title: The effects of increasing swelling and anionic charges on the enzymatic hydrolysis of organosolv-pretreated softwoods at low enzyme loadings.
abstract: Organosolv-pretreated Lodgepole pine substrates were physically and chemically treated to increase their hydrophilicity and swelling as these are two substrate attributes which have been shown to improve cellulolytic hydrolysis. Surprisingly, mechanical treatment of the organosolv-treated substrates by PFI-mill refining did not significantly increase hydrolysis yields despite decreases in particle size and crystallinity and increases in swelling. However, sulfonation of the substrate did, significantly, increase enzymatic hydrolysis at loadings of both 5 and 2.5 FPU g(-1) cellulose (from 80% to 95% and from 35% to 80%, respectively). In addition, sulfonation resulted in an increase in the amount of free enzymes detected during the course of hydrolysis to a maximum of 80% after 72 h. This suggested that the beneficial effects of sulfonation were primarily due to a decrease in the non-specific binding of the cellulases to the lignin.
authors.affiliation: Forest Products Biotechnology/Bioenergy Group, Department of Wood Science, Faculty of Forestry, University of British Columbia, 2424 Main Mall, Vancouver, British Columbia, Canada V6T 1Z4.
authors.forename: Luis F
authors.initials: LF
authors.lastname: Del Rio
authors.forename: Richard P
authors.initials: RP
authors.lastname: Chandra
authors.forename: John N
authors.initials: JN
authors.lastname: Saddler
mesh_terms: D002482:Cellulose / Q000378:metabolism; D004798:Enzymes / Q000378:metabolism*; D006868:Hydrolysis; D028223:Pinus / Q000737:chemistry / Q000378:metabolism; D055672:Static Electricity; D014934:Wood / Q000737:chemistry / Q000378:metabolism*
chemical_list: D004798:Enzymes; D002482:Cellulose