and temperature variation resulted in the shift of microbial community structure and diversity. Proteobacteria thrived while Firmicutes and Bacteroidetes were inhibited by temperature stress. The predominance of Halomonas and the significant decrease of Azoarcus at low temperature indicated a more important role of these two genera in denitrification in an EGSB reactor. The results of qPCR indicated that temperature exerted effects on the abundance of denitrification function genes, nirK, nirS, narG, and nosZ, due to the shift of the bacterial community. This study provided a comprehensive understanding of temperature effects on the denitrification process in an EGSB reactor treating high concentration nitrate wastewater.
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Affiliation(s)
- Runhua Liao
- School of Materials Science and Engineering, Jingdezhen Ceramic Institute Jingdezhen 333403 China
- Department of Mechanical & Nuclear Engineering, Virginia Commonwealth University Richmond VA 23219 USA
| | - Yu Miao
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China +86-025-89680377
| | - Jun Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China +86-025-89680377
| | - Yan Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China +86-025-89680377
| | - Zhu Wang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China +86-025-89680377
| | - Jie Du
- School of Materials Science and Engineering, Jingdezhen Ceramic Institute Jingdezhen 333403 China
| | - Yueming Li
- School of Materials Science and Engineering, Jingdezhen Ceramic Institute Jingdezhen 333403 China
| | - Aimin Li
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University Nanjing 210023 China +86-025-89680377
| | - Huijuan Shen
- School of Materials Science and Engineering, Jingdezhen Ceramic Institute Jingdezhen 333403 China
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Fan C, Wang P, Zhou W, Wu S, He S, Huang J, Cao L. The influence of phosphorus on the autotrophic and mixotrophic denitrification. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 643:127-133. [PMID: 29936156 DOI: 10.1016/j.scitotenv.2018.06.185] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/28/2018] [Revised: 06/14/2018] [Accepted: 06/14/2018] [Indexed: 06/08/2023]
Abstract
Autotrophic and mixotrophic denitrification, two approaches of biological denitrification, have drawn more and more attention among the techniques to remove nitrogen from the aquatic environment. This study investigated the influence of phosphorus on the denitrification performance and bacterial community structure in the autotrophic and mixotrophic denitrification reactors. The activity test was applied to evaluate the variation of denitrification activity of autotrophic and mixotrophic sludge before and after phosphorus addition. High-throughput sequencing was used to analyze the change of bacterial community structure. The results showed that NO3--N removal efficiency of autotrophic and mixotrophic denitrification process increased by 40 and 35%, respectively, after phosphorus addition. The sludge denitrification activity of autotrophic and mixotrophic sludge was enhanced significantly. And phosphorus addition could greatly improve the proportion of denitrifying bacteria in both autotrophic (from 11.83 to 64.31%) and mixotrophic denitrifying sludge (from 13.59 to 45.12%). Overall, phosphorus addition could greatly improve the autotrophic and mixotrophic denitrification ability in the phosphorus deficient surface water.
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Affiliation(s)
- Chunzhen Fan
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China; School of Agriculture and Biology, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China
| | - Peiqi Wang
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China; Shanghai Solid Waste Disposal Co., Ltd., No. 2491, Jiazhu Highway, Jiading District, Shanghai 201815, China
| | - Weili Zhou
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China.
| | - Suqing Wu
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China
| | - Shengbing He
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China
| | - Jungchen Huang
- School of Environmental Science and Engineering, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China
| | - Linkui Cao
- School of Agriculture and Biology, Shanghai Jiaotong University, No. 800, Dongchuan Road, Minhang District, Shanghai 200240, China
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45
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Kiran Kumar Reddy G, Nancharaiah YV. Sustainable bioreduction of toxic levels of chromate in a denitrifying granular sludge reactor. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2018; 25:1969-1979. [PMID: 29105040 DOI: 10.1007/s11356-017-0600-3] [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: 08/18/2017] [Accepted: 10/24/2017] [Indexed: 06/07/2023]
Abstract
Biological removal of chromate [Cr(VI)] in the presence or absence of nitrate by granular sludge biofilms was investigated in batch experiments and in a sequencing batch reactor (SBR). Denitrifying granular sludge cultivated from activated sludge was able to directly reduce Cr(VI) in the presence of an electron donor. Bioreduction was dependent on the initial Cr(VI) and the granular sludge concentrations. Bioreduction of Cr(VI) was followed by Cr(III) precipitation or entrapment in the granular sludge which was corroborated with decrease in total soluble Cr and increase in inorganic content of biomass. Batch experiments revealed that Cr(VI) addition has no major influence on high-strength nitrate (3000 mg L-1) denitrification, but nitrite denitrification was slowed-down. However, SBR experiment demonstrated successful denitrification as well as Cr(VI) removal due to enrichment of Cr(VI)-tolerant denitrifying bacteria. In fact, stable SBR performance in terms of complete and sustained removal of 0.05, 0.1, 0.2, 0.3, 0.5 and 0.75 mM Cr(VI) and denitrification of 3000 mg L-1 was observed during 2 months of operation. Active biomass and electron donor-dependent Cr(VI) removal, detection of Cr(III) in the biomass and recovery of ~ 92% of the Cr from the granular sludge biofilms confirms bioreduction followed by precipitation or entrapment of Cr(III) as the principal chromate removal mechanism. Metagenomic bacterial community analysis showed enrichment of Halomonas sp. in denitrifying granular sludge performing either denitrification or simultaneous reduction of nitrate and chromate.
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Affiliation(s)
- G Kiran Kumar Reddy
- Water and Steam Chemistry Division, Bhabha Atomic Research Centre, Kalpakkam, 603102, India
- Homi Bhabha National Institute, Anushakti Nagar Complex, Mumbai, 400 094, India
| | - Y V Nancharaiah
- Water and Steam Chemistry Division, Bhabha Atomic Research Centre, Kalpakkam, 603102, India.
- Homi Bhabha National Institute, Anushakti Nagar Complex, Mumbai, 400 094, India.
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Xu D, Xiao E, Xu P, Lin L, Zhou Q, Xu D, Wu Z. Bacterial community and nitrate removal by simultaneous heterotrophic and autotrophic denitrification in a bioelectrochemically-assisted constructed wetland. BIORESOURCE TECHNOLOGY 2017; 245:993-999. [PMID: 28946208 DOI: 10.1016/j.biortech.2017.09.045] [Citation(s) in RCA: 45] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2017] [Revised: 09/04/2017] [Accepted: 09/06/2017] [Indexed: 06/07/2023]
Abstract
To enhance nitrate removal in constructed wetlands (CWs), a bioelectrochemically-assisted CW (BECW) integrating a three-dimensional biofilm-electrode reactor (3D-BER) into the CW was evaluated for the effectiveness of combined autotrophic and heterotrophic denitrification in the presence of organic matter and applied current. The effects of COD/N ratios on nitrate removal were investigated, and the bacterial communities in the granular active carbon (GAC) and graphite felt (GF) in the reactor's cathode region were compared. The highest NO3--N and TN removal efficiencies of 91.3±7.2% and 68.8±7.9% were obtained at the COD/N ratio of 5. According to the results of high-throughput sequencing analysis, sample GAC was enriched with a high abundance of Pseudomonas (17.29%) capable of autotrophic and heterotrophic denitrification, whereas autotrophic bacteria Thiobacillus (43.94%) was predominant in sample GF. The synergy between heterotrophic and autotrophic denitrification bacteria is believed to cause the high and stable nitrogen removal performance.
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Affiliation(s)
- Dan Xu
- College of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, PR China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Enrong Xiao
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China.
| | - Peng Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China; Graduate University of Chinese Academy of Sciences, Beijing 100039, PR China
| | - Lili Lin
- College of Resources and Environmental Engineering, Wuhan University of Technology, Wuhan 430070, PR China; State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Qiaohong Zhou
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Dong Xu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
| | - Zhenbin Wu
- State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan 430072, PR China
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Zhong L, Lai CY, Shi LD, Wang KD, Dai YJ, Liu YW, Ma F, Rittmann BE, Zheng P, Zhao HP. Nitrate effects on chromate reduction in a methane-based biofilm. WATER RESEARCH 2017; 115:130-137. [PMID: 28273443 DOI: 10.1016/j.watres.2017.03.003] [Citation(s) in RCA: 58] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/29/2016] [Revised: 02/27/2017] [Accepted: 03/01/2017] [Indexed: 06/06/2023]
Abstract
The effects of nitrate (NO3-) on chromate (Cr(VI)) reduction in a membrane biofilm reactor (MBfR) were studied when CH4 was the sole electron donor supplied with a non-limiting delivery capacity. A high surface loading of NO3- gave significant and irreversible inhibition of Cr(VI) reduction. At a surface loading of 500 mg Cr/m2-d, the Cr(VI)-removal percentage was 100% when NO3- was absent (Stage 1), but was dramatically lowered to < 25% with introduction of 280 mg N m-2-d NO3- (Stage 2). After ∼50 days operation in Stage 2, the Cr(VI) reduction recovered to only ∼70% in Stage 3, when NO3- was removed from the influent; thus, NO3- had a significant long-term inhibition effect on Cr(VI) reduction. Weighted PCoA and UniFrac analyses proved that the introduction of NO3- had a strong impact on the microbial community in the biofilms, and the changes possibly were linked to the irreversible inhibition of Cr(VI) reduction. For example, Meiothermus, the main genus involved in Cr(VI) reduction at first, declined with introduction of NO3-. The denitrifier Chitinophagaceae was enriched after the addition of NO3-, while Pelomonas became important when nitrate was removed, suggesting its potential role as a Cr(VI) reducer. Moreover, introducing NO3- led to a decrease in the number of genes predicted (by PICRUSt) to be related to chromate reduction, but genes predicted to be related to denitrification, methane oxidation, and fermentation increased.
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Affiliation(s)
- Liang Zhong
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Chun-Yu Lai
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ling-Dong Shi
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Kai-Di Wang
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Yu-Jie Dai
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Yao-Wei Liu
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China
| | - Fang Ma
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
| | - Bruce E Rittmann
- Biodesign Swette Center for Environmental Biotechnology, Arizona State University, P.O. Box 875701, Tempe, AZ 85287-5701, USA
| | - Ping Zheng
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China
| | - He-Ping Zhao
- Department of Environmental Engineering, College of Environmental and Resource Science, Zhejiang University, Hangzhou, China; Zhejiang Province Key Lab Water Pollut Control & Envi, Zhejiang University, Hangzhou, Zhejiang, China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, China.
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48
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Zhai S, Zhao Y, Ji M, Qi W. Simultaneous removal of nitrate and chromate in groundwater by a spiral fiber based biofilm reactor. BIORESOURCE TECHNOLOGY 2017; 232:278-284. [PMID: 28237899 DOI: 10.1016/j.biortech.2017.01.076] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2016] [Revised: 01/19/2017] [Accepted: 01/22/2017] [Indexed: 06/06/2023]
Abstract
A spiral fiber based biofilm reactor was developed to remove nitrate and chromate simultaneously. The denitrification and Cr(VI) removal efficiency was evaluated with synthetic groundwater (NO3--N=50mg/L) under different Cr(VI) concentrations (0-1.0mg/L), carbon nitrogen ratios (C/N) (0.8-1.2), hydraulic retention times (HRT) (2-16h) and initial pHs (4-10). Nitrate and Cr(VI) were completely removed without nitrite accumulation when the Cr(VI) concentration was lower than 0.4mg/L. As Cr(VI) up to 1.0mg/L, the system was obviously inhibited, but it recovered rapidly within 6days due to the strong adaption and domestication of microorganisms in the biofilm reactor. The results demonstrated that high removal efficiency of nitrate (≥99%) and Cr(VI) (≥95%) were achieved at lower C/N=0.9, HRT=8h, initial pH=7, and Cr(VI)=1.0mg/L. The technology proposed in present study can be alternative for simultaneous removal of co-contaminants in groundwater.
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Affiliation(s)
- Siyuan Zhai
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
| | - Yinxin Zhao
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China; Tianjin Engineering Research Center of Urban River Eco-Purification Technology, Tianjin 300350, China.
| | - Min Ji
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China; Tianjin Engineering Research Center of Urban River Eco-Purification Technology, Tianjin 300350, China
| | - Wenfang Qi
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300350, China
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Sahinkaya E, Yurtsever A, Ucar D. A novel elemental sulfur-based mixotrophic denitrifying membrane bioreactor for simultaneous Cr(VI) and nitrate reduction. JOURNAL OF HAZARDOUS MATERIALS 2017; 324:15-21. [PMID: 26906435 DOI: 10.1016/j.jhazmat.2016.02.032] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/15/2015] [Revised: 01/31/2016] [Accepted: 02/12/2016] [Indexed: 06/05/2023]
Abstract
This study aims at investigating the simultaneous nitrate and chromate reduction by combining the advantages of sulfur-based autotrophic denitrification, heterotrophic denitrification and membrane bioreactor (MBR) technologies. A laboratory-scale MBR equipped with hydrophilic flat sheet polyethersulfone (PES) membranes (0.45μm) was used to evaluate the performance of mixotrophic denitrification at varying nitrate and Cr(VI) concentrations. Methanol was supplied at C/N (mg methanol/mg NO3--N) ratio of 1.33. In the absence of Cr(VI), almost complete denitrification of 50mg/L NO3--N was obtained and the methanol requirement (3.60±0.9mg COD/(mg NO3--N)) for heterotrophic denitrifiers, was quite close to the theoretical value (3.7mg COD/(mg NO3--N)). Around 54% of the influent nitrate was denitrified by heterotrophs and the rest (56%) was denitrified by autotrophic sulfur oxidizers. The effluent sulfate averaged around 200mg/L, which was below than the theoretical sulfate concentration if autotrophic denitrification process was used alone. Autotrophic denitrification activity completely ceased at 5mg/L Cr(VI), but heterotrophic denitrification did not show any inhibition. Almost complete chromate and nitrate reduction was observed at 1mg/L Cr(VI). MBR was operated for around 200days and a weekly physical membrane cleaning was enough at a flux of 15 LMH.
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Affiliation(s)
- Erkan Sahinkaya
- Istanbul Medeniyet University, Bioengineering Department, Goztepe, Istanbul, Turkey.
| | - Adem Yurtsever
- Yildiz Technical University, Department of Environmental Engineering, Istanbul, Turkey
| | - Deniz Ucar
- Harran University, Environmental Engineering Department, Osmanbey Campus, 63000 Sanliurfa, Turkey
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50
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Mora Collazos A, Bravo Montaño E. Aislamiento de microorganismos electrogénicos con potencial para reducir cromo hexavalente. ACTA BIOLÓGICA COLOMBIANA 2017. [DOI: 10.15446/abc.v22n1.57189] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022] Open
Abstract
Se realizó el aislamiento de microorganismos cultivables a partir de la biopelícula formada sobre el ánodo de una celda de combustible microbiana puesta en operación durante 30 días; los microorganismos aislados fueron evaluados en su capacidad de producir energía en celdas de combustible microbianas y de reducir el cromo hexavalente, Cr (VI). Se aislaron cinco microorganismos, los cuales fueron caracterizados mediante análisis del gen del ARNr 16S, el cual ubicó a los microorganismos en cuatro géneros bacterianos: Exiguobacterium (CrMFC1), Acinetobacter (CrMFC2), Aeromonas (CrMFC3 y CrMFC5), y Serratia (CrMFC4). Todas las cepas aisladas mostraron actividad electrogénica y capacidad para reducir cromo hexavalente; la cepa de Acinetobacter CrMFC2 mostró el mejor desempeño electroquímico al registrar una densidad de potencia máxima de 18,61 mW/m2; las demás cepas mostraron valores de densidad de potencia máxima entre 4,6 mW/m2 y 7.1 mW/m2. Las cepas de Aeromonas CrMFC5 y Exiguobacterium CrMFC1 mostraron las mejores tasas de reducción de cromo al ser capaces de reducir el 100% del Cr (VI) en menos de 24 horas, destacándose la cepa de Aeromonas CrMFC5 la cual redujo el 100 % de Cr (VI) en 10 horas; las demás cepas redujeron el 100 % del contaminante al cabo de 28 a 30 horas. Los microorganismos aislados en este estudio son escasamente conocidos por su capacidad electrogénica y de reducir el Cr (VI); no obstante, se muestran promisorios para su utilización en sistemas mixtos que involucren la producción de energía acoplada a sistema de biorremediación de aguas contaminadas con cromo.
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