Bioethanol production from four abundant Indian agricultural wastes

Lignocellulose feedstocks are promising second-generation sources of ethanol biofuel. They include massive amounts of agricultural waste generated in India, much of which is currently burnt (exacerbating major pollution problems), but could potentially be fermented. To assist efforts to realize this potential, four abundant kinds of Indian agricultural residues (sugarcane bagasse and straw from rice, sweet sorghum and millet) were hydrolyzed via a dilute-acid method and fermented at 27 degrees C, using the white-rot fungusTrametes versicoloras a biocatalyst. The total carbohydrate contents of the agriculture wastes were analyzed, as well as soluble sugar contents of the hydrolysates at the start and end of the fermentations; their ethanol yields and activities of the key enzymes aldehyde dehydrogenase and pyruvate decarboxylase were also measured. Results show that ca. 85-90% of the fermentable sugars were used for ethanol production, and the enzyme activities are consistent with the observed yields. The findings indicate a great potential for ethanol production from Indian agricultural waste.