Effect of physical and chemical pretreatment methods on sawdust for improved saccharification

摘要

Sawdust from sawmills being invaluable substrate possess high potential for the production of bioethanol due to many deep rooted benefits. Production of bioethanol by enzymatic hydrolysis of lignocellulosic biomass imply many steps including pretreatment, saccharification and fermentation but pretreatment is the most crucial step as structural hindrances are to be removed first for cellulases to act on lignocellulosic substrates. In the present study different pretreating agents i.e. Autohydrolysis, hydrogen peroxide, microwaves and urea: thiourea are assessed for lignin removal from saw dust. Among these, maximum delignification of 32.96% was observed using urea: thiourea in a proportion of 1:4. Furthermore, best pretreated samples of each strategy were further analyzed for saccharification using hyperthermophilic cellulases under similar conditions. Among all, urea:thiourea pretreated sample of sawdust showed maximum saccharification i.e. 37.38% as compared to control sample for which 14.56% saccharification was recorded. This pretreatment resulted in 2.56 fold increase in the saccharification of saw dust.