Cellulases can be used in conjunction with yeasts to degrade biomass to ethanol wherein theβ-glucosidase degrades cellobiose to glucose that yeasts can further ferment into ethanol. This production of ethanol from readily available sources of cellulose can provide a stable, renewable fuel source. So simultaneous saccharification and fermentation process(SSF) is regarded as the most effective pathway to convert cellulose to ethanol, in which cellulase is the key factor. However the major rate li...