Production of endo-1,4-β-glucanase and xylanase with nylon-web immobilized and free Trichoderma reesei

Abstract

On all media studied, the endo-1,4-β-glucanase and xylanase activities obtained with the nylon-web immobilized Trichoderma reesei were higher than the activities with the free mycelium. The nitrogen source had a marked effect on endoglucanase and xylanase production on lactose, cellulose, and l-sorbose-based medium with immobilized T. reesei. The highest enzyme activities with this medium, 880 nkat ml −1 for endoglucanase and 8,020 nkat ml −1 for xylanase, were obtained in the presence of proteose peptone and yeast extract. Urea alone was an insufficient nitrogen source for enzyme production. A lactose-containing industrial by-product-based medium offered a good alternative for endoglucanase and xylanase production. In this case, the maximum endoglucanase activity was 940 nkat ml −1, xylanase activity was 4,410 nkat ml −1, and filter paper activity was 1.9 FPU ml −1. On synthetic cellulose-based medium, the activities were 840 nkat ml −1, 4.790 nkat ml −1, and 3.0 FPU ml −1, respectively. The nylon-web immobilized biocatalyst could be used for two successive batch cultures with only a little decrease in enzyme production observed.