Application of Clostridium thiosulphatireducens, Enterobacter aerogenes and their co-culture inoculum for Biohydrogen Production

Abstract

Abstract Biohydrogen has drawn the attention of researchers all over the world due to its advantages over conventional fuels. However, it is necessary to make the process of biohydrogen production economically and environmentally sustainable. In this study, biohydrogen production from soybean straw in anaerobic batch reactor (sera bottles) using H2 producing bacteria (Clostridium thiosulphatireducens and Enterobacter aerogenes) was investigated. Candidate strains were identified and analyzed by phylogenetic analysis. These bacteria were tested for their biohydrogen production singly as well as in combination. C. thiosulphatireducens, E. aerogenes and their co-culture inoculums were named as strain I, strain II and co-culture inoculum respectively. The fermentation process was carried out at 37°C at pH 6. Physico-chemical characteristics of substrate, cellulase enzyme activity, and 16S rDNA gene sequences were investigated. Maximum cellulase production was observed in co-culture inoculum which was 4.004 IU/ml. Maximum biohydrogen yield obtained was 1.39 mol of H2/g TS. By products formed during fermentation were acetic, butyric and propionic acid and formic acid. The analysis of variance (ANOVA) R2 value 0.843 indicates that 84.3% of variation in production of mol of H2 is explained by its relationship with microbial culture.