Effect of green liquor pretreatment on the cellulase production and enzymatic hydrolysis of wheat straw

Green liquor (sodium carbonate and sodium sulifide, GL) pretreated wheat straw was used as carbon source for cellulase production by Trichoderma reesei. The effects of GL pretreatment at different Total Titrateable Alkali(TTA) charge, cooking temperature and sulfidity on pulp yield, cellulase synthesis and yield of enzymatic hydrolysis were investigated. Results indicated that TTA charge was the most important factor which affected the GL pretreatment, followed by sulfidity and cooking temperatures. With TTA charge increasing, the straw pulp yields were declined, but the cellulase activity and the straw yield of enzymatic hydrolysis were increased. When the GL pretreatment condition was 140°C of cooking temperature, 4% of TTA charge and 20% of suldifity, the filter paper activity(FPA), β-glucosidase activity(BGA) and cellulase yield were reached to 3.3 FPIU/mL, 1.1 IU/mL and 93.0 IU/g wheat straw respectively. Studies had shown that it could effectively improve the cellulase activity and enzymatic hydrolysis by using wheat straw after GL pretreatment.