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Zhang L, Ji P, Song R, Li J, Qin K, Xu G. Synergistic activation of persulfate by a manganese cobalt oxide/reduced graphene oxide nanocomposite with enhanced degradation of trichloroethylene. RSC Adv 2023; 13:28984-28992. [PMID: 37799304 PMCID: PMC10548434 DOI: 10.1039/d3ra03834c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/08/2023] [Accepted: 08/22/2023] [Indexed: 10/07/2023] Open
Abstract
Advanced oxidation technology based on persulfate is one of the most reliable and effective technologies for the degradation of wastewater, however the key lies in developing highly efficient catalysts to activate persulfate. Herein, manganese cobalt oxide/reduced graphene oxide (MnCo2O4/rGO) nanocomposites were successfully synthesized via a facile solvothermal method and employed as a highly efficient catalyst to active persulfate for the degradation of trichloroethylene (TCE). The rGO nanosheets have large surface areas, which can increase the contact area with reactants and make the degradation more efficient. Additionally, the MnCo2O4 nanoparticles are in situ grown on the surface of ultrathin rGO nanosheets, endowing the material with high structural porosity and fast transport channels, and are beneficial for the improvement of catalytic sites and the transport of catalysis-relevant species. More importantly, the close contact between MnCo2O4 nanoparticles and rGO nanosheets synergistically favors the electron transfer, thereby accelerating the electron transfer, improving the activation efficiency, and promoting the generation of sulfate radicals (·SO4-). rGO can also reduce the spillover of metal ions. The kinetics model and degradation mechanism of the nanocomposites are also proposed.
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Affiliation(s)
- Lu Zhang
- School of Environmental and Chemical Engineering, Shanghai University 99 Shangda Road Shanghai 200444 P. R. China
- Key Laboratory of Organic Compound Pollution Control Engineering, Ministry of Education Shanghai 200444 P. R. China
| | - Pengfei Ji
- School of Environmental and Chemical Engineering, Shanghai University 99 Shangda Road Shanghai 200444 P. R. China
| | - Rui Song
- School of Environmental and Chemical Engineering, Shanghai University 99 Shangda Road Shanghai 200444 P. R. China
| | - Jiayuan Li
- School of Environmental and Chemical Engineering, Shanghai University 99 Shangda Road Shanghai 200444 P. R. China
| | - Kaifeng Qin
- Key Laboratory of Organic Compound Pollution Control Engineering, Ministry of Education Shanghai 200444 P. R. China
| | - Gang Xu
- School of Environmental and Chemical Engineering, Shanghai University 99 Shangda Road Shanghai 200444 P. R. China
- Key Laboratory of Organic Compound Pollution Control Engineering, Ministry of Education Shanghai 200444 P. R. China
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Gaio J, Lora NL, Iltchenco J, Magrini FE, Paesi S. Seasonal characterization of the prokaryotic microbiota of full-scale anaerobic UASB reactors treating domestic sewage in southern Brazil. Bioprocess Biosyst Eng 2023; 46:69-87. [PMID: 36401655 DOI: 10.1007/s00449-022-02814-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/26/2022] [Accepted: 11/12/2022] [Indexed: 11/21/2022]
Abstract
Upflow Anaerobic Sludge Blanket (UASB) reactors are alternatives in the anaerobic treatment of sanitary sewage in different parts of the world; however, in temperate environments, they are subject to strong seasonal influence. Understanding the dynamics of the microbial community in these systems is essential to propose operational alternatives, improve projects and increase the quality of treated effluents. In this study, for one year, high-performance sequencing, associated with bioinformatics tools for taxonomic annotation and functional prediction was used to characterize the microbial community present in the sludge of biodigesters on full-scale, treating domestic sewage at ambient temperature. Among the most representative phyla stood out Desulfobacterota (20.21-28.64%), Proteobacteria (7.48-24.90%), Bacteroidota (10.05-18.37%), Caldisericota (9.49-17.20%), and Halobacterota (3.23-6.55%). By performing a Canonical Correspondence Analysis (CCA), Methanolinea was correlated to the efficiency in removing Chemical Oxygen Demand (COD), Bacteroidetes_VadinHA17 to the production of volatile fatty acids (VFAs), and CI75cm.2.12 at temperature. On the other hand, Desulfovibrio, Spirochaetaceae_uncultured, Methanosaeta, Lentimicrobiaceae_unclassified, and ADurb.Bin063-1 were relevant in shaping the microbial community in a co-occurrence network. Diversity analyses showed greater richness and evenness for the colder seasons, possibly, due to the lesser influence of dominant taxa. Among the principal metabolic functions associated with the community, the metabolism of proteins and amino acids stood out (7.74-8.00%), and the genes related to the synthesis of VFAs presented higher relative abundance for the autumn and winter. Despite the differences in diversity and taxonomic composition, no significant changes were observed in the efficiency of the biodigesters.
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Affiliation(s)
- Juliano Gaio
- Molecular Diagnostic Laboratory (LDM), Biotechnology Institute (IB), University of Caxias Do Sul (UCS), Caxias Do Sul, RS, 95070-560, Brazil.
| | - Naline Laura Lora
- Molecular Diagnostic Laboratory (LDM), Biotechnology Institute (IB), University of Caxias Do Sul (UCS), Caxias Do Sul, RS, 95070-560, Brazil
| | - Janaína Iltchenco
- Molecular Diagnostic Laboratory (LDM), Biotechnology Institute (IB), University of Caxias Do Sul (UCS), Caxias Do Sul, RS, 95070-560, Brazil
| | - Flaviane Eva Magrini
- Molecular Diagnostic Laboratory (LDM), Biotechnology Institute (IB), University of Caxias Do Sul (UCS), Caxias Do Sul, RS, 95070-560, Brazil
| | - Suelen Paesi
- Molecular Diagnostic Laboratory (LDM), Biotechnology Institute (IB), University of Caxias Do Sul (UCS), Caxias Do Sul, RS, 95070-560, Brazil
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Meng Q, Li P, Qu J, Liu Y, Wang Y, Chen Z, Zhang Y. Study on the community structure and function of anaerobic granular sludge under trichloroethylene stress. ECOTOXICOLOGY (LONDON, ENGLAND) 2021; 30:1408-1418. [PMID: 33471269 DOI: 10.1007/s10646-020-02343-9] [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] [Accepted: 12/28/2020] [Indexed: 06/12/2023]
Abstract
Trichloroethylene (TCE) is one of the most common groundwater pollutants. It is carcinogenic, teratogenic, mutagenic and poses a serious threat to human health and the environment. Therefore, reducing the environmental toxicity of TCE is of great significance. Anaerobic sludge was cultured and acclimated in an upflow anaerobic sludge blanket (UASB) reactor in this study. The Chemical Oxygen Demand (COD) concentration of the influent was approximately 2500 mg L-1, and the TCE concentration of the influent ranged from 1.46 mg L-1 to 73 mg L-1. After biodegradation of the anaerobic microflora, the COD removal rate was approximately 85%, and the TCE removal rate was over 85%. The microbial community of anaerobic sludge was analysed by 16 S rDNA clone libray and 454 high-throughput sequencing. Through analysis of the sequencing results, we found that there were a variety of acid-forming bacteria, anaerobic dechlorinating bacteria, and methanogenic bacteria. Based on the analysis of microflora function, it was speculated that the TCE metabolic pathway took place in UASB reactors. Desulfovibrio and Syntrophobacter provided an anaerobic environment, and acid-forming bacteria metabolise organic compounds into hydrogen. With Dehalobacter and Geobacter, TCE as an electron acceptor is dechlorinated and reduced under the anaerobic environment, in which hydrogen acts as an electron donor. By this, we clarified the metabolic pathway for improving TCE bioremediation.
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Affiliation(s)
- Qingjuan Meng
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China
| | - Pengfei Li
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China
| | - Jianhua Qu
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China
| | - Ying Liu
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China
| | - Yifan Wang
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China
| | - Zhaobo Chen
- College of Environment and Resources, Dalian Minzu University, 18 Liaohe West Road, Dalian, 116600, China
| | - Ying Zhang
- College of Resources and Environment, Northeast Agricultural University, Harbin, 150030, China.
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Khan N, Khan MD, Sabir S, Nizami AS, Anwer AH, Rehan M, ZainKhan M. Deciphering the effects of temperature on bio-methane generation through anaerobic digestion. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:29766-29777. [PMID: 31873899 DOI: 10.1007/s11356-019-07245-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2019] [Accepted: 12/02/2019] [Indexed: 06/10/2023]
Abstract
Anaerobic digestion (AD) is a sustainable wastewater treatment technology which facilitates energy, nutrient, and water recovery from organic wastes. The agricultural and industrial wastes are suitable substrates for the AD, as they contain a high level of biodegradable compounds. The aim of this study was to examine the AD of three different concentrations of phenol (100, 200, and 300 mg/L) containing wastewater with and without co-substrate (acetate) at four different temperatures (25, 35, 45, and 55 °C) to produce methane (CH4)-enriched biogas. It was observed that the chemical oxygen demand (COD) and phenol removal efficiencies of up to 76% and 72%, respectively, were achieved. The CH4 generation was found higher in anaerobic batch reactors (ABRs) using acetate as co-substrate, with the highest yield of 189.1 μL CH4 from 500 μL sample injected, obtained using 200 mg/L of phenol at 35 °C. The results revealed that the performance of ABR in terms of degradation efficiency, COD removal, and biogas generation was highest at 35 °C followed by 55, 45, and 25 °C indicating 35 °C to be the optimum temperature for AD of phenolic wastewater with maximum energy recovery. Scanning electron microscopy (SEM) revealed that the morphology of the anaerobic sludge depends greatly on the temperature at which the system is maintained which in turn affects the performance and degradation of toxic contaminants like phenol. It was observed that the anaerobic sludge maintained at 35 °C showed uniform channels leading to higher permeability through enhanced mass transfer to achieve higher degradation rates. However, the denser sludge as in the case of 55 °C showed lesser permeability leading to limited transfer and thus reduced treatment. Quantitative real-time PCR (qPCR) analysis revealed a more noteworthy change in the population of the microbial communities due to temperature than the presence of phenol with the methanogens being the dominating species at 35 °C. The findings suggest that the planned operation of the ABR could be a promising choice for CH4-enriched biogas and COD removal from phenolic wastewater.
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Affiliation(s)
- Nishat Khan
- Department of Chemistry, Environmental Research Laboratory, Aligarh Muslim University, Aligarh, Uttar Pradesh, 202002, India
| | - Mohammad Danish Khan
- Department of Chemistry, Environmental Research Laboratory, Aligarh Muslim University, Aligarh, Uttar Pradesh, 202002, India
| | - Suhail Sabir
- Department of Chemistry, Environmental Research Laboratory, Aligarh Muslim University, Aligarh, Uttar Pradesh, 202002, India
| | - Abdul-Sattar Nizami
- Sustainable Development Study Centre, Government College University, Lahore, Pakistan.
| | - Abdul Hakeem Anwer
- Department of Chemistry, Environmental Research Laboratory, Aligarh Muslim University, Aligarh, Uttar Pradesh, 202002, India
| | - Mohammad Rehan
- Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohammad ZainKhan
- Department of Chemistry, Environmental Research Laboratory, Aligarh Muslim University, Aligarh, Uttar Pradesh, 202002, India.
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Paulo LM, Castilla-Archilla J, Ramiro-Garcia J, Escamez-Picón JA, Hughes D, Mahony T, Murray M, Wilmes P, O'Flaherty V. Microbial Community Redundancy and Resilience Underpins High-Rate Anaerobic Treatment of Dairy-Processing Wastewater at Ambient Temperatures. Front Bioeng Biotechnol 2020; 8:192. [PMID: 32232038 PMCID: PMC7082317 DOI: 10.3389/fbioe.2020.00192] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/17/2019] [Accepted: 02/27/2020] [Indexed: 11/25/2022] Open
Abstract
High-rate anaerobic digestion (AD) is a reliable, efficient process to treat wastewaters and is often operated at temperatures exceeding 30°C, involving energy consumption of biogas in temperate regions, where wastewaters are often discharged at variable temperatures generally below 20°C. High-rate ambient temperature AD, without temperature control, is an economically attractive alternative that has been proven to be feasible at laboratory-scale. In this study, an ambient temperature pilot scale anaerobic reactor (2 m3) was employed to treat real dairy wastewater in situ at a milk processing plant, at organic loading rates of 1.3 ± 0.6 to 10.6 ± 3.7 kg COD/m3/day and hydraulic retention times (HRT) ranging from 36 to 6 h. Consistent high levels of COD removal efficiencies, ranging from 50 to 70% for total COD removal and 70 to 84% for soluble COD removal, were achieved during the trial. Within the reactor biomass, stable active archaeal populations were observed, consisting mainly of Methanothrix (previously Methanosaeta) species, which represented up to 47% of the relative abundant active species in the reactor. The decrease in HRT, combined with increases in the loading rate had a clear effect on shaping the structure and composition of the bacterial fraction of the microbial community, however, without affecting reactor performance. On the other hand, perturbances in influent pH had a strong impact, especially when pH went higher than 8.5, inducing shifts in the microbial community composition and, in some cases, affecting negatively the performance of the reactor in terms of COD removal and biogas methane content. For example, the main pH shock led to a drop in the methane content to 15%, COD removals decreased to 0%, while the archaeal population decreased to ~11% both at DNA and cDNA levels. Functional redundancy in the microbial community underpinned stable reactor performance and rapid reactor recovery after perturbations.
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Affiliation(s)
- Lara M Paulo
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,Dairy Processing Technology Centre (DPTC), Limerick, Ireland
| | - Juan Castilla-Archilla
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,Dairy Processing Technology Centre (DPTC), Limerick, Ireland
| | - Javier Ramiro-Garcia
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - José Antonio Escamez-Picón
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,Dairy Processing Technology Centre (DPTC), Limerick, Ireland
| | - Dermot Hughes
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,NVP Energy Ltd., Galway Technology & Business Centre, Galway, Ireland
| | - Thérèse Mahony
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,Dairy Processing Technology Centre (DPTC), Limerick, Ireland
| | - Michael Murray
- NVP Energy Ltd., Galway Technology & Business Centre, Galway, Ireland
| | - Paul Wilmes
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Vincent O'Flaherty
- Microbiology, School of Natural Sciences and Ryan Institute, NUI Galway, Galway, Ireland.,Dairy Processing Technology Centre (DPTC), Limerick, Ireland
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Acetotrophic Activity Facilitates Methanogenesis from LCFA at Low Temperatures: Screening from Mesophilic Inocula. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2019; 2019:1751783. [PMID: 31191117 PMCID: PMC6525847 DOI: 10.1155/2019/1751783] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 10/14/2018] [Revised: 02/14/2019] [Accepted: 04/03/2019] [Indexed: 12/04/2022]
Abstract
The inoculum source plays a crucial role in the anaerobic treatment of wastewaters. Lipids are present in various wastewaters and have a high methanogenic potential, but their hydrolysis results in the production of long chain fatty acids (LCFAs) that are inhibitory to anaerobic microorganisms. Screening of inoculum for the anaerobic treatment of LCFA-containing wastewaters has been performed at mesophilic and thermophilic conditions. However, an evaluation of inocula for producing methane from LCFA-containing wastewater has not yet been conducted at low temperatures and needs to be undertaken. In this study, three inocula (one granular sludge and two municipal digester sludges) were assessed for methane production from LCFA-containing synthetic dairy wastewater (SDW) at low temperatures (10 and 20°C). A methane yield (based on mL-CH4/g-CODadded) of 86-65% with acetate and 45-20% with SDW was achieved within 10 days using unacclimated granular sludge, whereas the municipal digester sludges produced methane only at 20°C but not at 10°C even after 200 days of incubation. The acetotrophic activity in the inoculum was found to be crucial for methane production from LCFA at low temperatures, highlighting the role of Methanosaeta (acetoclastic archaea) at low temperatures. The presence of bacterial taxa from the family Syntrophaceae (Syntrophus and uncultured taxa) in the inoculum was found to be important for methane production from SDW at 10°C. This study suggests the evaluation of acetotrophic activity and the initial microbial community characteristics by high-throughput amplicon sequencing for selecting the inoculum for producing methane at low temperatures (up to 10°C) from lipid-containing wastewaters.
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Santana-Santos MA, Ordaz A, Jan-Roblero J, Bastida González F, Zárate Segura PB, Guerrero-Barajas C. Tolerance of a sulfidogenic sludge to trichloroethylene at microcosms level as a basis for a long-term operation of reactors designed for its biodegradation. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2019; 54:461-471. [PMID: 30676262 DOI: 10.1080/10934529.2019.1567157] [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: 10/15/2018] [Revised: 12/13/2018] [Accepted: 12/21/2018] [Indexed: 06/09/2023]
Abstract
Trichloroethylene (TCE) is known as a toxic organic compound found as a pollutant in water streams around the world. The ultimate goal of the present work was to determine the TCE concentration that would be feasible to biodegrade on a long-term basis by a sulfidogenic sludge while maintaining sulfate reducing activity (SRA). Microcosms were prepared with sulfidogenic sludge obtained from a stabilized sulfidogenic UASB and amended with different TCE concentrations (100-300 µM) and two different proportions of volatile fatty acids (VFA) acetate, propionate and butyrate at COD of 2.5:1:1 and 1:1:1, respectively to evaluate the tolerance of the sludge. The overall results suggested that the continuous exposure of the microorganisms to TCE leads to inhibition of SRA; nonetheless, the SRA can be recovered after adequate supplementation of carbon sources and sulfate. The most suitable TCE concentration to operate on a long-term basis while preserving SRA was 26-35 mg L-1 (200-260 µM). A low level of expression of the mRNA of the sulfite reductase subunit alpha (dsrA) gene was obtained in the presence of the TCE and its intermediate products. This gene was associated to SRB belonging to the genera Desulfovibrio, Desulfosalsimonas, Desulfotomaculum, Desulfococcus, Desulfatiglans and Desulfomonas.
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Affiliation(s)
- Mario Alberto Santana-Santos
- a Laboratorio de Biotecnología Ambiental, Departamento de Bioprocesos , Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional , Mexico City 07340 , Mexico
| | - Alberto Ordaz
- b Escuela de Ingeniería y Ciencias , Instituto Tecnológico y de Estudios Superiores de Monterrey, Campus Estado de México, Carretera Lago de Guadalupe Km 3.5, Margarita Maza de Juárez, Atizapán de Zaragoza , Estado de México , Mexico
| | - Janet Jan-Roblero
- c Departamento de Microbiología, Escuela Nacional de Ciencias Biológicas , Instituto Politécnico Nacional, Prol. de Carpio y Plan de Ayala s/n, Col. Santo Tomás , Mexico City , Mexico
| | - Fernando Bastida González
- d Laboratorio de Biología Molecular, Laboratorio Estatal de Salud Pública del Estado de México. Paseo Tollocan s/n, Col. La Moderna de la Cruz , Estado de México , Toluca , Mexico
| | - Paola B Zárate Segura
- e Laboratorio de Medicina Traslacional , Escuela Superior de Medicina. Instituto Politécnico Nacional. Plan de San Luis y Díaz Mirón s/n, Col. Santo Tomas , Mexico City , Mexico
| | - Claudia Guerrero-Barajas
- a Laboratorio de Biotecnología Ambiental, Departamento de Bioprocesos , Unidad Profesional Interdisciplinaria de Biotecnología, Instituto Politécnico Nacional , Mexico City 07340 , Mexico
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Wei S, Guo Y. Comparative study of reactor performance and microbial community in psychrophilic and mesophilic biogas digesters under solid state condition. J Biosci Bioeng 2018; 125:543-551. [PMID: 29305269 DOI: 10.1016/j.jbiosc.2017.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2017] [Revised: 11/27/2017] [Accepted: 12/03/2017] [Indexed: 10/18/2022]
Abstract
Psychrophilic (15°C) and mesophilic (35°C) reactor performance and microbial community dynamics were compared when the biogas fermenters were performed at high altitude and solid state condition using animal manure and highland barley straw as substrate. Longer biogas fermentation time, higher peak methane content and lower volatile fatty acids (VFA) accumulation were found at psychrophilic condition compared to that of at mesophilic condition although the biogas production in both temperature conditions was similar. The cumulative biogas production at 35°C and 15°C were 246 (±5) and 225 (±7) ml/g volatile solids, respectively. The highest total VFA concentration under 35°C was 10,796 (±310) mg/kg total solid, while it only reached to 2346 (±87) mg/kg total solid at the condition of 15°C. Additionally, the variation of pH, soluble chemical oxygen demand and total ammonia nitrogen during the anaerobic digestion under psychrophilic condition were much smaller than that of under mesophilic condition. Polymerase chain reaction and denaturing gradient gel electrophoresis analysis followed by 16S rDNA sequencing showed that bacteria of genera Bacillus and Clostridium and archaea of genera Methanosarcina and Methanosaeta played a pivotal role during the biogas production.
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Affiliation(s)
- Suzhen Wei
- Department of Resource and Environment, Tibet Agricultural and Animal Husbandry College, Tibet, Linzhi 860000, China.
| | - Yanfei Guo
- Department of Resource and Environment, Tibet Agricultural and Animal Husbandry College, Tibet, Linzhi 860000, China
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Xu Z, Ben Y, Chen Z, Jiang A, Shen J, Han X. Application and microbial ecology of psychrotrophs in domestic wastewater treatment at low temperature. CHEMOSPHERE 2018; 191:946-953. [PMID: 29145139 DOI: 10.1016/j.chemosphere.2017.10.121] [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: 12/26/2016] [Revised: 10/11/2017] [Accepted: 10/23/2017] [Indexed: 06/07/2023]
Abstract
The feasibility of a bunch of screened psychrotrophs being applied to low-temperature wastewater treatment was investigated. The screened psychrophillic strains are capable of growth at a broad temperature-range from 0 to 40 °C and exhibit a preferable TTC-dehydrogenase activity at low temperature (4-10 °C). Along the sharply fluctuant temperatures (25-4-25 °C), the screened psychrotrophs (compared with the indigenous mesophiles) demonstrate less fluctuations of COD removal and more rapid recovery after temperature shocks. COD removal of approximate 80% was recorded by single psychrotrophs (while only 10% by single mesophiles) at low temperature (4 °C). Soft polyurethane foam showed better performance for psychrotrophs immobilization, with the optimal filling rate of 30% (v/v) in the bioreactor. The observation shows that the immobilized psychrotrophs demonstrated a relatively high performance on both conventional and emerging organic contaminants removals at low temperature. In order to check the feasibility of the screened psychrotrophs in treating actual domestic wastewater, a pilot-scale ICABR bioreactor was operated firstly at low temperature (4 °C) and then at seasonal varying temperatures (0-30 °C) for one year, the influent COD of 150-600 mg L-1 was efficiently reduced to 40 ± 18 mg L-1 under the conditions of an overall hydraulic retention time of 10 h. Furthermore, psychrotrophs performed stably as the predominant bacteria family during the whole operation. This study provides evidence that microbial intensification with psychrotrophs was a feasible strategy to improve the efficiency of conventional wastewater treatment process at low temperature.
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Affiliation(s)
- Zhenzhen Xu
- College of Geography and Environment, Shandong Normal University, Jinan 250014, PR China.
| | - Yue Ben
- Water Works Department, State Nuclear Electric Power Planning Design and Research Institute Co. LTD, Beijing 100095, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Zhonglin Chen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Anxi Jiang
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jimin Shen
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Xiaoyun Han
- State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
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10
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Khan MD, Khan N, Nizami AS, Rehan M, Sabir S, Khan MZ. Effect of co-substrates on biogas production and anaerobic decomposition of pentachlorophenol. BIORESOURCE TECHNOLOGY 2017; 238:492-501. [PMID: 28475991 DOI: 10.1016/j.biortech.2017.04.063] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/06/2017] [Revised: 04/16/2017] [Accepted: 04/17/2017] [Indexed: 06/07/2023]
Abstract
This study aims to examine the effect of different co-substrates on the anaerobic degradation of pentachlorophenol (PCP) with simultaneous production of biogas. Acetate and glucose were added as co-substrates to monitor and compare the methanogenic reaction during PCP degradation. During the experiment, a chemical oxygen demand (COD) removal efficiency of 80% was achieved. Methane (CH4) production was higher in glucose-fed anaerobic reactors with the highest amount of CH4 (303.3µL) produced at 200ppm of PCP. Scanning electron microscopy (SEM) demonstrates the high porous structure of anaerobic sludge with uniform channels confirming better mass transfer and high PCP removal. Quantitative real-time PCR (qPCR) revealed that methanogens were the dominating species while some sulfate reducing bacteria (SRBs) were also found in the reactors. The study shows that strategic operation of the anaerobic reactor can be a feasible option for efficient degradation of complex substrates like PCP along with the production of biogas.
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Affiliation(s)
- Mohammad Danish Khan
- Environmental Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Nishat Khan
- Environmental Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Abdul-Sattar Nizami
- Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, Saudi Arabia
| | - Mohammad Rehan
- Center of Excellence in Environmental Studies (CEES), King Abdulaziz University, Jeddah, Saudi Arabia
| | - Suhail Sabir
- Environmental Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India
| | - Mohammad Zain Khan
- Environmental Research Laboratory, Department of Chemistry, Aligarh Muslim University, Aligarh 202002, Uttar Pradesh, India.
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11
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Seib MD, Berg KJ, Zitomer DH. Influent wastewater microbiota and temperature influence anaerobic membrane bioreactor microbial community. BIORESOURCE TECHNOLOGY 2016; 216:446-452. [PMID: 27262719 DOI: 10.1016/j.biortech.2016.05.098] [Citation(s) in RCA: 36] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/23/2016] [Revised: 05/20/2016] [Accepted: 05/24/2016] [Indexed: 06/05/2023]
Abstract
Sustainable municipal wastewater recovery scenarios highlight benefits of anaerobic membrane bioreactors (AnMBRs). However, influences of continuous seeding by influent wastewater and temperature on attached-growth AnMBRs are not well understood. In this study, four bench-scale AnMBR operated at 10 and 25°C were fed synthetic (SPE) and then real (PE) primary effluent municipal wastewater. Illumina sequencing revealed different bacterial communities in each AnMBR in response to temperature and bioreactor configuration, whereas differences were not observed in archaeal communities. Activity assays revealed hydrogenotrophic methanogenesis was the dominant methanogenic pathway at 10°C. The significant relative abundance of Methanosaeta at 10°C concomitant with low acetoclastic methanogenic activity may indicate possible Methanosaeta-Geobacter direct interspecies electron transfer. When AnMBR feed was changed to PE, continual seeding with wastewater microbiota caused AnMBR microbial communities to shift, becoming more similar to PE microbiota. Therefore, influent wastewater microbiota, temperature and reactor configuration influenced the AnMBR microbial community.
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Affiliation(s)
- M D Seib
- Department of Civil, Construction and Environmental Engineering, Marquette University, P.O. Box 1881, Milwaukee, WI 53233, USA.
| | - K J Berg
- Department of Civil, Construction and Environmental Engineering, Marquette University, P.O. Box 1881, Milwaukee, WI 53233, USA
| | - D H Zitomer
- Department of Civil, Construction and Environmental Engineering, Marquette University, P.O. Box 1881, Milwaukee, WI 53233, USA
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12
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Guo J, Fu X, Andrés Baquero G, Sobhani R, Nolasco DA, Rosso D. Trade-off between carbon emission and effluent quality of activated sludge processes under seasonal variations of wastewater temperature and mean cell retention time. THE SCIENCE OF THE TOTAL ENVIRONMENT 2016; 547:331-344. [PMID: 26789371 DOI: 10.1016/j.scitotenv.2015.12.102] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/28/2015] [Revised: 12/07/2015] [Accepted: 12/21/2015] [Indexed: 06/05/2023]
Abstract
Over the seasonal cycles, the mean cell retention time (MCRT) of the activated sludge process is varied to compensate the wastewater temperature variations. The effects of these variations on the carbon footprint (CFP) and effluent quality index (EQI) of a conventional activated sludge (CAS) process and a nitrification/denitrification (NDN) process were quantified. The carbon emission included both biogenic and non-biogenic carbon. Carbon emissions of wasted biosolids management were also addressed. Our results confirmed that the effluent quality indicated by EQI was not necessarily improved by increasing MCRT. Higher MCRT increased the carbon emission and reduced excess sludge production, which decreased the potential for biogas energy recovery. The NDN process was preferable to the CAS process from the perspective of effluent quality. This consideration extended to the whole plant CFP if the N2O emitted during NDN was limited ([N2O]<1% [NH4(+)]removed) as the carbon emission per unit effluent quality achieved by NDN process is less than that of the CAS process. By putting forward carbon emission intensity (γ) derived from CFP and EQI, our work provides a quantitative tool for decision makers evaluating process alternatives when there is a trade-off between carbon emission and effluent quality.
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Affiliation(s)
- Jingbo Guo
- School of Civil and Architecture Engineering, Northeast Dianli University, Jilin 132012, PR China.
| | - Xin Fu
- School of Civil and Architecture Engineering, Northeast Dianli University, Jilin 132012, PR China
| | - G Andrés Baquero
- Ciencia e Ingeniería del Agua y el Ambiente, Pontificia Universidad Javeriana, Carrera 7 No. 40-62, Bogotá D.C., Colombia
| | - Reza Sobhani
- Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA
| | - Daniel A Nolasco
- Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA; Nolasco y Asociados, S.A., Congreso 1908, Piso 2D, Buenos Aires C1428BVB, Argentina
| | - Diego Rosso
- Water-Energy Nexus Center, University of California, Irvine, CA 92697-2175, USA; Department of Civil and Environmental Engineering, University of California, Irvine, CA 92697-2175, USA
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13
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Chen S, He Q. Distinctive non-methanogen archaeal populations in anaerobic digestion. Appl Microbiol Biotechnol 2015; 100:419-30. [PMID: 26373725 DOI: 10.1007/s00253-015-6951-0] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2015] [Revised: 08/13/2015] [Accepted: 08/22/2015] [Indexed: 11/24/2022]
Abstract
Methanogens define the archaeal communities involved in anaerobic digestion. Recently, non-methanogen archaeal populations have been unexpectedly identified in anaerobic digestion processes. To gain insight into the ecophysiology of these uncharacterized archaeal populations, for the first time, a phylogenetic analysis was performed on a collection of non-methanogen archaeal 16S rRNA gene sequences from anaerobic digesters of broad geographic distribution, revealing a distinct clade formed by these sequences in subgroup 6 of the Miscellaneous Crenarchaeotal Group in the newly proposed archaeal phylum Bathyarchaeota. This exclusive phylogenetic assemblage enabled the development of a real-time quantitative PCR (qPCR) assay specifically targeting these non-methanogen archaeal populations in anaerobic digestion. Application of the qPCR assay in continuous anaerobic digesters indicated that these archaeal populations were minor constituents of the archaeal communities, and the abundance of these populations remained relatively constant irrespective of process perturbations. Analysis of the archaeal populations in methanogenic communities further revealed the co-occurrence of these non-methanogen archaea with acetoclastic methanogens. Nevertheless, the low abundance of non-methanogen archaea as compared with acetoclastic methanogens suggests that the non-methanogen archaeal populations were not major players in animal waste-fed methanogenic processes investigated in this study and the functions of these archaeal populations remain to be identified.
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Affiliation(s)
- Si Chen
- Department of Civil and Environmental Engineering, The University of Tennessee, Knoxville, TN, 37996, USA
| | - Qiang He
- Department of Civil and Environmental Engineering, The University of Tennessee, Knoxville, TN, 37996, USA. .,Institute for a Secure and Sustainable Environment, The University of Tennessee, Knoxville, TN, 37996, USA.
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14
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Zhang Y, Hu M, Li P, Wang X, Meng Q. Analysis of trichloroethylene removal and bacterial community function based on pH-adjusted in an upflow anaerobic sludge blanket reactor. Appl Microbiol Biotechnol 2015; 99:9289-97. [PMID: 26189017 DOI: 10.1007/s00253-015-6800-1] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2015] [Accepted: 06/24/2015] [Indexed: 10/23/2022]
Abstract
The study reported the upflow anaerobic sludge blanket (UASB) reactor performance in treating wastewater containing trichloroethylene (TCE) and characterized variations of bacteria composition and structure by changing the pH from 6.0 to 8.0. A slightly acidic environment (pH < 7.0) had a greater impact on the TCE removal. Illumina pyrosequencing was applied to investigate the bacterial community changes in response to pH shifts. The results demonstrated that pH greatly influenced the dominance and presence of specific populations. The potential TCE degradation pathway in the UASB reactor was proposed. Importantly, the genus Dehalobacter which was capable of reductively dechlorinating TCE was detected, and it was not found at pH of 6.0, which presumably is the reason why the removal efficiency of TCE was the lowest (80.73 %). Through Pearson correlation analyses, the relative abundance of Dehalobacter positively correlated with TCE removal efficiency (R = 0.912). However, the relative abundance of Lactococcus negatively correlated with TCE removal efficiency according to the results from Pearson correlation analyses and redundancy analysis (RDA).
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Affiliation(s)
- Ying Zhang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China.
| | - Miao Hu
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Pengfei Li
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Xin Wang
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
| | - Qingjuan Meng
- School of Resources and Environment, Northeast Agricultural University, Harbin, 150030, People's Republic of China
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15
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Su C, Li W, Wang K, Li Y. Start-up procedures and analyses of sludge characteristics in a novel double circle anaerobic reactor for treating traditional Chinese medicine wastewater. ENVIRONMENTAL TECHNOLOGY 2015; 36:1529-1537. [PMID: 25484233 DOI: 10.1080/09593330.2014.995141] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/04/2023]
Abstract
The start-up procedures and characteristics of the granular sludge from a novel double circle (DC) anaerobic reactor for treating traditional Chinese medicine (TCM) wastewater were investigated. Following a start-up period, the DC reactor demonstrated good chemical oxygen demand removal at 96.87%. The Fourier transform infrared spectra and excitation-emission matrix (EEM) fluorescence spectra from the soluble microbial products of the effluent showed that amino acid and aromatic compounds in TCM wastewater were effectively removed by the DC reactor. The peak of the particle size distribution from the granular sludge in the first reaction area of the DC reactor ranged from 700 to 1500 µm with a mean size of 513 µm, and the mean size of the granular sludge in the second reaction area was approximately 250 µm. The protein-like peak in the EEM fluorescence clearly decreased and the coenzyme F420 of the fluorescence peak clearly increased for the extracellular polymeric substances of the granular sludge.
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Affiliation(s)
- Chengyuan Su
- a School of Municipal and Environmental Engineering , Harbin Institute of Technology , 73 Huanghe Road, Harbin 150090 , People Republic of China
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16
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Gunnigle E, Siggins A, Botting CH, Fuszard M, O'Flaherty V, Abram F. Low-temperature anaerobic digestion is associated with differential methanogenic protein expression. FEMS Microbiol Lett 2015; 362:fnv059. [PMID: 25862577 DOI: 10.1093/femsle/fnv059] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 04/07/2015] [Indexed: 11/14/2022] Open
Abstract
Anaerobic digestion (AD) is an attractive wastewater treatment technology, leading to the generation of recoverable biofuel (methane). Most industrial AD applications, carry excessive heating costs, however, as AD reactors are commonly operated at mesophilic temperatures while handling waste streams discharged at ambient or cold temperatures. Consequently, low-temperature AD represents a cost-effective strategy for wastewater treatment. The comparative investigation of key microbial groups underpinning laboratory-scale AD bioreactors operated at 37, 15 and 7°C was carried out. Community structure was monitored using 16S rRNA clone libraries, while abundance of the most prominent methanogens was investigated using qPCR. In addition, metaproteomics was employed to access the microbial functions carried out in situ. While δ-Proteobacteria were prevalent at 37°C, their abundance decreased dramatically at lower temperatures with inverse trends observed for Bacteroidetes and Firmicutes. Methanobacteriales and Methanosaeta were predominant at all temperatures investigated while Methanomicrobiales abundance increased at 15°C compared to 37 and 7°C. Changes in operating temperature resulted in the differential expression of proteins involved in methanogenesis, which was found to occur in all bioreactors, as corroborated by bioreactors' performance. This study demonstrated the value of employing a polyphasic approach to address microbial community dynamics and highlighted the functional redundancy of AD microbiomes.
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Affiliation(s)
- Eoin Gunnigle
- Microbial Ecology Laboratory, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland Functional Environmental Microbiology, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Alma Siggins
- Microbial Ecology Laboratory, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Catherine H Botting
- BSRC Mass Spectrometry and Proteomics Facility, Biomedical Sciences Research Complex, North Haugh, University of St Andrews, Fife KY16 9ST, Scotland
| | - Matthew Fuszard
- BSRC Mass Spectrometry and Proteomics Facility, Biomedical Sciences Research Complex, North Haugh, University of St Andrews, Fife KY16 9ST, Scotland
| | - Vincent O'Flaherty
- Microbial Ecology Laboratory, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
| | - Florence Abram
- Functional Environmental Microbiology, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
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17
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Impact of membrane addition for effluent extraction on the performance and sludge characteristics of upflow anaerobic sludge blanket reactors treating municipal wastewater. J Memb Sci 2015. [DOI: 10.1016/j.memsci.2014.12.021] [Citation(s) in RCA: 47] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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18
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Zhang Y, Hu M, Li P, Wang X, Meng Q. Trichloroethylene removal and bacterial variations in the up-flow anaerobic sludge blanket reactor in response to temperature shifts. Appl Microbiol Biotechnol 2015; 99:6091-102. [DOI: 10.1007/s00253-015-6480-x] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2015] [Revised: 02/07/2015] [Accepted: 02/12/2015] [Indexed: 12/26/2022]
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19
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Zhang Y, Wang X, Hu M, Li P. Effect of hydraulic retention time (HRT) on the biodegradation of trichloroethylene wastewater and anaerobic bacterial community in the UASB reactor. Appl Microbiol Biotechnol 2014; 99:1977-87. [PMID: 25277413 DOI: 10.1007/s00253-014-6096-6] [Citation(s) in RCA: 65] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2014] [Revised: 09/11/2014] [Accepted: 09/12/2014] [Indexed: 10/24/2022]
Abstract
This study utilizes the unique merits of an 8-L laboratory upflow anaerobic sludge blanket (UASB) reactor for treating synthetic wastewater containing trichloroethylene (TCE). The reactor was operated at different hydraulic retention times (HRT) of 25, 20, 15, 10, and 5 h. TCE removal efficiency decreased from 99 to 85 % when the HRT was lowered down from 25 to 5 h, as well as chemical oxygen demand (COD) removal efficiency (from 95 to 84.15 %). Using Illumina 16S rRNA gene MiSeq sequencing, we investigated the evolution of bacterial communities in the anaerobic sludge under five different conditions of HRT. In total, 106,387 effective sequences of the 16S rRNA gene were generated from 5 samples that widely represented the diversity of microbial community. Sequence analysis consisting of several novel taxonomic levels ranging from phyla to genera revealed the percentages of these bacterial groups in each sample under different HRTs. The differences found among the five samples indicated that HRT had effects on the structures of bacterial communities and the changes of bacterial communities associated with the effect of HRT on the performance of the reactor. Sequence analyses showed that Bacteroidetes and Firmicutes were the dominant phyla. It is notable that the class Dehalococcoidia was found in the samples at HRT of 5, 10, 20, and 25 h, respectively, in which there were some dechlorination strains. Moreover, a tremendous rise of TCE removal efficiency from HRT of 5 h to HRT of 10 h was found.
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Affiliation(s)
- Ying Zhang
- School of Resource and Environment, Northeast Agricultural University, Harbin, 150030, China,
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20
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Bialek K, Cysneiros D, O’Flaherty V. Hydrolysis, acidification and methanogenesis during low-temperature anaerobic digestion of dilute dairy wastewater in an inverted fluidised bioreactor. Appl Microbiol Biotechnol 2014; 98:8737-50. [DOI: 10.1007/s00253-014-5864-7] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2014] [Revised: 05/23/2014] [Accepted: 05/23/2014] [Indexed: 11/28/2022]
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21
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Mu Y, Yang HY, Wang YZ, He CS, Zhao QB, Wang Y, Yu HQ. The maximum specific hydrogen-producing activity of anaerobic mixed cultures: definition and determination. Sci Rep 2014; 4:5239. [PMID: 24912488 PMCID: PMC4050381 DOI: 10.1038/srep05239] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2014] [Accepted: 05/21/2014] [Indexed: 11/29/2022] Open
Abstract
Fermentative hydrogen production from wastes has many advantages compared to various chemical methods. Methodology for characterizing the hydrogen-producing activity of anaerobic mixed cultures is essential for monitoring reactor operation in fermentative hydrogen production, however there is lack of such kind of standardized methodologies. In the present study, a new index, i.e., the maximum specific hydrogen-producing activity (SHAm) of anaerobic mixed cultures, was proposed, and consequently a reliable and simple method, named SHAm test, was developed to determine it. Furthermore, the influences of various parameters on the SHAm value determination of anaerobic mixed cultures were evaluated. Additionally, this SHAm assay was tested for different types of substrates and bacterial inocula. Our results demonstrate that this novel SHAm assay was a rapid, accurate and simple methodology for determining the hydrogen-producing activity of anaerobic mixed cultures. Thus, application of this approach is beneficial to establishing a stable anaerobic hydrogen-producing system.
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Affiliation(s)
- Yang Mu
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Hou-Yun Yang
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Ya-Zhou Wang
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Chuan-Shu He
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Quan-Bao Zhao
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Yi Wang
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
| | - Han-Qing Yu
- Department of Chemistry, University of Science & Technology of China, Hefei, 230026, China
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22
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Li W, Su C, Liu X, Zhang L. Influence of the organic loading rate on the performance and the granular sludge characteristics of an EGSB reactor used for treating traditional Chinese medicine wastewater. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2014; 21:8167-8175. [PMID: 24677060 DOI: 10.1007/s11356-014-2709-y] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/14/2013] [Accepted: 02/27/2014] [Indexed: 06/03/2023]
Abstract
The effects of the organic loading rate (OLR) on the performance and the granular sludge characteristics of an expanded granular sludge bed (EGSB) reactor used for treating real traditional Chinese medicine (TCM) wastewater were investigated. Over 90% of the COD removal by the EGSB reactor was observed at the OLRs of 4 to 13 kg COD/(m(3) day). However, increasing the OLR to 20 kg COD/(m(3) day) by reducing the hydraulic retention time (HRT 6 h) reduced the COD removal efficiency to 78%. The volatile fatty acid (VFA) concentration was 512.22 mg/L, resulting in an accumulation of VFAs, and propionic acid was the main acidification product, accounting for 66.51% of the total VFAs. When the OLR increased from 10 to 20 kg COD/(m(3) day), the average size of the granule sludge decreased from 469 to 258 μm. There was an obvious reduction in the concentration of Ca(2+) and Mg(2+) in the granular sludge. The visible humic acid-like peak was identified in the three-dimensional excitation-emission matrix (EEM) fluorescence spectra of the soluble microbial products (SMPs). The fatty acid bond, amide II bond, amide III bond, and C-H bond bending were also observed in the Fourier transform infrared (FTIR) spectra of the SMPs. Methanobacterium formicicum, Methanococcus, and Bacteria populations exhibited significant shifts, and these changes were accompanied by an increase in VFA production. The results indicated that a short HRT and high OLR in the EGSB reactor caused the accumulation of polysaccharides, protein, and VFAs, thereby inhibiting the activity of methanogenic bacteria and causing granular sludge corruption.
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Affiliation(s)
- Weiguang Li
- School of Municipal and Environmental Engineering, Harbin Institute of Technology, 73 Huanghe Road, Harbin, 150090, People's Republic of China,
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23
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A functional approach to uncover the low-temperature adaptation strategies of the archaeon Methanosarcina barkeri. Appl Environ Microbiol 2013; 79:4210-9. [PMID: 23645201 DOI: 10.1128/aem.03787-12] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Low-temperature anaerobic digestion (LTAD) technology is underpinned by a diverse microbial community. The methanogenic archaea represent a key functional group in these consortia, undertaking CO2 reduction as well as acetate and methylated C1 metabolism with subsequent biogas (40 to 60% CH4 and 30 to 50% CO2) formation. However, the cold adaptation strategies, which allow methanogens to function efficiently in LTAD, remain unclear. Here, a pure-culture proteomic approach was employed to study the functional characteristics of Methanosarcina barkeri (optimum growth temperature, 37°C), which has been detected in LTAD bioreactors. Two experimental approaches were undertaken. The first approach aimed to characterize a low-temperature shock response (LTSR) of M. barkeri DSMZ 800(T) grown at 37°C with a temperature drop to 15°C, while the second experimental approach aimed to examine the low-temperature adaptation strategies (LTAS) of the same strain when it was grown at 15°C. The latter experiment employed cell viability and growth measurements (optical density at 600 nm [OD600]), which directly compared M. barkeri cells grown at 15°C with those grown at 37°C. During the LTSR experiment, a total of 127 proteins were detected in 37°C and 15°C samples, with 20 proteins differentially expressed with respect to temperature, while in the LTAS experiment 39% of proteins identified were differentially expressed between phases of growth. Functional categories included methanogenesis, cellular information processing, and chaperones. By applying a polyphasic approach (proteomics and growth studies), insights into the low-temperature adaptation capacity of this mesophilically characterized methanogen were obtained which suggest that the metabolically diverse Methanosarcinaceae could be functionally relevant for LTAD systems.
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Impact of trichloroethylene exposure on the microbial diversity and protein expression in anaerobic granular biomass at 37°C and 15°C. ARCHAEA-AN INTERNATIONAL MICROBIOLOGICAL JOURNAL 2012; 2012:940159. [PMID: 23197942 PMCID: PMC3502766 DOI: 10.1155/2012/940159] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 07/13/2012] [Accepted: 09/14/2012] [Indexed: 11/20/2022]
Abstract
Granular biomass from a laboratory-scale anaerobic bioreactor trial was analysed to identify changes in microbial community structure and function in response to temperature and trichloroethylene (TCE). Two bioreactors were operated at 37°C, while two were operated at 15°C. At the time of sampling, one of each temperature pair of bioreactors was exposed to process failure-inducing concentrations of TCE (60 mg L−1) while the other served as a TCE-free control. Bacterial community structure was investigated using denaturing gradient gel electrophoresis (DGGE) and 16S rRNA gene clone library analysis. Temperature was identified as an important factor for bacterial community composition, while minor differences were associated with trichloroethylene supplementation. Proteobacteria was the dominant phylum in all bioreactors, while clone library analysis revealed a higher proportion of Bacteroidetes-, Chloroflexi-, and Firmicutes-like clones at 15°C than at 37°C. Comparative metaproteomics in the presence and absence of TCE was carried out by two-dimensional gel electrophoresis (2-DGE), and 28 protein spots were identified, with putative functions related to cellular processes, including methanogenesis, glycolysis, the glyoxylate cycle, and the methyl malonyl pathway. A good agreement between metaproteomic species assignment and phylogenetic information was observed, with 10 of the identified proteins associated with members of the phylum Proteobacteria.
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Shukla AK, Upadhyay SN, Dubey SK. Current trends in trichloroethylene biodegradation: a review. Crit Rev Biotechnol 2012; 34:101-14. [PMID: 23057686 DOI: 10.3109/07388551.2012.727080] [Citation(s) in RCA: 35] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/15/2023]
Abstract
Over the past few years biodegradation of trichloroethylene (TCE) using different microorganisms has been investigated by several researchers. In this review article, an attempt has been made to present a critical summary of the recent results related to two major processes--reductive dechlorination and aerobic co-metabolism used for TCE biodegradation. It has been shown that mainly Clostridium sp. DC-1, KYT-1, Dehalobacter, Dehalococcoides, Desulfuromonas, Desulfitobacterium, Propionibacterium sp. HK-1, and Sulfurospirillum bacterial communities are responsible for the reductive dechlorination of TCE. Efficacy of bacterial communities like Nitrosomonas, Pseudomonas, Rhodococcus, and Xanthobacter sp. etc. for TCE biodegradation under aerobic conditions has also been examined. Mixed cultures of diazotrophs and methanotrophs have been used for TCE degradation in batch and continuous cultures (biofilter) under aerobic conditions. In addition, some fungi (Trametes versicolor, Phanerochaete chrysosporium ME-446) and Actinomycetes have also been used for aerobic biodegradation of TCE. The available information on kinetics of biofiltration of TCE and its degradation end-products such as CO2 are discussed along with the available results on the diversity of bacterial community obtained using molecular biological approaches. It has emerged that there is a need to use metabolic engineering and molecular biological tools more intensively to improve the robustness of TCE degrading microbial species and assess their diversity.
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Affiliation(s)
- Awadhesh Kumar Shukla
- Department of Botany, Faculty of Science, Banaras Hindu University , Varanasi , India and
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26
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McKeown RM, Hughes D, Collins G, Mahony T, O’Flaherty V. Low-temperature anaerobic digestion for wastewater treatment. Curr Opin Biotechnol 2012; 23:444-51. [DOI: 10.1016/j.copbio.2011.11.025] [Citation(s) in RCA: 68] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2011] [Revised: 11/18/2011] [Accepted: 11/24/2011] [Indexed: 10/14/2022]
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