초록
The effect of vitamin B<SUB>12</SUB> on hydrogen (H<SUB>2</SUB>) and 1,3-propanediol (1,3-PD) production in glycerol fermentation of Halanaerobium saccharolyticum subsp. saccharolyticum was studied in batch cultivations. In addition, the effect of vitamin B<SUB>12</SUB> on glucose fermentation of H. saccharolyticum subsp. saccharolyticum and on glycerol fermentation of H. saccharolyticum subsp. senegalensis, that is a non-1,3-PD producing bacterium, and of Clostridium butyricum, that is known for vitamin B<SUB>12</SUB>-independent 1,3-PD production, were studied for comparison. 1,3-PD production of H. saccharolyticum subsp. saccharolyticum was observed to be vitamin B<SUB>12</SUB>-dependent and the H<SUB>2</SUB> production in glycerol fermentation was remarkably enhanced when 1,3-PD production was blocked by the lack of vitamin B<SUB>12</SUB> supplementation. The highest H<SUB>2</SUB> yield obtained by H. saccharolyticum subsp. saccharolyticum was 2.16 mol/mol glycerol. No significant effects of vitamin B<SUB>12</SUB> on metabolite production in glucose fermentation of H. saccharolyticum subsp. saccharolyticum or in glycerol fermentation of H. saccharolyticum subsp. senegalensis or C. butyricum were observed.