701b Enzymatic Extraction of Wood Hemicellulose

Hyun-Dong Shin, Tien Le, Christopher Clarke, and Rachel Ruizhen Chen. School of Chemical and Biomolecular Engineering, Georgia Institute of Technology, 778 Atlantic Dr, Atlanta, GA 30332

Previously, we discovered Neosartorya spinosa NRRL185 as a microbe capable of producing useful cellulases and hemicellulases for biomass processing. The dynamics of enzyme production were dependent on the nature of biomass used for cell growth such that a tunable enzyme mixture tailored for a particular application could be obtained. The present research investigates extraction of wood hemicellulose using the enzymes from this organism. This process is intended to be used before pulping in a paper mill in order to extract values from hemicellulose, which otherwise is lost in the waste stream. The enzymatic extraction is advantageous over other recovery methods in its mild conditions (room temperature, ambient pressure, and neutral pH), and is unlikely to cause damage to cellulose fibers. There will be no chemicals involved in the treatment, no excessive use of energy source, and no consequential environmental concerns. This recovery step extracts significant and desired percentage of the >25% hemicelluloses (mostly glucomannan) from wood material, substantially increasing the material use from current 50%. The enzymatic process does not alter the downstream pulp and paper process, and the degree of extraction can be readily controlled through the amount of enzymes and treatment time so that the paper quality will not be compromised. Cells will grow with wood biomass as the sole carbon and energy source, and enzymes produced will be characterized using available biochemical methods. The extracellular enzymes harvested at different cultivation conditions will be tested for their effectiveness of hemicellulose extraction from wood substrate. The recovered hemicelluloses will be c used as raw material in the fermentation process to produce bioethanol and chemicals such as lactic acid. This study demonstrates the feasibility of building a biorefinery platform, along with the core paper business within a paper mill, explores the various biorefinery options in which products including ethanol and lactic acid are produced.