Effect of some factors on biohydrogen production capacity of bacterium Clostridium sp. tr2 from molasses by micro-aerobic fermentation
Keywords:biohydrogen, hydrogen producing bacteria, dark fermentation, micro-aerobic, molasses.
In Vietnam, sugar industry is strongly developed. In this industry, sugar output not only satisfy domestic demand but also for the export and a large amount of molasses was not effectively used. Molasses containing the mixture of sugar and a little amount of vitamins and minerals could be used as materials for other industries. Biohydrogen production from molasses is regarded as a new, potential way to produce a clean, renewable energy with suitable price in order to satisfy the energy demand as well as to solve environmental pollution. In this paper, we studied the biohydrogen production from molasses by bacterium Clostridium Tr2 isolated from buffalo-dung in Vietnam using micro-aerobic fermentation. Various medium components (inoculum size, carbon and nitrogen sources, iron, sodium) and environmental factors (initial medium pH and temperature) were evaluated for their effects on the growth and the hydrogen production capacity by Clostridium sp. Tr2. Obtained results showed that the most suitable conditions for the growth and hydrogen production of strain Tr2 in dark, micro-aerobic fermentation consist of 10% (v/v) pre-culture, 15 ml/l molasses, 3 g/l yeast extract, 100 mg/l FeSO4.7H2O, initial medium pH 6.5, 30oC.