Reducción de metano in vitro con el glucósido cianogénico Linamarina / Reduction of in vitro methane with the cyanogenic glucoside Linamarin

RESUMEN Objetivo. Evaluar el efecto de dosis crecientes del glucósido cianogénico Linamarina, en la reducción de metano ruminal in vitro. Materiales y Métodos. Se empleó líquido ruminal de dos ovejas fistuladas de la raza Merino Precoz, con el que se inoculó un sustrato fermentativo constituido por heno de alfalfa (Medicago sativa) y grano de avena molido (Avena sativa L.), se adicionó solución buffer y Linamarina (pureza de ≥98%) en dosis crecientes, lo que se llevó a incubación por ocho horas in vitro. El metano se midió cada hora, con un monitor de gases infrarrojo. Resultados. De acuerdo con el incremento de las dosis de Linamarina (0, 6, 13, 20 y 26 mg/L), la concentración de metano disminuyó de forma lineal (p≤0.05) en (9.7, 9.2, 18.1 y 29.4%) respectivamente. Se observó una reducción significativa de metano con la dosis más alta de Linamarina. Conclusión. La Linamarina, en su estado puro, fue eficaz en la reducción de metano durante la fermentación ruminal in vitro. Por lo tanto, este estudio constituye una base para futuros experimentos que incluyan fuentes vegetales de Linamarina y otras variables ruminales, lo que puede conducir a encontrar estrategias para reducir los gases de efecto invernadero.

ABSTRACT Objective. To assess the effect of rising doses of the cyanogenic glucoside Linamarin on the reduction of in vitro rumen methane. Materials and methods. Rumen fluid from two fistulated Merino Precoz sheep, inoculated with a fermentation substrate comprising alfalfa hay (Medicago sativa) and ground oat grain (Avena sativa L.), and added with buffer solution and Linamarin (purity ≥98%) in rising doses, was incubated for eight hours in vitro. Methane was measured each hour with an infrared gas monitor. Results. According Linamarin doses were increased (0, 6, 13, 20 and 26 mg/L), the methane concentration fell in a linear manner (p≤0.05) by (9.7, 9.2, 18.1 and 29.4%), respectively. A significant reduction of methane was seen whit the highest dose of Linamarin. Conclusions. Linamarin, in pure state, was effective to reduce methane during in vitro ruminal fermentation. Therefore, this study constitutes a basis for future experiments including vegetable sources of Linamarin as well as other rumen variables, leading to find a strategy for reducing greenhouse gases.

Insights into the microbial community structure of anaerobic digestion of municipal solid waste landfill leachate for methane production by adaptive thermophilic granular sludge

BACKGROUND: The amount of municipal solid waste (MSW) gradually increased along with the rapid development of modern cities. A large amount of landfill leachate are generated with excessive chemical oxygen demand (COD), which create a great deal of pressure on the environment-friendly treatment process. Anaerobic digestion is an ideal technique to solve the above problem. RESULTS: A thermophilic granular sludge was successfully adapted for anaerobic digestion of MSW leachate (from an aging large-scale landfill) for methane production. The COD degradation efficiency improved by 81.8%, while the methane production rate reached 117.3 mL CH4/(g VS d), which was 2.34-fold more than the control condition. The bacterial and archaeal communities involved in the process were revealed by 16S rRNA gene high-throughput pyrosequencing. The richness of the bacterial community decreased in the process of thermophilic granular sludge, while the archaeal community structure presented a reverse phenomenon. The bacterial genus, Methanosaeta was the most abundant during the mesophilic process, while Methanobacterium, Methanoculleus, Methanosaeta and Methanosarcina were more evenly distributed. The more balanced community distribution between hydrogenotrophic and acetotrophic methanogens implied a closer interaction between the microbes, which further contributed to higher methane productivity. The detailed relationship between the key functional communities and anaerobic digestion performances were demonstrated via the multivariate canonical correspondence analysis. Conclusions: With the assistance of adaptive thermophilic granular sludge, microbial community structure was more evenly distributed, while both of COD degradation rate and methane production was improved during anaerobic digestion of MSW landfill leachate.

Effects of volatile fatty acids in biohydrogen effluent on biohythane production from palm oil mill effluent under thermophilic condition

Background: Biohydrogen effluent contains a high concentration of volatile fatty acid (VFA) mainly as butyric, acetic, lactic and propionic acids. The presence of various VFAs (mixture VFAs) and their cooperative effects on two-stage biohythane production need to be further studied. The effect of VFA concentrations in biohydrogen effluent of palm oil mill effluent (POME) on methane yield in methane stage of biohythane production was investigated. Results: The methane yield obtained in low VFA loading (0.9 and 1.8 g/L) was 15­20% times greater than that of high VFA loading (3.6 and 4.7 g/L). Butyric acid at high concentrations (8 g/L) has the individual significantly negative effect the methane production process (P b 0.05). Lactic, acetic and butyric acid mixed with propionic acid at a concentration higher than 0.5 g/L has an interaction significantly negative effect on the methanogenesis process (P b 0.05). Inhibition condition had a negative effect on both bacteria and archaea with inhibited on Geobacillus sp., Thermoanaerobacterium thermosaccharolyticum, Methanoculleus thermophilus and Methanothermobacter delfuvii resulting in low methane yield. Conclusion: Preventing the high concentration of butyric acid, and propionic acid in the hydrogenic effluent could enhance methane production in two-stage anaerobic digestion for biohythane production.

Effects of essence oil additives added to different feeds on methane production / Efectos sobre la producción de metano de los aceites esencias añadiendo diferentes aditivos

ABSTRACT Objective. The aim of the study is to determine the effect of different plant essence oil supplementation to TMR, concentrate and hay on methanogenesis and at 2, 8 and 24 hours (h) using in vitro gas production technique in cattle. Material and methods. Three fistulated Holstein dairy cows were used for rumen fluid collection for application of in vitro gas production technique. Four essence oils (T. vulgaris, O. vulgare, S. aromaticum, Z. officinale) were used as plant extracts. Results. Essence oil supplementation, particularly at increased doses, significantly decreased methane production for TMR, concentrate and hay at 8 and 24 h compared to negative and positive control groups (p<0.05). Among all plant extracts, Syzygium 200 ppm supplementation resulted the lowest methane production values (p<0.05). While methane production at 24 h in positive control groups were recorded respectively as 10.45, 10.75 and 10.07 for TMR, concentrate and hay, the values in Syzygium 200 ppm group were recorded respectively as 1.65, 3.28 and 1.98 for these feed groups. Conclusions. The findings of the study indicate that increased doses of essence oil supplementation significantly decrease methane production in ruminants. Hence, it is suggested that essence oil will be highly beneficial in ruminant nutrition.

RESUMEN Objectivo. El objectivo del presente estudio es determin que el efecto de diferentes suplementos de aceite de esencia de la planta es de TMR, concentrado y heno en la metanogénesis ya los 2, 8 y 24 horas (h) utilizando la técnica in vitro de producciόn de gas en los bovinos. Material y métodos. Tres vacas lecheras Holstein fistulados se utilizaron para la acumulación de líquido ruminal para la aplicación de la técnica in vitro de producción de gas en. Cuatro aceites esenciales (T.vulgaris, O.vulgare, S.aromaticum, Z.officinale) fueron utilizadas como extractos de plantas. Resultados. La administración de suplementos de aceite de esencia, particularmente a elevadas dosis, disminoyó significativamente la producción de metano de TMR, se concentran y heno a las 8 y las 24 h en comparación con los grupos negativos y positivos de control (p<0.05). Entre todos los extractos de plantas, Syzgium 200 suplementación ppm de corrientes de aire los valores de producción de metano màs bajas (p<0.05). Mientras que la producción de metano a las 24 h en los grupos de control positivos, respectivamente, como 10.45, 10.75 y 10.07 am para TMR, concentrarse y heno, los valores de Syzygium grupo de 200 ppm se registraron, respectivamente 1.65, 3.28 y 1.98 para los thes grupos alimentar. Conclusiones. Los resultados del estudio indican que las dosis elevadas de suplementos de aceite de esencia para disminuir significativamanente la producción de metano en rumiantes. Por lo tanto, se sugiere que el aceite de esencia será altamente beneficioso en la nutrición de rumiantes.

Effects of Kikuyu grass (Pennisetum clandestinum) age and different forage: concentrate ratios on methanogenesis / Efecto de la edad del pasto kikuyo (Pennisetum clandestinum) y la relación forraje: concentrado sobre la metanogénesis

Objective. To evaluate the effect of Kikuyu grass (Pennisetum clandestinum) harvested at two different ages and three forage: concentrate supplement ratios (F/C) on methane (CH4) production, dry matter digestibility (DMD), and fermentation profile using the in vitro gas production technique. Materials and methods. six treatments, resulting from the combination of pasture age (30 or 60 days) and F/C (100/0, 75/25, or 50/50) were evaluated using a 2x3 factorial design. The response variables were measured 6, 12, 24 and 48 hours after incubation. A repeated-measure over time design was used to analyze the data, and differences between means were determined with the LSMEANS procedure of SAS. Results. the youngest grass (30 days) was more digestible, produced less CH4 per gram of digestible dry matter (dDM) and more total volatile fatty acids (VFA) compared to the oldest grass (60 days; p <0.05). Reductions of the F/C ratio increased DMD and CH4 production per gram of dDM (p<0.05) but had no significant effect on VFA concentration (p>0.05). Conclusions. under in vitro conditions and pH close to neutrality, the older grass reduces DMD and increases CH4 production per gram of dDM, while a F/C reduction increases DMD and CH4 production per gram of dDM, which differs with reports conducted in vivo.

Objetivo. Evaluar el efecto de la edad del pasto kikuyo (Pennisetum clandestinum) y de la relación forraje/suplemento (F/S) sobre la producción de metano (CH4), la digestibilidad de la materia seca (DMS) y el perfil de fermentación mediante la técnica in vitro de producción de gas. Materiales y métodos. Seis tratamientos, resultantes de la combinación de los factores edad del pasto (30 y 60 días) y relación F/S (100/0, 75/25 y 50/50), fueron evaluados bajo un diseño factorial 2x3. Las variables respuesta se midieron a las 6, 12, 24 y 48 horas de incubación. Para el análisis de los datos se empleó un diseño de medidas repetidas en el tiempo y las diferencias entre medias se determinaron con el procedimiento LSMEANS de SAS. Resultados. El pasto de menor edad (30 días) fue más digestible, produjo menos CH4 por gramo de materia seca digestible (MSd) y más ácidos grasos volátiles totales (AGV) que el pasto de mayor edad (60 días, p<0.05). La reducción en la relación F/S aumentó la DMS y la producción de CH4 por gramo de MSd (p<0.05), pero no tuvo efecto estadístico sobre la concentración de AGV (p>0.05). Conclusiones. Bajo condiciones in vitro, con pH próximo a la neutralidad, la mayor edad del pasto reduce la DMS y aumenta la producción de CH4 por gramo de MSd, mientras que la reducción en la relación F/S aumenta la DMS y la producción de CH4 por gramo de MSd, último hallazgo que contrasta con los reportes in vivo.

Effect of Garlic Powder on Methane Production Rumen Fermentation and Milk Production of Buffaloes.

Aims: Use of natural feed additives to improve the milk production of buffalos. Place and Duration of Study: National Dairy Research Institute, Karnal, India between May 2011 and July 2012. Methodology: Garlic Powder (GRP) at 2, 4, and 6% of DMI was incubated for 24h in diluted ruminal fluid with a 50:50 roughage: concentrate wheat straw based diet. GRP at 2 and 6% DMI have resulted in decrease of molar proportion of acetate and butyrate but it has not effected on in vitro true dry matter digestibility and propionate production. Results: Methane emission was significantly (P<0.05) decreased in presence of GRP. Further, GRP (at the rate 2% of DMI) was evaluated under in vivo conditions in Ten lactating Murrah buffaloes divided into two groups i.e. Control and Treatment group , and it shown very promising results on methane reduction. Methane was reduced up to 31% in case of GRP, without affecting digestibility of nutrients and milk composition in comparison to control group. Conclusion: Overall milk production was remained similar in all groups but just after supplementation of GRP, and up to 12 weeks of supplementation, it remained significantly higher in treatment group as compared to control group.

Contributions of available substrates and activities of trophic microbial community to methanogenesis in vegetative and reproductive rice rhizospheric soil.

Potential of methane production and trophic microbial activities at rhizospheric soil during rice cv. Supanburi 1 cultivation were determined by laboratory anaerobic diluents vials. The methane production was higher from rhizospheric than non-rhizospheric soil, with the noticeable peaks during reproductive phase (RP) than vegetative phase (VP). Glucose, ethanol and acetate were the dominant available substrates found in rhizospheric soil during methane production at both phases. The predominance activities of trophic microbial consortium in methanogenesis, namely fermentative bacteria (FB), acetogenic bacteria (AGB), acetate utilizing bacteria (AB) and acetoclastic methanogens (AM) were also determined. At RP, these microbial groups were enhanced in the higher of methane production than VP. This correlates with our finding that methane production was greater at the rhizospheric soil with the noticeable peaks during RP (1,150 ± 60 nmol g dw-1 d-1) compared with VP (510 ± 30 nmol g dw-1 d-1). The high number of AM showed the abundant (1.1x104 cell g dw-1) with its high activity at RP, compared to the less activity with AM number at VP (9.8x102 cell g dw-1). Levels of AM are low in the total microbial population, being less than 1% of AB. These evidences revealed that the microbial consortium of these two phases were different.