Studies on a wild strain of Schizophyllum commune: Cellulase and xylanase production and formation of the extracellular polysaccharide Schizophyllan

Abstract

A wild strain of schizophyllum commune (Fr:Fr:) isolated in Bangladesh produced cellulase and xyianase in high yields as well as the exobiopolymer schizophyllan. It was found experimentally that concentrations of 4% Avicel, 3.5% peptone, and 0.5% Ca(NO₃)₂·4H₂O were optimal for growth and product formation. Bacto‐peptone was found to be the most suitable substrate of a number of casein, mycological, and meat peptone preparations for enzyme production. Young plate‐culture inocula (4 days) were found to be better than comparatively aged fungal cultures (14 days). With the optimized medium, 5 units filter paper (FP) cellulase, 1244 units xylanase, 108 units β‐glucosidase, and 65 units of carboxymethyl (CM) cellulase per mL culture filtrate were obtained in shake flasks. In a laboratory fermentor the respective enzyme activities were 4.5 units FP‐cellulase, 1200 units xylanase, 100 units β‐glucosidase, and 60 units CM‐cellulase per mL culture filtrate. A biopolymer, reported to be active against can cerous cells, was an additional product in addition to the enzymes.