Characterization of hemicellulases and cellulases produced by Ceriporiopsis subvermispora grown on wood under biopulping conditions

Abstract: Production of cellulases and hemicellulases by Ceriporiopsis subvermispora cultured on wood chips of Eucalyptus grandis and Pinus taeda was studied. Xylanase, endo-1,4 β-glucanase, mannanase, β-glucosidase and β-xylosidase were detected in enzymatic extracts obtained after 30 days of cultivation. P. taeda gave rise to higher enzyme production compared to E. grandis. Biochemical characteristics of cellulases and hemicellulases produced in both wood species were almost the same. The optimum pH for the enzymes was between 4.0 and 5.0 and the optimum temperature was 60°C. Thermal stability of the enzymes at pH 5.0 was appreciable up to 50°C. The profile of proteins contained in extracts recovered from both biotreated wood species showed a similar number of bands during SDS-PAGE electrophoresis. Five bands with molecular weight ranging from 50 to 85kDa and two bands with high molecular weight (100–200kDa) were observed. Activity staining for xylanases indicated two enzymes with molecular weight of 80 and 33kDa. [Copyright &y& Elsevier]