The effects of different cultures on the production of xylanases and cellulases by Trichoderma reesei Rut C-30 on pretreated corn cob were studied. It was found that the production of xylanases and cellulases was regulated not only by the inducers, but also by the culture conditions, especially the pH-value, the temperature, and the C/N ratio. The formation of Cellulases could be repressed by controlling the culture conditions, resulting in a higher xylanase /cellulase ratio in the enzyme solutions obtained. Under complex regulatory control culture in 10-L bioreactor, a enzyme solution with xylanases (23.5 U/ml) and cellulases (0.12 U/ml) were obtained, with the xylanase/cellulase ratio reaching about 200. The method of the complex control culture was: pH4.8～5.0/5.5～6.5,temperature 35～36°C/28～29°C, air volume 0.15～0.2m~3/h, agitation 250～275 rpm, C/N 10.5～12.0, with the N source fed by batch. Results in the enzyme-aided bleaching of wheat straw Soda-AQ pulp indicated that the raw enzyme solution could be directly used in pulp bleaching.
展开▼
