Monday, April 29, 2013
Exhibit Hall
Extractive-Ammonia (EA) is a novel process developed at Michigan State University for pretreatment of lignocellulosic biomass. During EA pretreatment, close to 50% of total lignin can be extracted from the biomass while converting the native cellulose I allomorph to its cellulose III form. These physicochemical modifications within the biomass have been shown to increase the overall enzymatic digestion rate several folds (Chundawat et al., 2011. JACS 133, 11163-11174) compared to conventional AFEX pretreated biomass (i.e., without any extractives removal or cellulose III formation). The goal of this project is to optimize mixtures of enzymes (cellulases and hemicellulases made available through the GLBRC) to maximize the hydrolysis of EA pretreated corn stover and compare results to a previous report on AFEX-pretreated corn stover (Gao D et. al., 2010, Biores Technol. 101:2770-81). Through this study, we aim to understand the impact of EA pretreatment conditions on hydrolytic enzymes catalytic efficiency and their stability during the course of biomass saccharification. The core components of the enzyme mixture were purified from various fungal sources and are comprised of Cellobiohydrolase I (CBH I), Cellobiohydrolase II (CBH II), Endoglucanase I (EG I), and Endoxylanase (EX), β-Glucosidase (βG), β-xylosidase (βX), α-Glucoronidase (aGlc), α-L-Arabinofuraosidase (aArf), Cel61A, Endoglucanase II (Cel5A, EGII), and Endoxylanase 2 (EX2). Synergistic interactions between these enzymes were studied using a statistically driven approach using a high throughput micro plate based hydrolysis platform.