Evaluation of Cellulase Preparations for Hydrolysis of Hardwood Substrates ALEX BERLIN,* ,1 NEIL GILKES, 1 DOUGLAS KILBURN, 1 VERA MAXIMENKO, 1 RENATA BURA, 1 ALEXANDER MARKOV , 2 ANTON SKOMAROVSKY , 2 ALEXANDER GUSAKOV , 2 ARKADY SINITSYN, 2 OLEG OKUNEV , 3 IRINA SOLOVIEVA, 3 AND JOHN N. SADDLER 1 1 Forest Products Biotechnology, Faculty of Forestry, The University of British Columbia, Vancouver, BC V6T 1Z4, Canada, E-mail: alex.berlin@ubc.ca; 2 Department of Chemical Enzymology, Faculty of Chemistry, M. V. Lomonosov Moscow State University, Vorobyevy Gory, Moscow 119899, Russian Federation; and 3 Institute of Biochemistry and Physiology of Microorganisms, Russian Academy of Sciences, Pushchino, Moscow Region 142292, Russian Federation Abstract Seven cellulase preparations from Penicillium and T richoderma spp. were evaluated for their ability to hydrolyze the cellulose fraction of hardwoods (yellow poplar and red maple) pretreated by organosolv extraction, as well as model cellulosic substrates such as filter paper. There was no significant correlation among hydrolytic performance on pretreated hardwood, based on glucose release, and filter paper activity. However, performance on pre- treated hardwood showed significant correlations to the levels of endogenous β-glucosidase and xylanase activities in the cellulase preparation. Accordingly, differences in performance were reduced or eliminated following supple- mentation with a crude β-glucosidase preparation containing both activities. These results complement a previous investigation using softwoods pre- treated by either organosolv extraction or steam explosion. Cellulase prepa- rations that performed best on hardwood also showed superior performance on the softwood substrates. Index Entries: Cellulase; xylanase; hemicellulose; lignocellulose; bio- conversion. Introduction Concerns about diminishing resources, national energy security, and the excessive production of greenhouse gases continue to motivate the search for alternatives to petroleum. Lignocellulosic biomass contains large Applied Biochemistry and Biotechnology 528 Vol. 129–132, 2006 Copyright © 2006 by Humana Press Inc. All rights of any nature whatsoever reserved. 0273-2289/06/129–132/528–545/$30.00 *Author to whom all correspondence and reprint requests should be addressed.