Bioethanol Production by Novel Indigenous Yeast Strains from Lignocellulosic Waste

Abstract

The present study deals with isolation of novel indigenous yeast strains and their use in conversion of lignocellulosic agricultural and household waste into bioethanol. 11 yeast cultures were isolated from different sources and from these four strains of yeast were selected on basis of bioethanol production. Biochemical tests were performed to characterize the isolated yeast cultures. The identification of the unknown yeast strains was then done using the 26S rRNA gene sequence analysis. The yeast cultures were identified as: Pichia farinose, Arxula adeninivorans, Rhodotorula colostri, Stephanoascus ciferrii. These strains were inoculated in fermentation media having lignocellulosic household and agricultural waste in a 3 L fermenter. After 48 h all the four yeast strains converted the lignocellulosic waste to different amounts of bioethanol. Pichia farinose was found to produce a maximum amount of bioethanol, i.e., 31 g/L and Stephanoascus ciferrii produced 28.73 g/L bioethanol when bagasse was used as the carbon source.