Alpha-Xylosidase: A New Enzyme for Enhanced Conversion of Lignocellulosic Biomass to Fermentable Sugars
Producing cellulosic ethanol from biomass feedstock such as corn stover requires the breakdown of sturdy cell wall materials, including cellulose, hemicellulose, and lignin, into fermentable sugars. This breakdown is facilitated commercially by various enzyme cocktails. However, the high cost of enzymes has been a major barrier to reducing the production cost of cellulosic ethanol to a competitive level. Researchers at Michigan State University (MSU) have discovered an enzyme, an alpha-xylosidase, which greatly increases the efficiency of enzyme mixtures. The use of this enzyme allows for higher sugar yields and lowers the cost of producing cellulosic ethanol.
Currently, none of the major enzyme cocktails used for biomass deconstruction in cellulosic ethanol production contain alpha-xylosidase. The gene is not present in the genome of the major source of commercial cellulases. Alpha-xylosidase, naturally produced by the fungus Aspergillus niger and active in the same temperature and pH ranges as the currently used enzyme cocktails, increases the yield of fermentable sugars (glucose and xylose) from biomass feedstock by up to 10%. This technology can be used on an industrial scale to lower the production cost for cellulosic ethanol. The invention has the potential to make a significant contribution towards making ethanol production based on sustainable, non-food feedstock competitive.
- Increased yields of xylose and glucose
- Lowers cellulosic ethanol production cost in industrial environment
- Effective in same temperature and pH-range as existing enzyme cocktails
- Ethanol production, possible use as detergent and fabric softener
Thomas Herlache Assistant Director Michigan State University herlache@msu.edu