Shift of microbial community structure by substrate level in dynamic membrane bioreactor for biohydrogen production

Summary The aim of this study was to evaluate the feasibility of biological hydrogen production (BHP) in a dynamic membrane bioreactor. Hydraulic retention time (HRT) was varied from 1 to 12 hours, and the microbial communities were analyzed. The major hydrogen‐producing bacterium was Clostridium chromiireducens, which was enriched up to 82% of the total bacteria with a 2 hour HRT, while Enterobacter cloacae was also observed in the range of 0.2% to 34.4% of total bacteria. When the level of the substrate in the reactor was low (