Potency of fibrolytic bacteria isolated from Indonesian sheep's colon as inoculum for biogas and methane production

Abstract

Three fibrolytic bacteria were isolated from sheep’s colon using cellulose (b), xylan (c) and lignin (d) as
\nselective substrates. The potency of fibrolytic was identified by Subbarao methods. These isolates were
\nthen used both in pure and mixed culture with cattle cellulolytic bacteria (a) from the previous research.
\nThe isolates were subsequently selected based on their ability to produce gas through biogas and
\nmethan measurement using in vitro gas test technique of Tilley and Terry methods. Based on the
\nparameter, the potential isolates then were applied as inoculum for dairy cattle feces fermentation. The
\napplication research was based on Randomized Completely Design with inoculum concentration (0, 3, 6
\nand 9%) as the treatment with three replications. The result showed that the highest in vitro biogas and
\nmethane production was obtained from a-c-d co-culture addition. The a-c-d co-culture as inoculum for in
\nvitro feces fermentation could increase gas production 56.36% and methane 18.09% compared to natural
\nfermentation by feces microbes. Application of 3 to 9% of a-c-d inoculum at the fermentation scale was
\nhighly significant (P < 0.01) in increasing biogas production, however, addition of more than 3% of a-c-d
\ninoculum decrease methane concentration. The fibrolytic bacteria from sheep’s colon were potential to
\nincrease the efficiency of biogas and methane production; thus, it should be considered as an inoculum
\nfor anaerobic fiber waste fermentation.