(546c) Production of Butanol and Hydrogen from Agriculture Residues By Using Clostridium Sp. G117

Butanol and hydrogen are recognised as alternative energy to fossil fuels. They can be simultaneously produced during anaerobic fermentation of starchy materials (maize, wheat, millet, rye, etc) and sugars (glucose, xylose and molasses) by using Clostridia. Herein, we report a new isolate Clostridium strain G117 which is able to utilize agricultural residues including rice straw, corn cob, rice bran and sugarcane bagasse in reinforced clostridial medium (RCM) for butanol and hydrogen production. Among the selected substrates, rice bran is found to support high level of butanol (3.48±0.12g/l) and hydrogen (1.98±0.10l/l) production. Rice bran is a good carbon source for culturing strain G117 and butanol production, because it contains a high percentage of hemicellulose (37-40%) and cellulose (27-30%). Because Clostridium also requires nitrogen sources and metal ions for cellular functions and synthesis of biomass, oil cakes from caster, groundnut and sesame were added to culture medium as low-cost nitrogen and mineral sources. Among them, sesame oil cake gives the highest level of butanol (4.71±0.15g/l) and hydrogen (3.73±0.05l/l). Consequently, rice bran (20-60g/l) and sesame oilcake (20-40g/l) were used together to enhance butanol and hydrogen production. Using response surface methodology (RSM), we obtain an optimized medium which contains 48.5g/L of rice bran and 32.8g/L of sesame oilcake. In this medium, 13.7±0.20g/l of butanol and 4.23±0.10l/l of hydrogen can be produced simultaneously. Based on RSM analysis, rice bran has higher impact on butanol and hydrogen production than sesame oilcake. This is the first report dealing with direct fermentation of agriculture residues for butanol and hydrogen production. This bioprocess would be beneficial to industrial-scale production of hydrogen and butanol.