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Methane production

Xuan Zhou, Marc J A Stevens, Stefan Neuenschwander, Angela Schwarm, Michael Kreuzer, Anna Bratus-Neuenschwander, Johanna O Zeitz
OBJECTIVE: Lauric acid (C12 ) is a medium-chain fatty acid that inhibits growth and production of the greenhouse gas methane by rumen methanogens such as Methanobrevibacter ruminantium. To understand the inhibitory mechanism of C12 , a transcriptome analysis was performed in M. ruminantium strain M1 (DSM 1093) using RNA-Seq. RESULTS: Pure cell cultures in the exponential growth phase were treated with 0.4 mg/ml C12 , dissolved in dimethyl sulfoxide (DMSO), for 1 h and transcriptomic changes were compared to DMSO-only treated cells (final DMSO concentration 0...
February 17, 2018: BMC Research Notes
Mutian Niu, Ermias Kebreab, Alexander N Hristov, Joonpyo Oh, Claudia Arndt, André Bannink, Ali R Bayat, André F Brito, Tommy Boland, David Casper, Les A Crompton, Jan Dijkstra, Maguy A Eugène, Phil C Garnsworthy, Md Najmul Haque, Anne L F Hellwing, Pekka Huhtanen, Michael Kreuzer, Bjoern Kuhla, Peter Lund, Jørgen Madsen, Cécile Martin, Shelby C McClelland, Mark McGee, Peter J Moate, Stefan Muetzel, Camila Muñoz, Padraig O'Kiely, Nico Peiren, Christopher K Reynolds, Angela Schwarm, Kevin J Shingfield, Tonje M Storlien, Martin R Weisbjerg, David R Yáñez-Ruiz, Zhongtang Yu
Enteric methane (CH 4 ) production from cattle contributes to global greenhouse gas emissions. Measurement of enteric CH 4 is complex, expensive and impractical at large scales; therefore, models are commonly used to predict CH 4 production. However, building robust prediction models requires extensive data from animals under different management systems worldwide. The objectives of this study were to (1) collate a global database of enteric CH 4 production from individual lactating dairy cattle; (2) determine the availability of key variables for predicting enteric CH 4 production (g/d per cow), yield [g/kg dry matter intake (DMI)], and intensity (g/kg energy corrected milk) and their respective relationships; (3) develop intercontinental and regional models and cross-validate their performance; and (4) assess the trade-off between availability of on-farm inputs and CH 4 prediction accuracy...
February 16, 2018: Global Change Biology
Anongnart Wannapokin, Rameshprabu Ramaraj, Kanda Whangchai, Yuwalee Unpaprom
Biogas production from anaerobic co-digestion of fallen teak leaves ( Tectona grandis ) and microalgae ( Chlorella vulgaris ) were investigated. In this study, teak leaves and algae mixtures with or without pretreatment were used as the substrates and digested in 1-L of anaerobic fermenter, then optimal conditions were performed in 6-L fermenter. Pretreatment was performed using sodium hydroxide (NaOH) solution (w/v) at different conditions (0, 2, 3 and 4%), with different total solid (TS) ratios (10, 15 and 20%)...
February 2018: 3 Biotech
Zongjun Li, Nannan Liu, Yangchun Cao, Chunjia Jin, Fei Li, Chuanjiang Cai, Junhu Yao
Background: In rumen fermentation, fumaric acid (FA) could competitively utilize hydrogen with methanogenesis to enhance propionate production and suppress methane emission, but both effects were diet-dependent. This study aimed to explore the effects of FA supplementation on methanogenesis and rumen fermentation in goats fed diets varying in forage and concentrate particle size. Methods: Four rumen-cannulated goats were used in a 4 × 4 Latin square design with a 2 × 2 factorial arrangement of treatments: low or high ratio of forage particle size: concentrate particle size (Fps:Cps), without or with FA supplementation (24 g/d)...
2018: Journal of Animal Science and Biotechnology
Keum-Joo Park, Seong-Gyu Seo, Eun-Sik Kim, M N Islam, Hyung-Woon Song, Hyung-Sun Yoon
In this study, the nano-sized fume biogas production from food waste was investigated using lab scale semi-continuous stirred tank reactor (SCSTR) at 35 °C with 30d HRT and 30L working volume. The mesophilic digestion test was performed with three different feed materials (food waste) and food to microorganism (F/M) ratios (0.13, 0.34, and 0.27) in the same experiment. The results showed that the F/M ratios significantly affected the biogas production rate. The highest production rate was obtained at F/M ratio of 0...
February 1, 2018: Journal of Nanoscience and Nanotechnology
Emily K Stern, Darren M Brenner
Irritable bowel syndrome (IBS) is a common, heterogeneous disorder characterized by abdominal pain associated with changes in bowel habits. The pathogenesis of IBS is multifactorial and may relate to alterations in the gut microbiota, changes in visceral sensation and motility, and genetic and environmental factors. Administration of systemic antibiotics may increase the risk of IBS by altering gastrointestinal homeostasis. Therapeutic interventions for IBS with diarrhea that are thought to target alterations in the gut microbiota include the nonsystemic antibiotic rifaximin, the medical food serum-derived bovine immunoglobulin, prebiotics, probiotics, and dietary modification...
February 15, 2018: Clinical and Translational Gastroenterology
Zhengsheng Yu, Xiaoyun Leng, Shuai Zhao, Jing Ji, Tuoyu Zhou, Aman Khan, Apurva Kakde, Pu Liu, Xiangkai Li
Anaerobic digestion (AD) has been widely used for biogas or biofuel generation from waste treatment. Because a low production rate and instability of AD occur frequently, various technologies have been applied to improvement of AD. Microbial electrolysis cells (MECs), an emerging technology, can convert organic matter into hydrogen, methane, and other value-added products. Recent studies showed that application of MEC to AD (MEC-AD) can accelerate degradation of a substrate (including recalcitrant compounds) and alter AD microbial community by enriching exoelectrogens and methanogens thus increasing biogas production...
February 12, 2018: Bioresource Technology
Bo Fu, Tao Jiang, Yan Zhu
We report an interesting structural effect of one-dimensional Sm2O3 catalysts such as nanorods, nanobelts and nanotubes synthesized by a simple solvothermal method on oxidative coupling of methane. The Sm2O3 nanobelts showed the 28% CH4 conversion and 42% C2 selectivity at 500 °C. The different spatial structures and surface structures of these Sm2O3 catalysts indeed brought about the distinct exposed facets, surface active oxygen species and surface active sites, which could account for their diverse activity and products selectivity in OCM reaction...
May 1, 2018: Journal of Nanoscience and Nanotechnology
Buddhadeb Ghosh
Three ground-based ambient air studies were conducted in February through March of 2015, 2016, and 2017 at the Phillips 66 Research Center in Northeastern Oklahoma. C2-C12 non-methane hydrocarbons (NMHCs) were measured using whole air sampling/gas chromatography-mass spectrometry. In 2016 and 2017, online methane and ethane measurements were also conducted. Strong methane-ethane correlation identified oil & gas (O&G) upstream/midstream operations to be the primary methane source. C2-C5 alkanes were the dominant NMHCs whose average mixing ratio peaked in 2016 before dropping in 2017...
February 13, 2018: Environmental Science & Technology
Kyungjin Cho, Yeongmi Jeong, Kyu Won Seo, Seockheon Lee, Adam L Smith, Seung Gu Shin, Si-Kyung Cho, Chanhyuk Park
An anaerobic ceramic membrane bioreactor (AnCMBR) has been attracted as an alternative technology to co-manage various organic substrates. This AnCMBR study investigated process performance and microbial community structure at decreasing temperatures to evaluate the potential of AnCMBR treatment for co-managing domestic wastewater (DWW) and food waste-recycling wastewater (FRW). As a result, the water flux (≥6.9 LMH) and organic removal efficiency (≥98.0%) were maintained above 25 °C. The trend of methane production in the AnCMBR was similar except for at 15 °C...
February 7, 2018: Bioresource Technology
Jibao Liu, Min Yang, Junya Zhang, Jiaxi Zheng, Hui Xu, Yawei Wang, Yuansong Wei
This study gave a comprehensive insight into the effects of microwave-H2O2 pretreatment on concentrated sludge anaerobic digestion (AD). Results showed that mixture of activated sludge and pretreated sludge at mass ratio of 1:1 was efficient for enhancing AD, methane production was increased from 215.51 mL/g VSadded to 258.38 mL/g VSadded. Pretreatment resulted in the change of sludge properties, such as solubilization of organic matters, decrease of viscosity. For concentrated sludge AD, the "pH buffer system" ensured the "inhibitory steady state" during start-up period, and significant archaeal community shift from Methanosaeta to Methanosarcina ensured the true steady-state operation...
February 1, 2018: Bioresource Technology
Fábio Codignole Luz, Maurizio Volpe, Luca Fiori, Alessandro Manni, Stefano Cordiner, Vincenzo Mulone, Vittorio Rocco
This study reports the implications of using spent coffee hydrochar as substrate for anaerobic digestion (AD) processes. Three different spent coffee hydrochars produced at 180, 220 and 250 °C, 1 h residence time, were investigated for their biomethane potential in AD process inoculated with cow manure. Spent coffee hydrochars were characterized in terms of ultimate, proximate and higher heating value (HHV), and their theoretical bio-methane yield evaluated using Boyle-Buswell equation and compared to the experimental values...
February 7, 2018: Bioresource Technology
Jo De Vrieze, Michiel De Waele, Pascal Boeckx, Nico Boon
Process monitoring of anaerobic digestion is typically based on operational parameters, such as pH and volatile fatty acid concentration, that are lagging on actual microbial community performance. In this study, 13C isotope fractionation in CH4 and CO2 in the biogas was used to monitor process stability of anaerobic digestion in response to salt stress. A gradual and pulsed increase in salt concentration resulted in a decrease in methane production. No clear shift in δ13CH4 was observed in response to the gradual increase in salt concentration, and δ13CO2 of the biogas showed only a clear shift after process failure, compared with the control...
February 12, 2018: Environmental Science & Technology
Sasha D Hafner, Johan T Madsen, Johanna M Pedersen, Charlotte Rennuit
Combining aerobic and anaerobic digestion in a two-stage system can improve the degradation of wastewater sludge over the use of either technology alone. But use of aerobic digestion as a pre-treatment before anaerobic digestion generally reduces methane production due to loss of substrate through oxidation. An inter-stage configuration may avoid this reduction in methane production. Here, we evaluated the use of thermophilic aerobic digestion (TAD) as an inter-stage treatment for wastewater sludge using laboratory-scale semi-continuous reactors...
February 2018: Water Science and Technology: a Journal of the International Association on Water Pollution Research
Martijn Diender, Philipp S Uhl, Johannes H Bitter, Alfons J M Stams, Diana Z Sousa
Carbon monoxide-fermenting microorganisms can be used for the production of a wide range of commodity chemicals and fuels from syngas (generated by gasification of, e.g., wastes or biomass) or industrial off-gases (e.g., from steel industry). Microorganisms are normally more resistant to contaminants in the gas (e.g., hydrogen sulfide) than chemical catalysts, less expensive and self-regenerating. However, some carboxydotrophs are sensitive to high concentrations of CO, resulting in low growth rates and productivities...
February 5, 2018: ACS Sustainable Chemistry & Engineering
Juejie Yang, Guanghe Li, Yi Qian, Yunfeng Yang, Fang Zhang
Linking microbial community structure to physiology and ecological processes is a critical focus of microbial ecology. To understand the microbial functional gene patterns related to soil greenhouse gas [carbon dioxide (CO2), methane (CH4) and nitrous oxide (N2O)] emissions under oil contamination, we used functional gene array (GeoChip 5.0) analysis and network methods to investigate the feedback responses of soil microbial functional gene patterns and identify keystone genes in Shengli Oilfield, China. The microbial functional gene number, relative abundance and diversity involved in carbon degradation and nitrogen cycling decreased consistently with the reduced CO2 and N2O flux in oil contaminated soils, whereas the gene number and relative abundance of methane-production related genes increased with contamination...
February 8, 2018: Science of the Total Environment
E Humer, S Aditya, A Kaltenegger, F Klevenhusen, R M Petri, Q Zebeli
A new segment of feed industry based on bakery by-products (BBP) has emerged. Yet, information is lacking regarding the effects of inclusion of BBP in ruminant diets on ruminal fermentation and microbiota. Therefore, the aim of this study was to evaluate the effect of the gradual replacement of grains by BBP on ruminal fermentation, nutrient degradation, and microbial community composition using the rumen-simulation technique. All diets consisted of hay and concentrate mixture with a ratio of 42:58 (dry matter basis), but differed in the concentrate composition with either 45% cereal grains or BBP, whereby 15, 30, or 45% of BBP were used in place of cereal grains...
February 7, 2018: Journal of Dairy Science
Muzammil Anjum, Rajeev Kumar, M A Barakat
Visible light photocatalysts of Cr2O3/C3N4 composites (with different melamine concentrations) were prepared by high temperature calcination method. The composites samples were characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD), scanning electron microscopy SEM, energy-dispersive X-ray spectroscopy (EDX), UV-visible spectroscopy and particle size analysis, which clearly indicated the coexistence of both Cr2O3 and C3N4 in the composites. The Cr2O3/C3N4 catalysts were tested for photocatalytic degradation of 2-chlorophenol in wastewater and solubilization of sludge in anaerobic digestion process to enhance biomethane production...
February 8, 2018: Journal of Environmental Management
Congcong Zhang, Lanmei Zhao, Mutai Bao, Jinren Lu
Potential of hydrolyzed polyacrylamide (HPAM) biodegradation to final products was studied through regulating its own nitrogen transformation. Under the conditions of 2, 3 and 4 mg/L of DO, HPAM removal ratio reached 16.92%, 24.51% and 30.78% and the corresponding removal ratio reached 49.15%, 60.25% and 76.44% after anaerobic biodegradation. NO3--N concentration was 9.43, 14.10 and 17.99 mg/L in aerobic stages and the corresponding concentration was 0.17, 0.07 and 0.008 mg/L after anaerobic biodegradation...
February 2, 2018: Bioresource Technology
Alessandra Fontana, Stefano Campanaro, Laura Treu, Panagiotis G Kougias, Fabrizio Cappa, Lorenzo Morelli, Irini Angelidaki
The present research is the first comprehensive study regarding the thermophilic anaerobic degradation of cheese wastewater, which combines the evaluation of different reactor configurations (i.e. single and two-stage continuous stirred tank reactors) on the process efficiency and the in-depth characterization of the microbial community structure using genome-centric metagenomics. Both reactor configurations showed acidification problems under the tested organic loading rates (OLRs) of 3.6 and 2.4 g COD/L-reactor day and the hydraulic retention time (HRT) of 15 days...
February 7, 2018: Water Research
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