Surfactants protect the activities of endoglucanase and cellobiohydrolase from gas-liquid interface

Abstract

The reasons for nonionic surfactants mitigated the cellulase deactivation were investigated from the points of lignocellulose-cellulase interaction and gas-liquid interface-cellulase interaction. Surfactants strengthened the interaction between substrate and cellulase, increasing the adsorption capacity by 19.0 %–45.8 % and glucose yield by 15.4 %–17.0 % respectively. Gas-liquid interface had a negative effect on the enzymatic hydrolysis with low enzyme loading at high shaking speed or large interfacial size. The enhancement in glucose yield by surfactants at 250 rpm or large interfacial size was greater than that at 0−150 rpm or small interfacial size. When cellulase solution was incubated at 250 rpm and large interface, the addition of Tween 80 increased the endoglucanase and cellobiohydrolase activities from 76.7 % and 63.0 % to 103.1 % and 123.2 %, respectively. Surfactants protected the endoglucanase and cellobiohydrolase from gas-liquid interface to enhance the enzymatic hydrolysis of hydrogen peroxide/acetic acid-pretreated poplar.