Autohydrogenotrophic denitrifying microbial community in a glass beads biofilm reactor

A glass bead biofilm reactor was operated using H2 as an electron donor to remove nitrate at 150 mg NO3-N l(-1) to below detection level. The microbial community in the glass beads biofilm reactor was investigated by using denaturing gradient gel electrophoresis (DGGE) and phylogenetic analysis. In DGGE analysis of the biofilm, five bands were dominant and indicated the presence of eight beta-proteobacteria, one gamma-proteobacteria and twelve clostridia. An unculturable Hydrogenophaga sp., which is a new genus of hydrogen-oxidizing bacterium was dominant in microbial community of the biofilm reactor.