Tween-80 (polysorbate 80) is a nonionic surfactant and emulsifier derived from polyethoxylated sorbitan and oleic acid, and is often used in foods. Many papers have been published to study its effect on enzymatic hydrolysis. According to the results, Tween additives increased hydrolysis efficiency of lignocelluloses, but its effect on hydrolysis of pure cellulose was unclear. The exact factors that influenced surfactants effect and mechanism of Tweens effect on pure cellulose hydrolysis were investigated by researchers in Institute of Process Engineering, Chinese Academy of Sciences.
With different shaking speed, Tween-80 showed different effects on hydrolysis of pure cellulose. It was demonstrated that cellulose conversion improved greatly by Tween-80 at a high shaking speed to 180rpm. To study the mechanism of the effect, they focused on three aspects: protecting free cellulase from deactivation, decreasing cellulase proteins adsorption and reducing the cellulase deactivation during the interaction between enzyme and substrate.
Tween-80 did not show any positive effects in the first nor second experimental conditions. However, under the condition of reducing the cellulose deactivation, with the changes of enzyme relative activities in the supernatant, Tween-80 showed positive effect and greatly improved the relative activities of endoglucanase and exoglucanase. And the results demonstrated that Tween-80 improved the cellulose conversion because of the reduction of the adsorbed cellulose deactivationduring the interaction between enzyme and substrate.
Financial assistance was provided by Knowledge Innovation Program of Chinese Academy of Sciences (Grant No.KSCX1-YW-11A2). The results of this work were published onBiochemical Engineering Journal.