Xylanase enhanced second-generation bioethanol production through simultaneous saccharification and fermentation

This study aimed to correlate hydrolytic enzymes with enhanced bioethanol production during the simultaneous process of saccharification and fermentation for different agricultural wastes. This study screened the activities of hydrolytic enzymes to evaluate the simultaneous process and correlated them with bioethanol production. The results of the simultaneous process showed that cantaloupe peels produced the highest amount of reducing sugars and bioethanol. Cellulase showed maximum activity in the first 24 h, indicating that yeast cells favoured glucose over xylose. The results of the simultaneous saccharification and fermentation experiments revealed a 5-fold decrease in cellulase activity after 72 h. Xylanase activity improved from 79.38 to 95.18 U g−1, and bioethanol production was enhanced from 21.42 to 75.66 g L−1, confirming the capability of the simultaneous process to enhance bioethanol production. Although ethanol production was lower than that obtained with xylose cultivation alone, it was higher than that observed with glucose.