title: Optimization of AFEX™ pretreatment conditions and enzyme mixtures to maximize sugar release from upland and lowland switchgrass.
abstract: Switchgrass is a North American grass that is considered to be a highly promising herbaceous bioenergy feedstock. Differences in processing conditions and yields specifically related to switchgrass cultivar or cytotype (upland or lowland) can be confounded by differences in harvest date or region of growth. For this research, AFEX™ pretreatment conditions and hydrolysis enzyme mixtures were statistically optimized for Alamo (lowland) and Shawnee (upland) switchgrass that had been harvested in December in Oklahoma. Optimal pretreatment conditions and enzyme mixtures were almost identical for both varieties and gave similar mass sugar yields. Inclusion of hemicellulases in the enzyme mixture maintained total sugar yields with 50% reduction in enzyme loading. Regardless of variety, the biorefinery should be able to obtain high sugar yields using the same pretreatment and hydrolysis conditions to process switchgrass grown under the same environmental conditions, in the same location, and harvested at the same time of the year.
authors.affiliation: Biomass Conversion Research Laboratory, Department of Chemical Engineering and Materials Science, Michigan State University, MI 48824, USA. garlock1@msu.edu
authors.forename: Rebecca J
authors.initials: RJ
authors.lastname: Garlock
authors.forename: Venkatesh
authors.initials: V
authors.lastname: Balan
authors.forename: Bruce E
authors.initials: BE
authors.lastname: Dale
mesh_terms: D002241:Carbohydrates / Q000138:chemical synthesis*; D003198:Computer Simulation; D006026:Glycoside Hydrolases / Q000737:chemistry*; D008956:Models, Chemical; D008897:Panicum
chemical_list: D002241:Carbohydrates; D006026:Glycoside Hydrolases; C023305:hemicellulase