Studies on methanogenic consortia associated with mangrove sediments of Ennore.

In this study, methanogenic consortia were isolated and characterized from eight different sediment samples of mangrove ecosystem located in Ennore, Chennai. Out of eight samples, two consortia (SpR6 and SSS8) were consistent and good at methane production. The maximum methane (6.95%) was produced by the sample collected from the swampy sediments (SSS8) of mangrove environment on 5th day of incubation. The pure colonies of methanogenic consortia (SSS8) isolated in the roll tube produced maximum methane (5%) on 70th day. Further, all the isolated consortia produced methane when it was grown with and without gaseous (H2 and CO2) substrate and the maximum production of 15.1% (SSS8) on 12th day of incubation in the presence of gaseous substrate. Also, the methanogenic consortium isolated from the mangrove environment produced significant amount of methane in tyndallized cow dung (4.7%) than in raw cow dung. The fluorescence of isolated colony and individual cells of methanogenic consortia, methane production, and the amplification of archeal specific 16S rRNA genes confirmed the presence of methanogenic bacteria in the Ennore mangrove sediments.