title: Evaluation of wet oxidation pretreatment for enzymatic hydrolysis of softwood.
abstract: The wet oxidation pretreatment (water, oxygen, elevated temperature, and pressure) of softwood (Picea abies) was investigated for enhancing enzymatic hydrolysis. The pretreatment was preliminarily optimized. Six different combinations of reaction time, temperature, and pH were applied, and the compositions of solid and liquid fractions were analyzed. The solid fraction after wet oxidation contained 58-64% cellulose, 2-16% hemicellulose, and 24-30% lignin. The pretreatment series gave information about the roles of lignin and hemicellulose in the enzymatic hydrolysis. The temperature of the pretreatment, the residual hemicellulose content of the substrate, and the type of the commercial cellulase preparation used were the most important factors affecting the enzymatic hydrolysis. The highest sugar yield in a 72-h hydrolysis, 79% of theoretical, was obtained using a pretreatment of 200 degrees C for 10 min at neutral pH.
authors.affiliation: VTT Biotechnology, PO Box 1500, FIN-02044 VTT, Espoo, Finland.
authors.forename: Hetti
authors.initials: H
authors.lastname: Palonen
authors.forename: Anne Belinda
authors.initials: AB
authors.lastname: Thomsen
authors.forename: Maija
authors.initials: M
authors.lastname: Tenkanen
authors.forename: Anette S
authors.initials: AS
authors.lastname: Schmidt
authors.forename: Liisa
authors.initials: L
authors.lastname: Viikari
mesh_terms: D001709:Biotechnology / Q000379:methods*; D002241:Carbohydrates / Q000737:chemistry; D002480:Cellulase / Q000737:chemistry*; D002482:Cellulose / Q000737:chemistry; D004789:Enzyme Activation; D006026:Glycoside Hydrolases / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D008031:Lignin / Q000737:chemistry; D010084:Oxidation-Reduction; D010100:Oxygen / Q000737:chemistry; D011134:Polysaccharides / Q000737:chemistry; D011312:Pressure; D013696:Temperature; D013997:Time Factors; D014867:Water / Q000737:chemistry; D014934:Wood
chemical_list: D002241:Carbohydrates; D011134:Polysaccharides; D014867:Water; C007916:hemicellulose; D002482:Cellulose; D008031:Lignin; D006026:Glycoside Hydrolases; C023305:hemicellulase; D002480:Cellulase; D010100:Oxygen