it was found that the sugar consumption was 25 g/l and the remaining sugar in the system was 4.6 g/l after 96 h of fermentation time. It should be noted that, hydrolysis of pretreated OPEFB produced 41% of glucose, 26% of xylose, 9% of arabinose and the remaining were galactose and mannose, reported as in a previous experiment [7].