THE EFFECT OF OXIDATIVE PRETREATMENT ON CELLULOSE DEGRADATION BY PORIA-PLACENTA AND TRICHODERMA-REESEI CELLULASES

The possible role of hydrogen peroxide in brown-rot decay was investig ated by studying the effects of pretreatment of spruce wood and microc rystalline Avicel cellulose with H2O2 and Fe2+ (Fenton's reagent) on t he subsequent enzymatic hydrolysis of the substrates. A crude endogluc anase preparation fi-om the brown-rot fungus Poria placenta, a purifie d endoglucanase from Trichoderma reesei and a commercial Trichoderma c ellulase were used as enzymes. Avicel cellulose and spruce dust were d epolymerized in the H2O2/Fe2+ treatment. Mainly hemicelluloses were lo st in tl-le treatment of spruce dust. The effect of the pretreatment o n subsequent enzymatic hydrolysis was found to depend on the nature of the substrate and the enzyme preparation used. Pretreatment with H2O2 /Fe2+ clearly increased the amount of enzymatic hydrolysis of spruce d ust with both the endoglucanases and the commercial cellulase. In all cases the amount of hydrolysis was increased about threefold. The hydr olysis of Avicel with the endoglucanases was also enhanced, whereas th e hydrolysis with the commercial cellulase was decreased.