부산대학교 도서관

High-rate production of methane from acetate using a fixed-bed reactor filled with marine sediment containing halotolerant aceticlastic methanogens and 3 % NaCl was investigated. In continuous culture, the methane production rate increased with increasing dilution rate. The maximum methane production rate of 750 mM d−1 was observed at a dilution rate of 16.2 d−1, which is impossible without immobilization of the cells in the sediment. Using scanning electron microscopy, we observed Methanosaeta-like filamentous microorganisms and Methanosarcina-like coccoid microorganisms in granule-like structures. The results demonstrated that marine sediment is not only a promising microbial resource of halophilic aceticlastic methanogens, but also a supporting material to fix aceticlastic methanogens in a fixed-bed reactor.