초록
Experiments were designed to enumerate variation in biohydrogen (H<SUB>2</SUB>) production pattern with formate and glucose as carbon source under acidogenic mixed microenvironment. High H<SUB>2</SUB> production was observed with glucose (180 ml) when compared to formate (152 ml). The process was validated with modified Gompertz model (R<SUP>2</SUP> = 0.98). Substrate degradation also showed higher removal of glucose (ξ<SUB>COD</SUB>, 82%) compared to formate (ξ<SUB>COD</SUB>, 53%). Nevertheless, specific H<SUB>2</SUB> yield of formate (6.6 mol H<SUB>2</SUB>/kg COD<SUB>R</SUB>) obtained was comparatively higher than glucose (5 mol H<SUB>2</SUB>/kg COD<SUB>R</SUB>). Variation in H<SUB>2</SUB> production was manifested by change in fatty acid composition and substrate degradation pattern. Acetate was obtained as a major metabolic intermediate from the degradation of glucose and a shift in the biochemical pathway towards formation of butyrate occurred after maximum substrate degradation. The role of substrate-dependent dehydrogenase activity was deciphered during H<SUB>2</SUB> production and was evidenced with bio-electrochemical analysis.