Selection and identification of some hydrogen producing bacteria isolated from cattle feces in Vietnam
Keywords:Clostridium, Thermoanaerobacterium, biohydrogen, hydrogen producing bacteria, cattle feces, Vietnam.
Global warming and dwindling fossil fuel supplies have led to a need to develop new, clean and sustainable energy supplies. Amongst, biohydrogen is recognized as a clean, renewable and promising energy alternative for the future since it is efficient and environmentally friendly. There are many possible solutions and a number of these are based on bacteria. Among biological hydrogen production processes, fermentative hydrogen production by strict or facultative anaerobic chemoheterotrophs is a promising method of sustainable hydrogen production. In present paper, four indigenous bacterial strains that are able to produce biohydrogen were studied. All four hydrogen producing bacteria were isolated from cattle feces in Vietnam. Cells of all strain are rod-shaped with different length. Strain Bo 4.1 has flagellum. All strains are Gram posititve bacteria excepting strain Tr2. Among Gram positive strains, only strain Be DA can not make sporulation whereas others Bo 4.1 and Trau DAt can. By combining morphological properties and 16S rRNA analyses, the anaerobic, mesophilic bacteria strain Bo 4.1 and the anaerobic, thermophilic bacterial strain Trau DAt were identified as Clostridium beijerinckii and Thermoanaerobacterium aciditolerans with 99.9%, 99.3% identity, respectively. The other facultative, mesophilic bacterial strains Be DA and Tr2 were characterized as Clostridium sp. basing on morphological properties, API standard kits and 16S rRNA analyses.