Fermentation And Application Of Neutral Cellulase From Trichoderma ZC

The mutant strain ZC-298, which had been treated with N+, NTG and L-sorbose, wasisolated with effectual screening method from the neutral-cellulase-producing strain ZC-I(Trichoderma sp.). The enzymatic activity of the mutant was increased about 2 times, whichwas 4.24 IU/mL.After a series of experiments, the optimum culture conditions for flask were established.The optimum medium: Avicel 2.14%, corn cob 1.98%, bean cake 2.17%, bran 0.5%,(NH4)2SO4 0.2%, KH2PO4 0.2%, MgSO4 0.03%, CaCl2 0.03%. The other conditions: volumeof medium is 100ml/250ml, culture temperature is 30℃, the speed of rotary shaker is150r/min.Under these conditions, the Filter Paper Activity (FPA) could be achieved6.5-7.4IU/mL.The optimum culture conditions for 30L fermenter were established. In the second day offermentation, 2%Avicel should be added. In the end of fermentation, pH should be controlledby NH3·H2O. Under these conditions, the FPA could be achieved 4.5-6.0IU/mL.The concentrate liquid enzymes were prepared by plate filter and ultrafiltrationtechnology. The total yield of liquid enzyme was 75%, and its FPA could be achieved15-20IU/mL.Several effective cellulase promoters were tested, and the compound cellulasepreparations were achieved. The application of the compound cellulase preparations had beenalso studied, and the preparations proved highly effective.