Abstract:

In this paper, strain Trichoderma Koningii QF-02 was cultivated in submerged state to produce cellulases and xylanase, and the effects of carbon source, initial pH value and cultivation time for the production of enzymes were investigated by single-factor and orthogonal experiments. The results show that   the variety and nature of carbon sources play an important role in the enzyme production;   rice straw is a good carbon source due to its high performance and low cost;   the optimal shake-flask culture conditions are： 4 g of straw powder; （40 meshes）, 100mL of Mandels solution and an initial pH value of 4. 5; and   after the cultivation in the optimal conditions for 144 h, the enzymatic activities of filter paper cellulase, β-glucosidase, and xylanase respectively reach 1.49FPU/mL, 0. 39U/mL, and 174. 10U/mL. Moreover, by comparing the saccharification ability of the compos- ite enzyme produced by Trichoderma Koningii with that of a commercial cellulase, it is found that, when using the produced enzyme to treat alkali-pretreated straw and natural straw, the yields of total reducing sugar respectively increase by 55% and 40% , and the yields of glucose respectively increase by 33% and 12%.

Key words: Trichoderma koningii, submerged fermentation, cellulase, xylanase