273834 Investigation of Accessory Hemicellulases and Pectinases for Polysaccharide Hydrolysis of Ionic Liquid Pretreated Biomass

Thursday, November 1, 2012: 10:35 AM
303 (Convention Center )
Christopher J. Barr1, Jeffery Mertens2 and Constance Schall1, (1)Chemical and Environmental Engineering, University of Toledo, Toledo, OH, (2)NCAUR, USDA-ARS, Peoria, IL

The polysaccharides, cellulose, hemicellulose, and other additional carbohydrate polymers of terrestrial biomass, comprise renewable feedstocks for carbon-based chemicals and fuels.  Biomass pretreatment is required to overcome its recalcitrance to biochemical deconstruction to monomeric sugars for sugar platform fuels and chemicals.  Ionic liquid (IL) pretreatment followed by enzymatic hydrolysis can be used to saccharify the biomass into its monomeric sugars at a rate much higher than many pretreatment methods.  IL pretreatment creates unique biomass substrates consisting of primarily amorphous cellulose with largely intact hemicellulose and lignin. These substrates differ from many other pretreatments which remove hemicellulose and retain cellulose crystallinity. The unique substrate resulting from IL-pretreatment poses an interesting challenge for enzymatic deconstruction using traditional commercial mixtures.

Enzyme mixtures using A. nidulans mono-component enzymes with accessory hemicellulases and pectinases were formulated and used in hydrolysis experiments.  Exploration of the accessory enzyme requirements yields insight into differences in hemicellulose structure and composition between biomass substrates.  Accessory hemicellulases examined include acetyl xylan esterase (AXE), ferulic acid esterase, and arabinofuranosidase.  In addition to mono-component enzyme mixtures, commercially-available enzyme mixtures were supplemented with accessory enzymes to optimize hydrolysis for lower enzyme loadings.  As part of these studies, analysis of variance (ANOVA) was used to statistically assess and model the main and interaction effects of key enzyme activities.

Extended Abstract: File Not Uploaded