1
|
Variation in the Distribution of Hydrogen Producers from the Clostridiales Order in Biogas Reactors Depending on Different Input Substrates. ENERGIES 2018. [DOI: 10.3390/en11123270] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
With growing demand for clean and cheap energy resources, biogas production is emerging as an ideal solution, as it provides relatively cheap and clean energy, while also tackling the problematic production of excessive organic waste from crops and animal agriculture. Behind this process stands a variety of anaerobic microorganisms, which turn organic substrates into valuable biogas. The biogas itself is a mixture of gases, produced mostly as metabolic byproducts of the microorganisms, such as methane, hydrogen, or carbon dioxide. Hydrogen itself figures as a potent bio-fuel, however in many bioreactors it serves as the main substrate of methanogenesis, thus potentially limiting biogas yield. With help of modern sequencing techniques, we tried to evaluate the composition in eight bioreactors using different input materials, showing shifts in the microbial consortia depending on the substrate itself. In this paper, we provide insight on the occurrence of potentially harmful microorganisms such as Clostridium novyi and Clostridium septicum, as well as key genera in hydrogen production, such as Clostridium stercorarium, Mobilitalea sp., Herbinix sp., Herbivorax sp., and Acetivibrio sp.
Collapse
|
2
|
|
3
|
Li R, Duan N, Zhang Y, Liu Z, Li B, Zhang D, Dong T. Anaerobic co-digestion of chicken manure and microalgae Chlorella sp.: Methane potential, microbial diversity and synergistic impact evaluation. WASTE MANAGEMENT (NEW YORK, N.Y.) 2017. [PMID: 28648747 DOI: 10.1016/j.wasman.2017.06.028] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Anaerobic digestion (AD) is a promising alternative for livestock manure management. This paper presents the experimental results obtained through a batch experiment by using chicken manure (CM) and microalgae Chlorella sp. as co-substrates. The effect of co-digestion was evaluated by varying CM to Chlorella sp. ratios (0:10, 2:8, 4:6, 6:4, 8:2, 10: 0 based on the volatile solids (VS)). The major objective of this study is to evaluate the feasibility and synergistic impact of co-digestion of CM and Chlorella sp. Enhanced 14.20% and 76.86% methane production than CM and Chlorella sp. mono-digestion respectively was achieved in co-digestion at the ratio 8:2. In addition, the co-digestion at the ratio 8:2 showed significantly higher methane yield than the weighted average of the individual substrates' specific methane yield (WSMY), indicating strong synergy effect. The Illumina Miseq sequencing analysis showed that the AD process suppressed the acetoclastic methanogenesis Methanosaeta content; but partly enhanced hydrogenotrophic methanogenesis Methanosarcina, Methanospirillum and Methanobacterium, which was responsible for the methane production. The pre-treated microalgae was then introduced at the optimal ratio 8:2 to estimate the effect of pre-treatment of microalgae on AD process. However, the pre-treatment exhibited no positive effect.
Collapse
Affiliation(s)
- Ruirui Li
- Laboratory of Environment-Enhancing Energy (E2E) and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Na Duan
- Laboratory of Environment-Enhancing Energy (E2E) and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China.
| | - Yuanhui Zhang
- Laboratory of Environment-Enhancing Energy (E2E) and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China; Department of Agricultural and Biological Engineering, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
| | - Zhidan Liu
- Laboratory of Environment-Enhancing Energy (E2E) and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Baoming Li
- Laboratory of Environment-Enhancing Energy (E2E) and Key Laboratory of Agricultural Engineering in Structure and Environment, Ministry of Agriculture, College of Water Resources and Civil Engineering, China Agricultural University, Beijing 100083, China
| | - Dongming Zhang
- Shandong Minhe Biotech Limited Company, Yantai 265600, China
| | - Taili Dong
- Shandong Minhe Biotech Limited Company, Yantai 265600, China
| |
Collapse
|
4
|
Zhao Z, Zhang Y, Yu Q, Dang Y, Li Y, Quan X. Communities stimulated with ethanol to perform direct interspecies electron transfer for syntrophic metabolism of propionate and butyrate. WATER RESEARCH 2016; 102:475-484. [PMID: 27403870 DOI: 10.1016/j.watres.2016.07.005] [Citation(s) in RCA: 151] [Impact Index Per Article: 18.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/07/2016] [Revised: 06/18/2016] [Accepted: 07/03/2016] [Indexed: 05/28/2023]
Abstract
Direct interspecies electron transfer (DIET) has been considered as an alternative to interspecies H2 transfer (IHT) for syntrophic metabolism, but the microorganisms capable of metabolizing the key intermediates, such as propionate and butyrate, via DIET have yet to be described. A strategy of culturing the enrichments with ethanol as a DIET substrate to stimulate the communities for the syntrophic metabolism of propionate and/or butyrate was proposed in this study. The results showed that the syntrophic propionate and/or butyrate degradation was significantly improved in the ethanol-stimulated reactor when propionate/butyrate was the sole carbon source. The conductivity of the ethanol-stimulated enrichments was as 5 folds (for propionate)/76 folds (for butyrate) as that of the traditional enrichments (never ethanol fed). Microbial community analysis revealed that Geobacter species known to proceed DIET were only detected in the ethanol-stimulated enrichments. Together with the significant increase of Methanosaeta and Methanosarcina species in these enrichments, the potential DIET between Geobacter and Methanosaeta or Methanosarcina species might be established to improve the syntrophic propionate and/or butyrate degradation. Further experiments demonstrated that granular activated carbon (GAC) could improve the syntrophic metabolism of propionate and/or butyrate of the ethanol-stimulated enrichments, while almost no effects on the traditional enrichments. Also, the high H2 partial pressure could inhibit the syntrophic propionate and/or butyrate degradation of the traditional enrichments, but its effect on that of the ethanol-stimulated enrichments was negligible.
Collapse
Affiliation(s)
- Zhiqiang Zhao
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Yaobin Zhang
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China.
| | - Qilin Yu
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Yan Dang
- Beijing Key Lab for Source Control Technology of Water Pollution, Beijing Forestry University, 35 Tsinghua East Road, Beijing, 100083, China; Department of Microbiology, University of Massachusetts, Amherst, MA, 01003-9298, USA
| | - Yang Li
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| | - Xie Quan
- Key Laboratory of Industrial Ecology and Environmental Engineering (Dalian University of Technology), Ministry of Education, School of Environmental Science and Technology, Dalian University of Technology, Dalian, 116024, China
| |
Collapse
|
5
|
Morita M, Malvankar NS, Franks AE, Summers ZM, Giloteaux L, Rotaru AE, Rotaru C, Lovley DR. Potential for direct interspecies electron transfer in methanogenic wastewater digester aggregates. mBio 2011; 2:e00159-11. [PMID: 21862629 PMCID: PMC3157894 DOI: 10.1128/mbio.00159-11] [Citation(s) in RCA: 308] [Impact Index Per Article: 23.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 08/02/2011] [Indexed: 01/01/2023] Open
Abstract
Mechanisms for electron transfer within microbial aggregates derived from an upflow anaerobic sludge blanket reactor converting brewery waste to methane were investigated in order to better understand the function of methanogenic consortia. The aggregates were electrically conductive, with conductivities 3-fold higher than the conductivities previously reported for dual-species aggregates of Geobacter species in which the two species appeared to exchange electrons via interspecies electron transfer. The temperature dependence response of the aggregate conductance was characteristic of the organic metallic-like conductance previously described for the conductive pili of Geobacter sulfurreducens and was inconsistent with electron conduction through minerals. Studies in which aggregates were incubated with high concentrations of potential electron donors demonstrated that the aggregates had no significant capacity for conversion of hydrogen to methane. The aggregates converted formate to methane but at rates too low to account for the rates at which that the aggregates syntrophically metabolized ethanol, an important component of the reactor influent. Geobacter species comprised 25% of 16S rRNA gene sequences recovered from the aggregates, suggesting that Geobacter species may have contributed to some but probably not all of the aggregate conductivity. Microorganisms most closely related to the acetate-utilizing Methanosaeta concilii accounted for more than 90% of the sequences that could be assigned to methane producers, consistent with the poor capacity for hydrogen and formate utilization. These results demonstrate for the first time that methanogenic wastewater aggregates can be electrically conductive and suggest that direct interspecies electron transfer could be an important mechanism for electron exchange in some methanogenic systems.
Collapse
Affiliation(s)
| | | | - Ashley E. Franks
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Zarath M. Summers
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Ludovic Giloteaux
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Amelia E. Rotaru
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Camelia Rotaru
- Civil and Environmental Engineering Department, University of Massachusetts, Amherst, Massachusetts, USA
| | - Derek R. Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| |
Collapse
|
6
|
Summers ZM, Fogarty HE, Leang C, Franks AE, Malvankar NS, Lovley DR. Direct exchange of electrons within aggregates of an evolved syntrophic coculture of anaerobic bacteria. Science 2010; 330:1413-5. [PMID: 21127257 DOI: 10.1126/science.1196526] [Citation(s) in RCA: 528] [Impact Index Per Article: 37.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Microbial consortia that cooperatively exchange electrons play a key role in the anaerobic processing of organic matter. Interspecies hydrogen transfer is a well-documented strategy for electron exchange in dispersed laboratory cultures, but cooperative partners in natural environments often form multispecies aggregates. We found that laboratory evolution of a coculture of Geobacter metallireducens and Geobacter sulfurreducens metabolizing ethanol favored the formation of aggregates that were electrically conductive. Sequencing aggregate DNA revealed selection for a mutation that enhances the production of a c-type cytochrome involved in extracellular electron transfer and accelerates the formation of aggregates. Aggregate formation was also much faster in mutants that were deficient in interspecies hydrogen transfer, further suggesting direct interspecies electron transfer.
Collapse
Affiliation(s)
- Zarath M Summers
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
| | | | | | | | | | | |
Collapse
|
7
|
Giraldo-Gomez E, Goodwin S, Switzenbaum MS. Influence of mass transfer limitations on determination of the half saturation constant for hydrogen uptake in a mixed-culture CH(4)-producing enrichment. Biotechnol Bioeng 2010; 40:768-76. [PMID: 18601180 DOI: 10.1002/bit.260400704] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Abstract
There is strong evidence in the literature supporting the existence of significant mass transfer limitations on the kinetics of exogenous H(2) consumption by methanogens. The half saturation constant for H (2) uptake by a mixed-culture, CH(4) producing enrichment was measured using an experimental protocol that avoided internal mass transfer limitations. The value obtained was two orders of magnitude smaller than any other previously reported. A mathematical model for acetogenic syntrophic associations was developed to check the capacity of H(2) as electron transporter between syntrophic partners. It was found that H(2) diffusion could account for the rate of transport of electrons between the syntrophic microorganisms and that formate is not a necessary intermediate. The possibility that formate may be an intermediate in this system was not ruled out. A Monod-type kinetic equation was modified to include the observed H(2) threshold effect. This modified equation was used to predict the CH(4)-production rate in a batch-fed digester. The results show that the external and internal H(2) pools are kinetically coupled.
Collapse
Affiliation(s)
- E Giraldo-Gomez
- Departments of Civil Engineering, University of Massachusetts at Amherst, Amherst, Massachusetts 01003, USA
| | | | | |
Collapse
|
8
|
Stams AJM, Plugge CM. Electron transfer in syntrophic communities of anaerobic bacteria and archaea. Nat Rev Microbiol 2009; 7:568-77. [PMID: 19609258 DOI: 10.1038/nrmicro2166] [Citation(s) in RCA: 701] [Impact Index Per Article: 46.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Interspecies electron transfer is a key process in methanogenic and sulphate-reducing environments. Bacteria and archaea that live in syntrophic communities take advantage of the metabolic abilities of their syntrophic partner to overcome energy barriers and break down compounds that they cannot digest by themselves. Here, we review the transfer of hydrogen and formate between bacteria and archaea that helps to sustain growth in syntrophic methanogenic communities. We also describe the process of reverse electron transfer, which is a key requirement in obligately syntrophic interactions. Anaerobic methane oxidation coupled to sulphate reduction is also carried out by syntrophic communities of bacteria and archaea but, as we discuss, the exact mechanism of this syntrophic interaction is not yet understood.
Collapse
Affiliation(s)
- Alfons J M Stams
- Laboratory of Microbiology, Wageningen University, Dreijenplein 10, 6703 HB Wageningen, The Netherlands.
| | | |
Collapse
|
9
|
Porwal S, Kumar T, Lal S, Rani A, Kumar S, Cheema S, Purohit HJ, Sharma R, Singh Patel SK, Kalia VC. Hydrogen and polyhydroxybutyrate producing abilities of microbes from diverse habitats by dark fermentative process. BIORESOURCE TECHNOLOGY 2008; 99:5444-5451. [PMID: 18083024 DOI: 10.1016/j.biortech.2007.11.011] [Citation(s) in RCA: 74] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/31/2007] [Revised: 11/02/2007] [Accepted: 11/05/2007] [Indexed: 05/25/2023]
Abstract
Thirty five bacterial isolates from diverse environmental sources such as contaminated food, nitrogen rich soil, activated sludges from pesticide and oil refineries effluent treatment plants were found to belong to Bacillus, Bordetella, Enterobacter, Proteus, and Pseudomonas sp. on the basis of 16S rRNA gene sequence analysis. Under dark fermentative conditions, maximum hydrogen (H(2)) yields (mol/mol of glucose added) were recorded to be 0.68 with Enterobacter aerogenes EGU16 followed by 0.63 with Bacillus cereus EGU43 and Bacillus thuringiensis EGU45. H(2) constituted 63-69% of the total biogas evolved. Out of these 35 microbes, 18 isolates had the ability to produce polyhydroxybutyrate (PHB), which varied up to 500 mg/l of medium, equivalent to a yield of 66.6%. The highest PHB yield was recorded with B. cereus strain EGU3. Nine strains had high hydrolytic activities (zone of hydrolysis): lipase (34-38 mm) -Bacillus sphaericus strains EGU385, EGU399 and EGU542; protease (56-62 mm) -Bacillus sp. strains EGU444, EGU447 and EGU445; amylase (23 mm) -B. thuringiensis EGU378, marine bacterium strain EGU409 and Pseudomonas sp. strain EGU448. These strains with high hydrolytic activities had relatively low H(2) producing abilities in the range of 0.26-0.42 mol/mol of glucose added and only B. thuringiensis strain EGU378 had the ability to produce PHB. This is the first report among the non-photosynthetic microbes, where the same organism(s) -B. cereus strain EGU43 and B. thuringiensis strain EGU45, have been shown to produce H(2) - 0.63 mol/mol of glucose added and PHB - 420-435 mg/l medium.
Collapse
Affiliation(s)
- Shalini Porwal
- Microbial Biotechnology and Genomics, Institute of Genomics and Integrative Biology (IGIB), CSIR, Delhi University Campus, Mall Road, Delhi 110007, India
| | | | | | | | | | | | | | | | | | | |
Collapse
|
10
|
Aiyuk S, Forrez I, Lieven DK, van Haandel A, Verstraete W. Anaerobic and complementary treatment of domestic sewage in regions with hot climates--a review. BIORESOURCE TECHNOLOGY 2006; 97:2225-41. [PMID: 16055328 DOI: 10.1016/j.biortech.2005.05.015] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/23/2004] [Revised: 05/16/2005] [Accepted: 05/16/2005] [Indexed: 05/03/2023]
Abstract
This study presents a literature review on the treatment of domestic sewage in controlled environments having the anaerobic process and specifically the upflow anaerobic sludge blanket (UASB) concept as the core, under natural hot conditions. The UASB process application is however beset by the preponderance of suspended solids, and the paper looks at its optimization via pre- and post-treatments to curb the prevailing problems, in the light of possible discharge and re-use/recycling/resource recovery, leading to efficient environmental protection. Pre-treatment clarification could be done with ferric chloride/polyelectrolyte, so that phosphate precipitates during the process. The pre-treated liquid phase can be submitted to a high rate anaerobic process, using the simple and robust UASB technology. In a subsequent post-treatment step, ammonium can be removed by ion exchange using a zeolite column through which the wastewater percolates after leaving the anaerobic digester. The various stages can also eliminate a large fraction of the pathogens present in the raw wastewater, mainly through the pre-treatment sedimentation and the ion exchange filtration. The sludge produced in the precipitation stage can be stabilized in a conventional anaerobic digester. Integration of the different treatment steps provides a sustainable technology to treat domestic sewage under hot climate conditions.
Collapse
Affiliation(s)
- Sunny Aiyuk
- Laboratory of Microbial Ecology and Technology (LabMET), Ghent University, Coupure Links 653, B-9000 Ghent, Belgium
| | | | | | | | | |
Collapse
|
11
|
Wu WM, Jain MK, Hickey RF, Zeikus JG. Perturbation of syntrophic isobutyrate and butyrate degradation with formate and hydrogen. Biotechnol Bioeng 2000; 52:404-11. [DOI: 10.1002/(sici)1097-0290(19961105)52:3<404::aid-bit6>3.0.co;2-o] [Citation(s) in RCA: 17] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
|
12
|
Stewart PS. A review of experimental measurements of effective diffusive permeabilities and effective diffusion coefficients in biofilms. Biotechnol Bioeng 1998; 59:261-72. [PMID: 10099336 DOI: 10.1002/(sici)1097-0290(19980805)59:3<261::aid-bit1>3.0.co;2-9] [Citation(s) in RCA: 192] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Experimental measurements of effective diffusive permeabilities and effective diffusion coefficients in biofilms are reviewed. Effective diffusive permeabilities, the parameter appropriate to the analysis of reaction-diffusion interactions, depend on solute type and biofilm density. Three categories of solute physical chemistry with distinct diffusive properties were distinguished by the present analysis. In order of descending mean relative effective diffusive permeability (De/Daq) these were inorganic anions or cations (0.56), nonpolar solutes with molecular weights of 44 or less (0.43), and organic solutes of molecular weight greater than 44 (0.29). Effective diffusive permeabilities decrease sharply with increasing biomass volume fraction suggesting a serial resistance model of diffusion in biofilms as proposed by Hinson and Kocher (1996). A conceptual model of biofilm structure is proposed in which each cell is surrounded by a restricted permeability envelope. Effective diffusion coefficients, which are appropriate to the analysis of transient penetration of nonreactive solutes, are generally similar to effective diffusive permeabilities in biofilms of similar composition. In three studies that examine diffusion of very large molecular weight solutes (>5000) in biofilms, the average ratio of the relative effective diffusion coefficient of the large solute to the relative effective diffusion coefficient of either sucrose or fluorescein was 0.64, 0.61, and 0.36. It is proposed that large solutes are effectively excluded from microbial cells, that small solutes partition into and diffuse within cells, and that ionic solutes are excluded from cells but exhibit increased diffusive permeability (but decreased effective diffusion coefficients) due to sorption to the biofilm matrix.
Collapse
Affiliation(s)
- P S Stewart
- Center for Biofilm Engineering and Department of Chemical Engineering, Montana State University, Bozeman, Montana 59717, USA.
| |
Collapse
|
13
|
Krylova NI, Conrad R. Thermodynamics of propionate degradation in methanogenic paddy soil. FEMS Microbiol Ecol 1998. [DOI: 10.1111/j.1574-6941.1998.tb00512.x] [Citation(s) in RCA: 35] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
|
14
|
J.W.H. S, Elferink O, Visser A, Hulshoff Pol LW, Stams AJ. Sulfate reduction in methanogenic bioreactors. FEMS Microbiol Rev 1994. [DOI: 10.1111/j.1574-6976.1994.tb00130.x] [Citation(s) in RCA: 195] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022] Open
|
15
|
Kitsos HM, Roberts RS, Jones WJ, Tornabene TG. An experimental study of mass diffusion and reaction rate in an anaerobic biofilm. Biotechnol Bioeng 1992; 39:1141-6. [DOI: 10.1002/bit.260391110] [Citation(s) in RCA: 27] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/05/2022]
|
16
|
Goodwin S, Giraldo-Gomez E, Mobarry B, Switzenbaum MS. Comparison of diffusion and reaction rates in anaerobic microbial aggregates. MICROBIAL ECOLOGY 1991; 22:161-174. [PMID: 24194334 DOI: 10.1007/bf02540221] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/16/1990] [Indexed: 06/02/2023]
Abstract
The ability of hydrogen diffusion to account for the rates of methane production in microbial aggregates was studied in a defined coculture consisting of a sulfate reducer grown as a syntrophic hydrogen producer in the absence of sulfate and a methanogen. The hydrogen uptake kinetics of the methanogen were determined using the infinite dilution technique. The maximum hydrogen uptake velocity was 7.1 nmol/min/μg protein and the half saturation constant for hydrogen uptake was 386 nmol/liter. A threshold of 28 nmol/liter below which no further hydrogen consumption occurred was observed. The reconstituted co-culture was shown to produce methane at rates similar to mixed culture enrichments grown on lactate. The diffusion model demonstrated that for the particular system studied, the rates of hydrogen diffusion could account for the overall rate of methane production.
Collapse
Affiliation(s)
- S Goodwin
- Department of Microbiology, University of Massachusetts, 01003, Amherst, Massachusetts, USA
| | | | | | | |
Collapse
|
17
|
Pavlostathis SG, Giraldo‐Gomez E. Kinetics of anaerobic treatment: A critical review. ACTA ACUST UNITED AC 1991. [DOI: 10.1080/10643389109388424] [Citation(s) in RCA: 269] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
|