Tuesday, April 20, 2010
10-16

Understanding possible causes of slow hydrolysis rate through a restart approach

Jian Shi, Mirvat A. Ebrik, and Charles E. Wyman. Center for Environmental Research and Technology Department of Chemical and Environmental Engineering Bourns College of Engineer, University of California at Riverside, 1084 Columbia Avenue, Riverside, CA 92507

The slowing in rate with conversion during enzymatic hydrolysis of cellulosic biomass, especially at low enzyme loadings, leads to low sugar yields and high enzyme costs. Although many plausible causes have been proposed previously, a fundamental question yet to be answered is whether the substrate reactivity and cellulase accessibility to substrate decrease as hydrolysis proceeds. Through cleaning the surface and reintroducing fresh enzyme to partially converted cellulose, “restart” experiments provide a valuable tool to assess the changes in reactivity with minimal alteration to the substrate. In this study, “restart” protocols were coupled with BSA blocking to picture changes in substrate reactivity and understand possible causes of slowing during enzymatic hydrolysis of optimally water-only or dilute acid pretreated hardwood at both low and high enzyme loadings. We then applied the same approaches to evaluate substrate reactivity as a function of pretreatment type and severity. These results provide a better understanding of enzymatic hydrolysis of cellulosic biomass and create new insights toward lower cost processes that support commercialization of cellulosic ethanol technologies.

See more of Poster Session Two
See more of General Submissions

See more of The 32nd Symposium on Biotechnology for Fuels and Chemicals (April 19-22, 2010)