Lignocellulose degradation by Pleurotus ostreatus in the presence of cadmium

Activities of cellulolytic and hemicellulolytic enzymes endo-1,4-beta-glucanase, exo-1,4-beta-glucanase, 1,4-beta-glucosidase, endo-1,4-pxylanase, 1,4-beta-xylosidase and 1,4-beta-mannosidase and ligninolytic enzymes Mn-peroxidase and laccase were detected during the growth of the white-rot fungus Pleurotus ostreatus on wheat straw in the presence and absence of cadmium. The loss of substrate dry weight and Mn-peroxidase activity decreased with increasing Cd concentration, whereas the activities of endo-1,4-beta-glucanase, 1,4-beta-glucosidase and laccase were highly increased in the presence of metal. The onset of hemicellulose-degrading enzyme activity was delayed in the presence of cadmium. The degradation of a model synthetic dye Poly B-411 did not correspond to the activities of ligninolytic enzymes. This is the first report about 1,4-beta-mannosidase in P. ostreatus. (C) 2003 Federation of European Microbiological Societies. Published by Elsevier Science B.V. All rights reserved.