Anaerobic rumen SBR for degradation of cellulosic material

Abstract

Hydrolysis of organic particulates under anaerobic conditions is generally regarded as the rate limiting step in solid digestion processes. Rumen-based ecosystems appear to achieve very high hydrolysis rates for cellulosic organic material. This study aimed at the development and demonstration of an anaerobic sequencing batch reactor (SBR) process operating with a rumen-based microbial inoculum. Fibrous alpha cellulose was used as sole carbon substrate and the use of an SBR operating cycle allowed the utilisation of a high liquid flow rate (hydraulic retention time of 0.67 d) while maintaining a much longer solids retention time of 7 d. Complete mass balances for carbon and nitrogen, as well as COD balancing allowed the full characterisation of the process stoichiometry and kinetics. Elemental analysis of the biomass revealed a composition of C5H4.8O2.4N0.7, which is quite different from other generic biomass compositions used in the literature. The anaerobic rumen SBR was compared with another rumen-based reactor system in the literature which used a continuous filtration process for solid/liquid separation. This comparison showed that the volatile fatty acid production rate from cellulose in the anaerobic SBR was comparable with the performance achieved in the continuous system, although loading, substrate type and media composition were quite different between these two studies. Further evaluation of the anaerobic rumen SBR is required to determine its practical application for other substrates and to demonstrate the scale-up potential of this concept.

Intake and Digestibility of Cattle’s Ration on Complete Feed Based-On Fermented Ammonization Rice Straw with Different Protein Level

“…This has attracted increasing interests among the researchers worldwide. Rumen microorganism have been successfully employed to digest a variety of lignocellulosic biomass, including agricultural residues, organic fraction of the municipal solid wastes and aquatic plants (Van Soest, 1994; Barnes and Keller, 2004;Hu and Yu, 2005;Van Soest, 2006;Yue et al, 2007;Yue et al, 2013).…”

Metagenomic insights into the rumen microbial fibrolytic enzymes in Indian crossbred cattle fed finger millet straw

“…Microbes belonging to both genera Bacteroides and Prevotella were found to possess a large repertoire of CAZymes; Bacteroides were the chief manufacturers of CAZyme class GTs, whereas Prevotella were the principal contributors of GHs in cattle rumen. The natural capability of rumen microbiota to produce an array of potential enzymes that hydrolyze the rigid lignocellulose biomass has been successfully employed to treat different systems like agricultural residues and straw waste (Hu et al 2007; Barnes and Keller 2004). The application of different artificial rumen systems for organic waste conversion (Yue et al 2013) was also being extensively studied.…”

Organic acid production from potato starch waste fermentation by rumen microbial communities from Dutch and Thai dairy cows

“…Rumen fluid has been used as an inoculum in biotechnological processes to improve municipal solid waste treatment in anaerobic digestion [ 15 ] and to increase hydrolysis of cellulosic organic material [ 16 , 17 ]. Using a rumen-derived inoculum, which harbours high microbial hydrolytic activities, could reduce the pre-treatment costs in anaerobic digestion since there is little or no requirement to add hydrolytic enzymes [ 18 ].…”