PLANT-CELL-WALL-DEGRADING ENZYMES PRODUCED BY THE WHITE-ROT FUNGUS CERIPORIOPSIS-SUBVERMISPORA

The production of various plant-cell-wall-degrading enzymes by the whi te-rot fungus Ceriporiopsis subvermispora was monitored in shake-flask cultures, Analyses included various cellulolytic (i.e. endo-1,4-beta- glucanase, exo-1,4-beta-glucanase, 1,4-beta-glucosidase), hemicellulol ytic (i.e. xylanases, 1,4-beta-xylosidases, mannanases, 1,4-beta-manno sidases), and ligninolytic (i.e. laccase and manganese peroxidase) enz ymes, Other enzymes studied were polyendogalacturonase, proteases, amy lases, phenolic acid esterases and lipases, Glucose, cellobiose, avice l and Whatman cellulose were the primary carbon sources used, Other su bstrates were birch-wood xylan, galacto-mannan and citrus pectin, Grou nd stems of two fibrous plants, flax and kenaf, were the substrates re presenting a complete cell-wall composition used, Endo-1,4-beta-glucan ase and 1,4-beta-glucosidase activities were detected in certain cultu re solutions but, interestingly, pro significant amount of exo-1,4-bet a-glucanase activity was found in cultures of any of the carbon source s, Avicel, in general, gave rise to higher fungal growth and enzyme pr oduction compared to the more crystalline Whatman cellulose, Xylanase and mannanase activities were readily detected under all culture condi tions used, Flax and kenaf flour generally induced more enzyme product ion over xylan, mannan and pectin, Laccase and manganese peroxidase we re the two ligninolytic enzymes produced, Pectin, xylan and mannan ind uced more polyendogalacturonase than other substrates, Proteases and a mylases were also produced, but no lipase activity was detected, C. su bvermisporo also produced phenolic acid esterases in the avicel and xy lan cultures, Preference for a more amorphous cellulose, avicel and he micelluloses over a more crystalline Whatman cellulose as substrates f or active growth is most likely the reason for the lignin specificity of C. subvermispora. Enzyme profiles suggest that C. subvermispora sho ws a potential for various industrial applications where removal of th e lignin components, while maintaining cellulosic fibre strength prope rty, is important.