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Wang L, Lee E, Barlaz MA, de Los Reyes FL. Linking microbial population dynamics in anaerobic bioreactors to food waste type and decomposition stage. WASTE MANAGEMENT (NEW YORK, N.Y.) 2024; 186:77-85. [PMID: 38865907 DOI: 10.1016/j.wasman.2024.06.004] [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: 02/11/2024] [Revised: 05/18/2024] [Accepted: 06/06/2024] [Indexed: 06/14/2024]
Abstract
A key question in anaerobic microbial ecology is how microbial communities develop over different stages of waste decomposition and whether these changes are specific to waste types. We destructively sampled over time 26 replicate bioreactors cultivated on fruit/vegetable waste (FVW) and meat waste (MW) based on pre-defined waste components and composition. To characterize community shifts, we examined 16S rRNA genes from both the leachate and solid fractions of the waste. Waste decomposition occurred faster in FVW than MW, as accumulation of ammonia in MW reactors led to inhibition of methanogenesis. We identified population succession during different stages of waste decomposition and linked specific populations to different waste types. Community analyses revealed underrepresentation of methanogens in the leachate fractions, emphasizing the importance of consistent and representative sampling when characterizing microbial communities in solid waste.
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Affiliation(s)
- Ling Wang
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695
| | - Eunyoung Lee
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695
| | - Morton A Barlaz
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695
| | - Francis L de Los Reyes
- Department of Civil, Construction, and Environmental Engineering, North Carolina State University, Raleigh, NC 27695.
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2
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Fundneider-Kale S, Kerres J, Engelhart M. Impact of benzalkonium chloride on anaerobic granules and its long-term effects on reactor performance. JOURNAL OF HAZARDOUS MATERIALS 2024; 476:135183. [PMID: 39024763 DOI: 10.1016/j.jhazmat.2024.135183] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/10/2024] [Revised: 07/06/2024] [Accepted: 07/10/2024] [Indexed: 07/20/2024]
Abstract
This study assessed the inhibitory and performance-degrading effects induced by the cationic surfactant benzalkonium chloride (BAC) on anaerobic granules during the long-term operation of a laboratory-scale expanded granular sludge bed (EGSB) reactor. To address the critical scientific problem of how BAC affects the efficiency of EGSB reactors, this research uniquely evaluated the long-term stress response to BAC by systematically comparing continuous and discontinuous inhibitor exposure scenarios. The novel comparison demonstrated that inhibitor concentration is of minor relevance compared to the biomass-specific cumulative inhibitor load in the reactor. After exceeding a critical biomass-specific cumulative inhibitor load of 6.1-6.5 mg BAC/g VS, continuous and discontinuous exposure to BAC caused comparable significant deterioration in reactor performance, including accumulation of volatile fatty acids (VFA), decreased removal efficiency, reduced methane production, as well as the wash-out, flotation, and disintegration of anaerobic granules. BAC exposures had a more detrimental effect on methanogenesis than on acidogenesis. Moreover, long-term stress by BAC led to an inhibition of protein production, resulting in a decreased protein-to-polysaccharide ratio of extracellular polymeric substances (EPS) that promoted destabilizing effects on the granules. Finally, hydrogenotrophic methanogenesis was triggered. Reactor performance could not be restored due to the severe loss of granular sludge.
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Affiliation(s)
- S Fundneider-Kale
- Technical University of Darmstadt, Institute IWAR, Chair of Wastewater Technology, Franziska-Braun-Straße 7, D-64287 Darmstadt, Germany.
| | - J Kerres
- Technical University of Darmstadt, Institute IWAR, Chair of Wastewater Technology, Franziska-Braun-Straße 7, D-64287 Darmstadt, Germany
| | - M Engelhart
- Technical University of Darmstadt, Institute IWAR, Chair of Wastewater Technology, Franziska-Braun-Straße 7, D-64287 Darmstadt, Germany
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3
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Ali A, Vishnivetskaya TA, Chauhan A. Comparative analysis of prokaryotic microbiomes in high-altitude active layer soils: insights from Ladakh and global analogues using In-Silico approaches. Braz J Microbiol 2024:10.1007/s42770-024-01365-3. [PMID: 38758507 DOI: 10.1007/s42770-024-01365-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2023] [Accepted: 04/08/2024] [Indexed: 05/18/2024] Open
Abstract
The active layer is the portion of soil overlaying the permafrost that freezes and thaws seasonally. It is a harsh habitat in which a varied and vigorous microbial population thrives. The high-altitude active layer soil in northern India is a unique and important cryo-ecosystem. However, its microbiology remains largely unexplored. It represents a unique reservoir for microbial communities with adaptability to harsh environmental conditions. In the Changthang region of Ladakh, the Tsokar area is a high-altitude permafrost-affected area situated in the southern part of Ladakh, at a height of 4530 m above sea level. Results of the comparison study with the QTP, Himalayan, Alaskan, Russian, Canadian and Polar active layers showed that the alpha diversity was significantly higher in the Ladakh and QTP active layers as the environmental condition of both the sites were similar. Moreover, the sampling site in the Ladakh region was in a thawing condition at the time of sampling which possibly provided nutrients and access to alternative nitrogen and carbon sources to the microorganisms thriving in it. Analysis of the samples suggested that the geochemical parameters and environmental conditions shape the microbial alpha diversity and community composition. Further analysis revealed that the cold-adapted methanogens were present in the Ladakh, Himalayan, Polar and Alaskan samples and absent in QTP, Russian and Canadian active layer samples. These methanogens could produce methane at slow rates in the active layer soils that could increase the atmospheric temperature owing to climate change.
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Affiliation(s)
- Ahmad Ali
- Department of Zoology, Panjab University, Sector 14, 160014, Chandigarh, India
| | | | - Archana Chauhan
- Department of Zoology, Panjab University, Sector 14, 160014, Chandigarh, India.
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4
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Conrad R. Complexity of temperature dependence in methanogenic microbial environments. Front Microbiol 2023; 14:1232946. [PMID: 37485527 PMCID: PMC10359720 DOI: 10.3389/fmicb.2023.1232946] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/01/2023] [Accepted: 06/20/2023] [Indexed: 07/25/2023] Open
Abstract
There is virtually no environmental process that is not dependent on temperature. This includes the microbial processes that result in the production of CH4, an important greenhouse gas. Microbial CH4 production is the result of a combination of many different microorganisms and microbial processes, which together achieve the mineralization of organic matter to CO2 and CH4. Temperature dependence applies to each individual step and each individual microbe. This review will discuss the different aspects of temperature dependence including temperature affecting the kinetics and thermodynamics of the various microbial processes, affecting the pathways of organic matter degradation and CH4 production, and affecting the composition of the microbial communities involved. For example, it was found that increasing temperature results in a change of the methanogenic pathway with increasing contribution from mainly acetate to mainly H2/CO2 as immediate CH4 precursor, and with replacement of aceticlastic methanogenic archaea by thermophilic syntrophic acetate-oxidizing bacteria plus thermophilic hydrogenotrophic methanogenic archaea. This shift is consistent with reaction energetics, but it is not obligatory, since high temperature environments exist in which acetate is consumed by thermophilic aceticlastic archaea. Many studies have shown that CH4 production rates increase with temperature displaying a temperature optimum and a characteristic apparent activation energy (Ea). Interestingly, CH4 release from defined microbial cultures, from environmental samples and from wetland field sites all show similar Ea values around 100 kJ mol-1 indicating that CH4 production rates are limited by the methanogenic archaea rather than by hydrolysis of organic matter. Hence, the final rather than the initial step controls the methanogenic degradation of organic matter, which apparently is rarely in steady state.
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Mozhiarasi V, Natarajan TS, Dhamodharan K. A high-value biohythane production: Feedstocks, reactor configurations, pathways, challenges, technoeconomics and applications. ENVIRONMENTAL RESEARCH 2023; 219:115094. [PMID: 36535394 DOI: 10.1016/j.envres.2022.115094] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/07/2022] [Revised: 12/13/2022] [Accepted: 12/15/2022] [Indexed: 06/17/2023]
Abstract
In recent years, the demand for high-quality biofuels from renewable sources has become an aspirational goal to offer a clean environment by alternating the depleting fossil fuels to meet future energy needs. In this aspect, biohythane production from wastes has received extensive research interest since it contains superior fuel characteristics than the promising conventional biofuel i.e. biogas. The main aim is to promote research and potentials of biohythane production by a systematic review of scientific literature on the biohythane production pathways, substrate/microbial consortium suitability, reactor design, and influential process/operational factors. Reactor configuration also decides the product yield in addition to other key factors like waste composition, temperature, pH, retention time and loading rates. Hence, a detailed emphasis on different reactor configurations with respect to the type of feedstock has also been given. The technical challenges are highlighted towards process optimization and system scale up. Meanwhile, solutions to improve product yield, technoeconomics, applications and key policy and governance factors to build a hydrogen based society have also been discussed.
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Affiliation(s)
- Velusamy Mozhiarasi
- CLRI Regional Centre, CSIR-Central Leather Research Institute (CSIR-CLRI), Jalandhar, 144 021, Punjab, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India.
| | - Thillai Sivakumar Natarajan
- Environmental Science Laboratory, CSIR-Central Leather Research Institute (CSIR-CLRI), Chennai, 600 020, Tamil Nadu, India; Academy of Scientific and Innovative Research (AcSIR), Ghaziabad, Uttar Pradesh, India
| | - Kondusamy Dhamodharan
- School of Energy and Environment, Thapar Institute of Engineering and Technology, Patiala, 147 004, Punjab, India
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6
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Zhong Y, He J, Zhang P, Zou X, Pan X, Zhang J. Novel nitrogen-doped biochar supported magnetite promotes anaerobic digestion: Material characterization and metagenomic analysis. BIORESOURCE TECHNOLOGY 2023; 369:128492. [PMID: 36526119 DOI: 10.1016/j.biortech.2022.128492] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Revised: 12/09/2022] [Accepted: 12/12/2022] [Indexed: 06/17/2023]
Abstract
Although different conductive materials have been applied to anaerobic digestion, there has not been a material that can really combine their merits and make up their shortcoming from each other. In this study, a novel nitrogen-doped biochar supported magnetite (Fe3O4@N-BC) was synthesized. Various material characterizations confirmed that nitrogen atoms were successful doped into the biochar and magnetite precipitated on its surface. 5 g/L Fe3O4@N-BC achieved the highest promotion of cumulative CH4 production by 1.75 times compared with the blank group. Further metagenomic analysis revealed that Fe3O4@N-BC could increase the gene abundances of pilA, MmcA, Fpo, Rnf and HdrEd in bacteria Clotridium, Pseudomonas and Syntrophomonas and archaea Methanosarcina. Redundancy analysis showed that it was electrical conductivity and electron exchange capacity that were the key physicochemical characteristics for Fe3O4@N-BC to facilitating direct interspecies electron transfer. This study provides a reference for future conductive material synthesis and its application for anaerobic digestion.
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Affiliation(s)
- Yijie Zhong
- School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China.
| | - Junguo He
- School of Civil Engineering, Guangzhou University, Guangzhou 510006, PR China
| | - Pengfei Zhang
- School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Xiang Zou
- School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Xinlei Pan
- School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
| | - Jie Zhang
- School of Environment, Harbin Institute of Technology, Harbin 150090, PR China; State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, Harbin 150090, PR China
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7
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Wang Y, Mairinger W, Raj SJ, Yakubu H, Siesel C, Green J, Durry S, Joseph G, Rahman M, Amin N, Hassan MZ, Wicken J, Dourng D, Larbi E, Adomako LAB, Senayah AK, Doe B, Buamah R, Tetteh-Nortey JNN, Kang G, Karthikeyan A, Roy S, Brown J, Muneme B, Sene SO, Tuffuor B, Mugambe RK, Bateganya NL, Surridge T, Ndashe GM, Ndashe K, Ban R, Schrecongost A, Moe CL. Quantitative assessment of exposure to fecal contamination in urban environment across nine cities in low-income and lower-middle-income countries and a city in the United States. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 763:143007. [PMID: 34718001 DOI: 10.1016/j.scitotenv.2020.143007] [Citation(s) in RCA: 48] [Impact Index Per Article: 24.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2020] [Revised: 10/08/2020] [Accepted: 10/08/2020] [Indexed: 05/23/2023]
Abstract
BACKGROUND During 2014 to 2019, the SaniPath Exposure Assessment Tool, a standardized set of methods to evaluate risk of exposure to fecal contamination in the urban environment through multiple exposure pathways, was deployed in 45 neighborhoods in ten cities, including Accra and Kumasi, Ghana; Vellore, India; Maputo, Mozambique; Siem Reap, Cambodia; Atlanta, United States; Dhaka, Bangladesh; Lusaka, Zambia; Kampala, Uganda; Dakar, Senegal. OBJECTIVE Assess and compare risk of exposure to fecal contamination via multiple pathways in ten cities. METHODS In total, 4053 environmental samples, 4586 household surveys, 128 community surveys, and 124 school surveys were collected. E. coli concentrations were measured in environmental samples as an indicator of fecal contamination magnitude. Bayesian methods were used to estimate the distributions of fecal contamination concentration and contact frequency. Exposure to fecal contamination was estimated by the Monte Carlo method. The contamination levels of ten environmental compartments, frequency of contact with those compartments for adults and children, and estimated exposure to fecal contamination through any of the surveyed environmental pathways were compared across cities and neighborhoods. RESULTS Distribution of fecal contamination in the environment and human contact behavior varied by city. Universally, food pathways were the most common dominant route of exposure to fecal contamination across cities in low-income and lower-middle-income countries. Risks of fecal exposure via water pathways, such as open drains, flood water, and municipal drinking water, were site-specific and often limited to smaller geographic areas (i.e., neighborhoods) instead of larger areas (i.e., cities). CONCLUSIONS Knowledge of the relative contribution to fecal exposure from multiple pathways, and the environmental contamination level and frequency of contact for those "dominant pathways" could provide guidance for Water, Sanitation, and Hygiene (WASH) programming and investments and enable local governments and municipalities to improve intervention strategies to reduce the risk of exposure to fecal contamination.
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Affiliation(s)
- Yuke Wang
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA.
| | - Wolfgang Mairinger
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Suraja J Raj
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Habib Yakubu
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Casey Siesel
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Jamie Green
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - Sarah Durry
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
| | - George Joseph
- Water Global Practice, The World Bank, Washington, DC, USA
| | - Mahbubur Rahman
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | - Nuhu Amin
- Environmental Interventions Unit, Infectious Disease Division, International Centre for Diarrhoeal Disease Research, Bangladesh (icddr,b), Dhaka, Bangladesh
| | | | | | | | - Eugene Larbi
- Training Research and Networking for Development (TREND), Accra, Ghana
| | | | | | - Benjamin Doe
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard Buamah
- Department of Civil Engineering, Kwame Nkrumah University of Science and Technology, Kumasi, Ghana
| | | | - Gagandeep Kang
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Arun Karthikeyan
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Sheela Roy
- Wellcome Research Laboratory, Christian Medical College, Vellore, India
| | - Joe Brown
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, USA
| | - Bacelar Muneme
- Water Supply and Mapping, WE Consult, Maputo, Mozambique
| | - Seydina O Sene
- Initiative Prospective Agricole et Rurale (IPAR), Dakar, Senegal
| | - Benedict Tuffuor
- Training Research and Networking for Development (TREND), Accra, Ghana
| | - Richard K Mugambe
- Department of Disease Control and Environmental Health, Makerere University School of Public Health, Kampala, Uganda
| | - Najib Lukooya Bateganya
- Department of Environment and Public Health, Kampala Capital City Authority, Kampala, Uganda
| | - Trevor Surridge
- Deutsche Gesellschaft für Internationale Zusammenarbeit (GIZ) GmbH, Lusaka, Zambia
| | | | - Kunda Ndashe
- Department of Environmental Health, Faculty of Health Science, Lusaka Apex Medical University, Lusaka, Zambia
| | - Radu Ban
- Bill & Melinda Gates Foundation, Seattle, WA, USA
| | | | - Christine L Moe
- Center for Global Safe Water, Sanitation, and Hygiene, Hubert Department of Global Health, Rollins School of Public Health, Emory University, Atlanta, GA, USA
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Jiang C, McIlroy SJ, Qi R, Petriglieri F, Yashiro E, Kondrotaite Z, Nielsen PH. Identification of microorganisms responsible for foam formation in mesophilic anaerobic digesters treating surplus activated sludge. WATER RESEARCH 2021; 191:116779. [PMID: 33401166 DOI: 10.1016/j.watres.2020.116779] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2020] [Revised: 12/06/2020] [Accepted: 12/20/2020] [Indexed: 06/12/2023]
Abstract
Foaming is a common operational problem in anaerobic digestion (AD) systems, where hydrophobic filamentous microorganisms are usually considered to be the major cause. However, little is known about the identity of foam-stabilising microorganisms in AD systems, and control measures are lacking. This study identified putative foam forming microorganisms in 13 full-scale mesophilic digesters located at 11 wastewater treatment plants in Denmark, using 16S rRNA gene amplicon sequencing with species-level resolution and fluorescence in situ hybridization (FISH) for visualization. A foaming potential aeration test was applied to classify the digester sludges according to their foaming propensity. A high foaming potential for sludges was linked to the abundance of species from the genus Candidatus Microthrix, immigrating with the feed stream (surplus activated sludge), but also to several novel phylotypes potentially growing in the digester. These species were classified to the genera Ca. Brevefilum (Ca. B. fermentans) and Tetrasphaera (midas_s_5), the families ST-12K33 (midas_s_22), and Rikenellaceae (midas_s_141), and the archaeal genus Methanospirillum (midas_s_2576). Application of FISH showed that these potential foam-forming organisms all had a filamentous morphology. Additionally, it was shown that concentrations of ammonium and total nitrogen correlated strongly to the presence of foam-formers. This study provided new insight into the identity of putative foam-forming microorganisms in mesophilic AD systems, allowing for the subsequent surveillance of their abundances and studies of their ecology. Such information will importantly inform the development of control measures for these problematic microorganisms.
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Affiliation(s)
- Chenjing Jiang
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark; Key Laboratory of Engineering Oceanography, Second Institute of Oceanography, SOA, Hangzhou, 310012, China
| | - Simon Jon McIlroy
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark; Centre for Microbiome Research, School of Biomedical Sciences, Queensland University of Technology (QUT), Translational Research Institute, Woolloongabba, Australia
| | - Rong Qi
- State Key Laboratory of Environmental Aquatic Chemistry, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing, 10085, China
| | - Francesca Petriglieri
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Erika Yashiro
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Zivile Kondrotaite
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark
| | - Per Halkjær Nielsen
- Center for Microbial Communities, Department of Chemistry and Bioscience, Aalborg University, 9220 Aalborg, Denmark.
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9
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Cai Y, Zheng Z, Wang X. Obstacles faced by methanogenic archaea originating from substrate-driven toxicants in anaerobic digestion. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123938. [PMID: 33264986 DOI: 10.1016/j.jhazmat.2020.123938] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/05/2020] [Revised: 09/01/2020] [Accepted: 09/02/2020] [Indexed: 06/12/2023]
Abstract
Anaerobic digestion (AD) is used to treat waste and produce bioenergy. However, toxicants, which originate from the substrate, can inhibit or damage the digestion process. Methanogenic archaea (MA), which are the executor in the methanogenesis stage, are more sensitive than bacteria to these toxicants. This review discusses the effects of substrate-driven toxicants, namely, antibiotics, H2S and sulfate, heavy metals (HMs), long-chain fatty acids (LCFAs), and ammonia nitrogen, on the activity of MAs, methanogenic pathways, and the inter-genus succession of MAs. The adverse effects of these five toxicants on MA include effects on pH, damages to cell membranes, the prevention of protein synthesis, changes in hydrogen partial pressure, a reduction in the bioavailability of trace elements, and hindrance of mass transfer. These effects cause a reduction in MA activity and the succession of MAs and methanogenic pathways, which affect AD performance. Under the stress of these toxicants, succession occurs among HA (hydrogenotrophic methanogen), AA (acetoclastic methanogen), and MM (methylotrophic methanogen), especially HA gradually replaces AA as the dominant MA. Simultaneously, the dominant methanogenic pathway also changes from the aceticlastic pathway to other methanogenic pathways. A comprehensive understanding of the impact of toxicants on MA permits more specific targeting when developing strategies to mitigate or eliminate the effects of these toxicants.
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Affiliation(s)
- Yafan Cai
- College of Agronomy and Biotechnology/Biomass Engineering Center, China Agricultural University, Beijing 100193, China; Department of Biochemical conversion, Deutsches Biomassforschungszentrum gemeinnütziges GmbH, Torgauer Straße116, 04347 Leipzig, Germany
| | - Zehui Zheng
- College of Agronomy and Biotechnology/Biomass Engineering Center, China Agricultural University, Beijing 100193, China
| | - Xiaofen Wang
- College of Agronomy and Biotechnology/Biomass Engineering Center, China Agricultural University, Beijing 100193, China.
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Cabezas A, Bovio P, Etchebehere C. Commercial formulation amendment transiently affects the microbial composition but not the biogas production of a full scale methanogenic UASB reactor. ENVIRONMENTAL TECHNOLOGY 2020; 41:3119-3133. [PMID: 30919752 DOI: 10.1080/09593330.2019.1600042] [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: 11/01/2018] [Accepted: 03/18/2019] [Indexed: 06/09/2023]
Abstract
The treatment of dairy wastewater in methanogenic reactors cause several problems due to their high lipid content. One strategy to overcome these problems is the use of commercial formulations. Here we studied the effect of adding a commercial formulation, designed to improve fat degradation, on both the microbial community composition and reactor performance. Samples from two full-scale Up-flow Anaerobic Sludge Blanket (UASB) reactors in parallel arrangement were analysed. The commercial product was added to one of the reactors while the other was used as control. The amendment increased significantly the fat removal but an accumulation of volatile fatty acids was detected. Nevertheless, no significant differences were observed in the total Chemical Oxygen Demand (COD) removal and biogas production between reactors. A significant change in the bacterial community was not detected by 16S rRNA gene Terminal Restriction Fragment Length Polymorphism (T-RFLP) analysis probably due to the limitation of the technique. A strong change in the composition of the phylum Firmicutes was detected with 16S rRNA gene amplicon sequencing; however, it didn't persist during the whole operation period. The relative abundance of minor Operational Taxonomic Units (OTUs) with sequences related to syntrophic bacteria increased with the amendment. Although a better hydrolytic capacity was obtained when adding the commercial product, the overall process did not improve and no increase in biogas production was detected. Alternative strategies could be applied to avoid the accumulation of intermediary products and improve biogas production as intermittent addition of the commercial product or batch operation of reactors.
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Affiliation(s)
- A Cabezas
- Environmental Microbiology and Biotechnology Laboratory, Department of Environmental Sciences, Uruguay Technological University (UTEC), Durazno, Uruguay
| | - P Bovio
- Microbial Ecology Laboratory, Department of Biochemistry and Microbial Genetics, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
| | - C Etchebehere
- Microbial Ecology Laboratory, Department of Biochemistry and Microbial Genetics, Biological Research Institute "Clemente Estable", Montevideo, Uruguay
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Hydrogenotrophic methanogen strain of Methanospirillum from anaerobic digester fed with agro-industrial waste. Biologia (Bratisl) 2020. [DOI: 10.2478/s11756-020-00559-y] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
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12
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Abstract
Pyrite is the most abundant iron−sulfur mineral in sediments. Over geological times, its burial controlled oxygen levels in the atmosphere and sulfate concentrations in seawater. However, the mechanism of pyrite formation in sediments is still being debated. We show that lithotrophic microorganisms can mediate the transformation of FeS and H2S to FeS2 at ambient temperature if metabolically coupled to methane-producing archaea. Our results provide insights into a metabolic relationship that could sustain part of the deep biosphere and lend support to the iron−sulfur-world theory that postulated FeS transformation to FeS2 as a key energy-delivering reaction for life to emerge. The exergonic reaction of FeS with H2S to form FeS2 (pyrite) and H2 was postulated to have operated as an early form of energy metabolism on primordial Earth. Since the Archean, sedimentary pyrite formation has played a major role in the global iron and sulfur cycles, with direct impact on the redox chemistry of the atmosphere. However, the mechanism of sedimentary pyrite formation is still being debated. We present microbial enrichment cultures which grew with FeS, H2S, and CO2 as their sole substrates to produce FeS2 and CH4. Cultures grew over periods of 3 to 8 mo to cell densities of up to 2 to 9 × 106 cells per mL−1. Transformation of FeS with H2S to FeS2 was followed by 57Fe Mössbauer spectroscopy and showed a clear biological temperature profile with maximum activity at 28 °C and decreasing activities toward 4 °C and 60 °C. CH4 was formed concomitantly with FeS2 and exhibited the same temperature dependence. Addition of either penicillin or 2-bromoethanesulfonate inhibited both FeS2 and CH4 production, indicating a coupling of overall pyrite formation to methanogenesis. This hypothesis was supported by a 16S rRNA gene-based phylogenetic analysis, which identified at least one archaeal and five bacterial species. The archaeon was closely related to the hydrogenotrophic methanogen Methanospirillum stamsii, while the bacteria were most closely related to sulfate-reducing Deltaproteobacteria, as well as uncultured Firmicutes and Actinobacteria. Our results show that pyrite formation can be mediated at ambient temperature through a microbially catalyzed redox process, which may serve as a model for a postulated primordial iron−sulfur world.
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Parshina SN, Strepis N, Aalvink S, Nozhevnikova AN, Stams AJM, Sousa DZ. Trichococcus shcherbakoviae sp. nov., isolated from a laboratory-scale anaerobic EGSB bioreactor operated at low temperature. Int J Syst Evol Microbiol 2019; 69:529-534. [PMID: 30605071 DOI: 10.1099/ijsem.0.003193] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023] Open
Abstract
A new species of the genus Trichococcus, strain Art1T, was isolated from a psychrotolerant syntrophic propionate-oxidizing consortium, obtained before from a low-temperature EGSB reactor fed with a mixture of VFAs (acetate, propionate and butyrate). The 16S rRNA gene sequence of strain Art1T was highly similar to those of other Trichococcus species (99.7-99.9 %) but digital DNA-DNA hybridization values were lower than those recommended for the delineation of a novel species, indicating that strain Art1T is a novel species of the genus Trichococcus. Cells of strain Art1T are non-motile cocci with a diameter of 0.5-2.0 µm and were observed singularly, in pairs, short chains and irregular conglomerates. Cells of Art1T stained Gram-positive and produced extracellular polymeric substances . Growth was optimal at pH 6-7.5 and cells could grow in a temperature range of from -2 to 30 °C (optimum 25-30 °C). Strain Art1T can degrade several carbohydrates, and the main products from glucose fermentation are lactate, acetate, formate and ethanol. The genomic DNA G+C content of strain Art1T is 46.7 %. The major components of the cellular fatty acids are C16 : 1 ω9c, C16 : 0 and C18 : 1 ω9c. Based on genomic and physiological characteristics of strain Art1T, a new species of the genus Trichococcus, Trichococcusshcherbakoviae, is proposed. The type strain of Trichococcusshcherbakoviae is Art1T (=DSM 107162T = VKM B-3260T).
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Affiliation(s)
- Sofiya Nikolaevna Parshina
- 1Laboratory of Microbiology of Anthropogenic Habitats of Winogradsky Institute of Microbiology, Federal State Institution «Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences», Leninsky prosp. 33, b.2, 119071 Moscow, Russia.,2Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands
| | - Nikolaos Strepis
- 2Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands.,3Laboratory of Systems and Synthetic Biology, Wageningen University and Research, 6708 WE Stippeneng, The Netherlands
| | - Steven Aalvink
- 2Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands
| | - Alla N Nozhevnikova
- 1Laboratory of Microbiology of Anthropogenic Habitats of Winogradsky Institute of Microbiology, Federal State Institution «Federal Research Centre «Fundamentals of Biotechnology» of the Russian Academy of Sciences», Leninsky prosp. 33, b.2, 119071 Moscow, Russia
| | - Alfons J M Stams
- 2Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands
| | - Diana Z Sousa
- 2Laboratory of Microbiology, Wageningen University and Research, 6708 WE Wageningen, The Netherlands
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Danshita T, Miyaoka Y, Sumino H, Iguchi A, Yamaguchi T, Syutsubo K. Evaluation of process performance and retained sludge properties of a psychrophilic UASB reactor for treatment of iso-plophyl alcohol (2-propanol)-containing wastewater. JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH. PART A, TOXIC/HAZARDOUS SUBSTANCES & ENVIRONMENTAL ENGINEERING 2018; 53:1177-1184. [PMID: 30596343 DOI: 10.1080/10934529.2018.1530334] [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: 03/28/2018] [Accepted: 05/14/2018] [Indexed: 06/09/2023]
Abstract
In this study, a continuous feeding experiment was conducted with synthetic iso-plophyl alcohol (2-propanol)-containing wastewater using a lab-scale psychrophilic UASB reactor to evaluate process performance and retained sludge properties. For smooth acclimation, methanogenic granular sludge was seeded and a proportion of 2-propanol in the synthetic wastewater containing sucrose and volatile fatty acids was increased stepwise from 0% to 30%, 60% and then 90% of COD (chemical oxygen demand). As a result, after a 4-week period for acclimation to 2-propanol degradation, a COD removal rate of 95% was achieved at an organic loading rate (OLR) of 8.4 kg COD/m3/day. Additionally, the physical properties of the retained granular sludge were maintained even when the reactor was supplied with 2-propanol-rich wastewater for more than 200 days. From the batch assays using serum bottles, methanogenic degradation of 2-propanol was observed with acetone accumulation. By comparison, 2-propanol degradation was clearly inhibited in the presence of chloroform as a specific inhibitor of methanogen. A domain archaeal community structure analysis targeting 16S rRNA genes showed the relative abundance of the genus Methanospillium was increased in the 2-propanol acclimated sludge. These results suggested Methanospillium related species in the granular sludge appreciably contributed to the direct degradation of 2-proapanol into acetone under an anaerobic condition.
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Affiliation(s)
- Tsuyoshi Danshita
- a Department of Energy and Environmental Science , Nagaoka University of Technology , Nagaoka , Niigata , Japan
- b Center for Regional Environmental Research, National Institute for Environmental Studies , Tsukuba , Ibaraki , Japan
| | - Yuma Miyaoka
- a Department of Energy and Environmental Science , Nagaoka University of Technology , Nagaoka , Niigata , Japan
- b Center for Regional Environmental Research, National Institute for Environmental Studies , Tsukuba , Ibaraki , Japan
| | - Haruhiko Sumino
- c Department of Civil Engineering , National Institute of Technology, Gifu College , Motosu , Gifu , Japan
| | - Akinori Iguchi
- d Faculty of Applied Life Sciences , Niigata University of Pharmacy and Applied Life Sciences , Akiba-ku , Niigata , Japan
| | - Takashi Yamaguchi
- e Department of Science of Technology Innovation , Nagaoka University of Technology , Nagaoka , Niigata , Japan
| | - Kazuaki Syutsubo
- b Center for Regional Environmental Research, National Institute for Environmental Studies , Tsukuba , Ibaraki , Japan
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15
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Wang X, Li Z, Bai X, Zhou X, Cheng S, Gao R, Sun J. Study on improving anaerobic co-digestion of cow manure and corn straw by fruit and vegetable waste: Methane production and microbial community in CSTR process. BIORESOURCE TECHNOLOGY 2018; 249:290-297. [PMID: 29054058 DOI: 10.1016/j.biortech.2017.10.038] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2017] [Revised: 10/03/2017] [Accepted: 10/07/2017] [Indexed: 06/07/2023]
Abstract
Based on continuous anaerobic co-digestion of cow manure with available carbon slowly released corn straw, the effect of adding available carbon quickly released fruit and vegetable waste (FVW) was explored, meanwhile microbial community variation was studied in this study. When the FVW added was 5% and 1%, the methane production of the cow manure and corn straw was improved, and the start-up process was shortened. With higher proportion of FVW to 5%, the performance was superior with a mean methane yield increase of 22.4%, and a greater variation of bacterial communities was observed. FVW enhanced the variation of the bacterial communities. The microbial community structure changed during fermentation and showed a trend toward a diverse and balance system. Therefore, the available carbon quickly released FVW was helpful to improve the anaerobic co-digestion of the cow manure and available carbon slowly released corn straw.
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Affiliation(s)
- Xuemei Wang
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Zifu Li
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China.
| | - Xue Bai
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Xiaoqin Zhou
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Sikun Cheng
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Ruiling Gao
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
| | - Jiachen Sun
- School of Energy and Environmental Engineering, Beijing Key Laboratory of Resource-Oriented Treatment of Industrial Pollutants, International Science and Technology Cooperation Base for Environmental and Energy Technology of MOST, University of Science and Technology Beijing, Beijing 100083, PR China
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16
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Anaerobic digestion of pig manure supernatant at high ammonia concentrations characterized by high abundances of Methanosaeta and non-euryarchaeotal archaea. Sci Rep 2017; 7:15077. [PMID: 29118356 PMCID: PMC5678120 DOI: 10.1038/s41598-017-14527-1] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/03/2017] [Accepted: 10/06/2017] [Indexed: 11/22/2022] Open
Abstract
We examined the effect of ammonium and temperature on methane production in high rate upflow anaerobic sludge bed reactors treating pig manure supernatant. We operated four reactors at two ammonium concentrations (‘low’ at 1.9, ‘high’ at 3.7 g L−1, termed LA and HA reactors, respectively) and at variable temperatures over 358 days. Archaeal and bacterial communities were characterized by Illumina sequencing of 16S rRNA amplicons. Ammonium was a major selective factor for bacterial and archaeal community structure. After ~200 days of adaptation to high ammonium levels, acetate and propionate removal and methane production improved substantially in HA reactors. Aceticlastic Methanosaeta was abundant and positively correlated to methane yield in the HA reactors, whereas Methanosarcina was more abundant in LA reactors. Furthermore, a group of monophyletic OTUs that was related to Thaumarchaeota in phylogenetic analysis was highly abundant in the archaeal communities, particularly in the HA reactors. The most abundant bacterial OTU in LA reactors, representing Syntrophomonadaceae, was also positively correlated to methane yield in the HA reactors, indicating its importance in methane production under ammonia stress. In conclusion, efficient methane production, involving aceticlastic methanogenesis by Methanosaeta took place in the reactors at free ammonia concentrations as high as 1 g L−1.
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17
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Taubner RS, Rittmann SKMR. Method for Indirect Quantification of CH4 Production via H2O Production Using Hydrogenotrophic Methanogens. Front Microbiol 2016; 7:532. [PMID: 27199898 PMCID: PMC4850170 DOI: 10.3389/fmicb.2016.00532] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/19/2015] [Accepted: 03/31/2016] [Indexed: 01/01/2023] Open
Abstract
Hydrogenotrophic methanogens are an intriguing group of microorganisms from the domain Archaea. Methanogens exhibit extraordinary ecological, biochemical, and physiological characteristics and possess a huge biotechnological potential. Yet, the only possibility to assess the methane (CH4) production potential of hydrogenotrophic methanogens is to apply gas chromatographic quantification of CH4. In order to be able to effectively screen pure cultures of hydrogenotrophic methanogens regarding their CH4 production potential we developed a novel method for indirect quantification of the volumetric CH4 production rate by measuring the volumetric water production rate. This method was established in serum bottles for cultivation of methanogens in closed batch cultivation mode. Water production was estimated by determining the difference in mass increase in a quasi-isobaric setting. This novel CH4 quantification method is an accurate and precise analytical technique, which can be used to rapidly screen pure cultures of methanogens regarding their volumetric CH4 evolution rate. It is a cost effective alternative determining CH4 production of methanogens over CH4 quantification by using gas chromatography, especially if applied as a high throughput quantification method. Eventually, the method can be universally applied for quantification of CH4 production from psychrophilic, thermophilic and hyperthermophilic hydrogenotrophic methanogens.
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Affiliation(s)
- Ruth-Sophie Taubner
- Research Platform: ExoLife, University of ViennaVienna, Austria; Institute of Astrophysics, University of ViennaVienna, Austria; Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of ViennaVienna, Austria
| | - Simon K-M R Rittmann
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna Vienna, Austria
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18
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Zhou J, Yan BH, Wang Y, Yong XY, Yang ZH, Jia HH, Jiang M, Wei P. Effect of steam explosion pretreatment on the anaerobic digestion of rice straw. RSC Adv 2016. [DOI: 10.1039/c6ra15330e] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Steam explosion pretreatment on the anaerobic digestion of rice straw.
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Affiliation(s)
- J. Zhou
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
- Bioenergy Research Institute
| | - B. H. Yan
- Lab of Waste Valorisation and Water Reuse
- Qingdao Institute of Bioenergy and Bioprocess Technology
- Chinese Academy of Sciences
- Qingdao 266101
- China
| | - Y. Wang
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
| | - X. Y. Yong
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
- Bioenergy Research Institute
| | - Z. H. Yang
- Key Laboratory of Material and Chemical Engineering
- Nanjing Tech University
- Nanjing 210009
- China
| | - H. H. Jia
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
- Bioenergy Research Institute
| | - M. Jiang
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
| | - P. Wei
- College of Biotechnology and Pharmaceutical Engineering
- Nanjing Tech University
- Nanjing 211816
- China
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19
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Holmes D, Smith J. Biologically Produced Methane as a Renewable Energy Source. ADVANCES IN APPLIED MICROBIOLOGY 2016; 97:1-61. [PMID: 27926429 DOI: 10.1016/bs.aambs.2016.09.001] [Citation(s) in RCA: 55] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Methanogens are a unique group of strictly anaerobic archaea that are more metabolically diverse than previously thought. Traditionally, it was thought that methanogens could only generate methane by coupling the oxidation of products formed by fermentative bacteria with the reduction of CO2. However, it has recently been observed that many methanogens can also use electrons extruded from metal-respiring bacteria, biocathodes, or insoluble electron shuttles as energy sources. Methanogens are found in both human-made and natural environments and are responsible for the production of ∼71% of the global atmospheric methane. Their habitats range from the human digestive tract to hydrothermal vents. Although biologically produced methane can negatively impact the environment if released into the atmosphere, when captured, it can serve as a potent fuel source. The anaerobic digestion of wastes such as animal manure, human sewage, or food waste produces biogas which is composed of ∼60% methane. Methane from biogas can be cleaned to yield purified methane (biomethane) that can be readily incorporated into natural gas pipelines making it a promising renewable energy source. Conventional anaerobic digestion is limited by long retention times, low organics removal efficiencies, and low biogas production rates. Therefore, many studies are being conducted to improve the anaerobic digestion process. Researchers have found that addition of conductive materials and/or electrically active cathodes to anaerobic digesters can stimulate the digestion process and increase methane content of biogas. It is hoped that optimization of anaerobic digesters will make biogas more readily accessible to the average person.
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Taubner RS, Schleper C, Firneis MG, Rittmann SKMR. Assessing the Ecophysiology of Methanogens in the Context of Recent Astrobiological and Planetological Studies. Life (Basel) 2015; 5:1652-86. [PMID: 26703739 PMCID: PMC4695842 DOI: 10.3390/life5041652] [Citation(s) in RCA: 42] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/08/2015] [Revised: 10/15/2015] [Accepted: 11/10/2015] [Indexed: 12/31/2022] Open
Abstract
Among all known microbes capable of thriving under extreme and, therefore, potentially extraterrestrial environmental conditions, methanogens from the domain Archaea are intriguing organisms. This is due to their broad metabolic versatility, enormous diversity, and ability to grow under extreme environmental conditions. Several studies revealed that growth conditions of methanogens are compatible with environmental conditions on extraterrestrial bodies throughout the Solar System. Hence, life in the Solar System might not be limited to the classical habitable zone. In this contribution we assess the main ecophysiological characteristics of methanogens and compare these to the environmental conditions of putative habitats in the Solar System, in particular Mars and icy moons. Eventually, we give an outlook on the feasibility and the necessity of future astrobiological studies concerning methanogens.
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Affiliation(s)
- Ruth-Sophie Taubner
- Research Platform: ExoLife, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
- Institute of Astrophysics, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
| | - Christa Schleper
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria.
| | - Maria G Firneis
- Research Platform: ExoLife, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
- Institute of Astrophysics, University of Vienna, Türkenschanzstraße 17, 1180 Vienna, Austria.
| | - Simon K-M R Rittmann
- Archaea Biology and Ecogenomics Division, Department of Ecogenomics and Systems Biology, University of Vienna, Althanstraße 14, 1090 Vienna, Austria.
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22
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Kallistova AY, Goel G, Nozhevnikova AN. Microbial diversity of methanogenic communities in the systems for anaerobic treatment of organic waste. Microbiology (Reading) 2014. [DOI: 10.1134/s0026261714050142] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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