Consulta: subjectFacets:"Methanogenesis"
Registros recuperados: 13
Data/hora: 09/06/2024 08:38:40

Performance of biofilm carriers in anaerobic digestion of sisal leaf waste leachate
Provedor de dados: 69
Autores: Mshandete,Anthony Manoni; Björnsson,Lovisa; Kivaisi,Amelia Kajumulo; Rubindamayugi,Mugassa Steven Thomas; Mattiasson,Bo.
Three methanogenic biofilm bioreactors were studied to evaluate the performance of three types of carriers. The carrier material were consisted of sisal fibre waste, pumice stone and porous glass beads, and the bioprocess evaluated was the methanogenesis anaerobic digestion of sisal leaf waste leachate. Process performance was investigated by increasing the organic loading rate (OLR) step-wise. The best results were obtained from the bioreactor packed with sisal fibre waste. It had the highest chemical oxygen demand (COD) removal efficiencies in the range of 80-93% at OLRs in the range of 2.4-25 g COD L-1d-1. The degradation pattern of volatile fatty acids (VFAs) showed that the degradation of propionate was limiting at higher OLRs. The stable pH and...
Tipo: Journal article
Palavras-chave: Biogas; Methanogenesis; Packed-bed bioreactors; Packing media.
Ano: 2008
URL: http://www.scielo.cl/scielo.php?script=sci_arttext&pid=S0717-34582008000100009

Complex coupled metabolic and prokaryotic community responses to increasing temperatures in anaerobic marine sediments: critical temperatures and substrate changes
Provedor de dados: 5
Autores: Roussel, Erwan; Cragg, Barry A.; Webster, Gordon; Sass, Henrik; Tang, Xiaohong; Williams, Angharad S.; Gorra, Roberta; Weightman, Andrew J.; Parkes, R. John.
The impact of temperature (0 - 80°C) on anaerobic biogeochemical processes and prokaryotic communities in marine sediments (tidal flat) was investigated in slurries for up to 100 days. Temperature had a non-linear effect on biogeochemistry and prokaryotes with rapid changes over small temperature intervals. Some activities (e.g. methanogenesis) had multiple “windows” within a large temperature range (~10 - 80°C). Others, including acetate oxidation, had maximum activities within a temperature zone, which varied with electron acceptor (metal oxide [up to ~34°C] and sulphate [up to ~50°C]). Substrates for sulphate reduction changed from predominantly acetate below, and H2 above, a 43°C critical temperature; along with changes in activation energies and types...
Tipo: Text
Palavras-chave: Sediment; Temperature; Anaerobic processes; Chemoorganotrophic; Chemolithotrophic; Mineralisation; Sulphate reduction; Methanogenesis; Acetogenesis.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00273/38464/36883.pdf

Methanogenic activity and diversity in the centre of the Amsterdam Mud Volcano, Eastern Mediterranean Sea
Provedor de dados: 5
Autores: Lazar, Cassandre; Parkes, R. John; Cragg, Barry A.; L'Haridon, Stephane; Toffin, Laurent.
Marine mud volcanoes are geological structures emitting large amounts of methane from their active centres. The Amsterdam mud volcano (AMV), located in the Anaximander Mountains south of Turkey, is characterized by intense active methane seepage produced in part by methanogens. To date, information about the diversity or the metabolic pathways used by the methanogens in active centres of marine mud volcanoes is limited. 14C-radiotracer measurements showed that methylamines/methanol, H2/CO2 and acetate were used for methanogenesis in the AMV. Methylotrophic methanogenesis was measured all along the sediment core, Methanosarcinales affiliated sequences were detected using archaeal 16S PCR-DGGE and mcrA gene libraries, and enrichments of methanogens showed...
Tipo: Text
Palavras-chave: Methanogenesis; McrA; Archaea.
Ano: 2012
URL: http://archimer.ifremer.fr/doc/00087/19795/17538.pdf

Interrelations entre des communautes mixtes de bacteries anaerobies isolees de sediments marins
Provedor de dados: 5
Autores: Marty, D.
The mineralization of cellulose was examined in mono and cocultures of marine anaerobic bacteria (cellulolytic bacteria, fermentative non-cellulolytic bacteria and methane-producing bacteria). These studies displayed interactions between these groups of microorganisms: inhibition relationships (inhibition of methanogens during active growth of fermentative bacteria) and syntrophic relationships (growth of fermentative non-cellulolytic bacteria depended on metabolites produced by cellulolytic bacteria; increased in rate of cellulose hydrolysis in presence of fermentative non-cellulolytic bacteria; interspecies H sub(2) transfer reaction between fermentative bacteria and methane-producing bacteria).
Tipo: Text
Palavras-chave: Biogeochemistry; Sedimentation; Sediments; Fermentation; Mineralization; Cellulose; Methanogenesis; Interspecific relationships; Anaerobic bacteria.
Ano: 1984
URL: http://archimer.ifremer.fr/doc/1984/acte-948.pdf

Production, consumption, and migration of methane in accretionary prism of southwestern Taiwan
Provedor de dados: 5
Autores: Chen, Nai-chen; Yang, Tsanyao Frank; Hong, Wei-li; Chen, Hsuan-wen; Chen, Hsiao-chi; Hu, Ching-yi; Huang, Yu-chun; Lin, Saulwood; Lin, Li-hung; Su, Chih-chieh; Liao, Wei-zhi; Sun, Chih-hsien; Wang, Pei-ling; Yang, Tao; Jiang, Shao-yong; Liu, Char-shine; Wang, Yunshuen; Chung, San-hsiung.
To systematically quantify the production, consumption and migration of methane along a continental margin, 210 sediment cores were collected from offshore southwestern Taiwan and analyzed for their gas and aqueous geochemistry. These data, combined with published results, were used to calculate the diffusive methane fluxes across different geochemical transitions and to develop scenarios of mass balance to constrain deep microbial and thermogenic methane production rates within the accretionary prism. The results showed that methane diffusive fluxes ranged from 2.71 × 10−3 to 2.78 × 10−1 and from ‒1.88 × 10−1 to 3.97 mmol m−2 d−1 at the sulfate-methane-transition-zone (SMTZ) and sediment-seawater interfaces, respectively. High methane fluxes tend to be...
Tipo: Text
Palavras-chave: Thermal maturation; Methanogenesis; Anaerobic methanotrophy; Methane efflux; Subduction; Taiwan.
Ano: 2017
URL: https://archimer.ifremer.fr/doc/00393/50412/51132.pdf

Methanogenesis and clay minerals diagenesis during the formation of dolomite nodules from the Tortonian marls of southern Spain
Provedor de dados: 5
Autores: Pierre, Catherine; Rouchy, Jean-marie; Blanc-valleron, Marie-madeleine; Etoubleau, Joel; Fouquet, Yves.
Dolomite nodules are widespread within the Tortonian marls of Fortuna and Lorca basins in southern Spain. They occur as large bodies of various forms (round, ovoid, tabular) that are parallel or secant relative to the stratification. They are massive and present sometimes internal conduits that are considered as drains used for the migration of fluids.  This study brings new results on the mineralogy and elemental and isotopic geochemistry of these dolomite nodules to better describe the processes that were occurring during their formation. The diagenetic reactions that have driven authigenic dolomite precipitation within the sediments involved on the one hand methanogenesis that produced 13C-poor CH4 and 13C-rich CO2, on the other hand carbonate and...
Tipo: Text
Palavras-chave: Authigenic dolomite nodules; Elemental geochemistry; Oxygen and carbon isotopes; Methanogenesis; Clay minerals diagenesis.
Ano: 2015
URL: https://archimer.ifremer.fr/doc/00266/37752/35803.pdf

Methane emission induced by short-chain organic acids in lowland soil
Provedor de dados: 90
Autores: Moscôso,Janielly Silva Costa; Silva,Leandro Souza da; Pujol,Stefen Barbosa; Giacomini,Sandro José; Severo,Fabiane Figueiredo; Marzari,Laura Brondani; Molin,Gustavo Dal.
ABSTRACT Methane (CH4) is the second major greenhouse gas after CO2, exerting a significant influence on the climate and the chemistry of the atmosphere. In lowland soil, acetate and H2/CO2 are the most important precursors of CH4 and formed from organic matter fermentation in an anaerobic environment, giving rise to short-chain organic acids (ethanoic, propanoic, and butanoic), depending on the type of crop residue and the soil management system. Ethanoic acid can be directly converted to CH4 by methanogenic microorganisms, but propanoic and butanoic acids must be converted to acetate before being converted to CH4. This study aimed to quantify, in isolation, the dynamics and CH4 emission potential of the three short-chain organic acids found in flooded...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Ethanoic acid; Butanoic acid; Propanoic acid; Methanogenesis; Irrigated rice.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0100-06832019000100412

Reconsidering rumen microbial consortia to enhance feed efficiency and reduce environmental impact of ruminant livestock production systems
Provedor de dados: 96
Autores: Firkins,Jeffrey Lynn.
Because cultivation-based approaches to assess rumen microbiology assess only the minority of microbial groups and can miss opportunities to assess important functions, molecular-based approaches have flourished in microbial ecology and have been adapted to the rumen. Current approaches are described herein, specifically for a robust adaptation to nutrition studies or future opportunities. These included automated profiling techniques, density gradient gel electrophoresis, and future adaption of microarray or high-throughput sequencing technologies. Based on current knowledge, a more holistic approach is needed to describe various functional groups of microbes within the context of how they influence, and are influenced by, the whole consortium...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biohydrogenation; Methanogenesis; Rumen fiber digestibility; Rumen microbial ecology.
Ano: 2010
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-35982010001300049

Potential and existing mechanisms of enteric methane production in ruminants
Provedor de dados: 63
Autores: Qiao,Junyi; Tan,Zhiliang; Wang,Min.
Enteric methane (CH4) emissions in ruminants have attracted considerable attention due to their impact on greenhouse gases and the contribution of agricultural practices to global warming. Over the last two decades, a number of approaches have been adopted to mitigate CH4 emissions. However, the mechanisms of methanogenesis have still not been fully defined. According to the genome sequences of M. ruminantium in the rumen and of M. AbM4 in the abomasum, the pathways of carbon dioxide (CO2) reduction and formate oxidation to CH4 have now been authenticated in ruminants. Furthermore, in the light of species or genera description of methanogens, the precursors of methanogenesis discovered in the rumen and research advances in related subjects, pathways of...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Methanogenesis; Carbon dioxide; Formate; Acetate; Methanol.
Ano: 2014
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-90162014000500013

Population Changes of Eubacteria, Sulfate-Reducing Bacteria and Methanogenic Archaea in an Anaerobic Reactor Processing Ethanol Distillery Vinasse
Provedor de dados: 52
Autores: Brown,Adis Ivonne Terry; Pozzi,Eloisa; Damianovic,Marcia Helena Rissato Zamariolli; Briones,Homero Enrique Urrutia; Ortiz,Leslie Ester Abarzúa; Pires,Eduardo Cleto.
Abstract The microbiological characterization by molecular techniques (DGGE and quantitative PCR) of Archaea, Bacteria domain and sulfate-reducing bacteria (SRB) from a laboratory scale Up-flow Anaerobic Sludge Blanket (UASB) processing sugar cane vinasse was performed during the operational phase with increasing organic loads. The organic load removal efficiency was between 97% and 75% for volumetric organic loads (VOL) in the range of 0.6 to 15.4 kgCOD.m-3.d−1 and for higher VOL (until 27.0 kgCOD.m-3 .d−1) the removal efficiency decreased to 48%. Archaea represented the majority of the estimated population (107 copies of 16S RNA ribosomal gene. mL-1) followed by bacteria (106 copies of 16S RNA ribosomal gene. mL-1) and sulfate-reducing bacteria (SRB)...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: UASB reactor; Microbial characterization; Methanogenesis; Sulfidogenesis; DGGE; Quantitative PCR.
Ano: 2019
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132019000100203

Biogenic gases in tropical floodplain river
Provedor de dados: 52
Autores: Ballester,Maria Victória Ramos; Santos,José Eduardo dos.
Analysis of the distribution of biogenic gases in the floodplain of the Mogi-Guaçu River (São Paulo, Brazil) enabled the establishment of a "redox hierarchy", in which the main channel was the most oxidizing environment, followed by Diogo Lake, with Infernão Lake having the most reducing conditions of the subsystems evaluated. Diogo Lake exported about 853.4 g C.m-2.year-1, of which, 14.6% was generated from methanogenesis and 36.7% by aerobic respiration. For Infernão Lake, these values were 2016 g C.m-2.year-1, 1.8 % and 41.5 %, respectively. Carbon export by these systems was predominantly in the form of CO2, which was responsible for the release of 728.78 g C.m-2.year-1 at Diogo Lake and 1979.72 g C.m-2. year-1 at Infernão Lake. Such patterns may...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Biogenic gases; Methanogenesis; Aerobic respiration; CO2 production.
Ano: 2001
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1516-89132001000200006

Ammonia determines transcriptional profile of microorganisms in anaerobic digestion
Provedor de dados: 58
Autores: Zhang,Nan; Peng,Huijuan; Li,Yong; Yang,Wenxiu; Zou,Yuneng; Duan,Huiguo.
ABSTRACT Anaerobic digestion is important for the management of livestock manure with high ammonia level. Although ammonia effects on anaerobic digestion have been comprehensively studied, the molecular mechanism underlying ammonia inhibition still remains elusive. In this study, based on metatranscriptomic analysis, the transcriptional profile of microbial community in anaerobic digestion under low (1500 mg L-1) and high NH4 + (5000 mg L-1) concentrations, respectively, were revealed. The results showed that high NH4 + concentrations significantly inhibited methane production but facilitated the accumulations of volatile fatty acids. The expression of methanogenic pathway was significantly inhibited by high NH4 + concentration but most of the other...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Anaerobic digestion; Ammonia; Pathway; Gene expression; Methanogenesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S1517-83822018000400770

Relationship between root exudation of organic carbon and physiological variables of irrigated rice cultivars
Provedor de dados: 65
Autores: Moscôso,Janielly Silva Costa; Silva,Leandro Souza da; Tarouco,Camila Peligrinotti; Nicoloso,Fernando Teixeira; Severo,Fabiane Figueiredo; Aita,Natália Tobin; Prigol,Luís Henrique Ferreira.
ABSTRACT:  Rhizospheric carbon resulting from root exudation is one of the substrates used by the soil microbiota, and reflects methane (CH4) emissions in anoxic environments such as irrigated rice cultivation. With the increase of the photosynthetic capacity of the plant in the reproductive period, there is greater accumulation of biomass which, in turn, increases the rate of root exudation. However, genotypic variations in the physiological aspects of rice plants may be related to the amount of root exudates. Ten cultivars of irrigated rice were evaluated for the exudation rate of total organic carbon (EXRToc), shoot dry matter (SDM), and physiological variables related to photosynthesis during the full flowering (blooming) period. Two experiments were...
Tipo: Info:eu-repo/semantics/article
Palavras-chave: Oryza sativa; Photosynthesis; Exudates; Methanogenesis.
Ano: 2018
URL: http://www.scielo.br/scielo.php?script=sci_arttext&pid=S0103-84782018001200250