Studies On The Production Processes, Properties And Kinetics Of Chitosanase With Trichoderma Viride

In this thesis, the author investigated the influence factors on the chitosanase generation of Trichoderma viride867, and its kinetics as well. The inhibitor effect on the activity of chitosanase of urea was also studied by kinetics methods.Chitosanase was produced by fermentation of two steps method of mycelium culture and induced enzyme generation separation. It was found that amino glucose is effective inducer of chitosanase generation. The optimal condition for chitosanase generation is: age of the fungus 40 h; culture time 36 h; culture temperature 30 ; initial pH of culture medium 7.0; rotate speed 200 rpm; amino glucose added in culture medium 0.01%; chitosan powder 2.0%; Tween-80 0.1%; major element solution 10 mL; minor element solution 1 mL; peptone, barm cream, beef cream 0.1% for each; liquid in waving flask100mL. In the above optimal condition, the output of chitosanase is 4.82 U/mL.The chitosanase generated by Trichoderma viride867 is high specific to substrates. It has no effects on colloid chitin and CMC. The catalyze effect of chitosanase reaches to its maximum value under weakacid circumstance of pH 5.0~6.0, and the chitosanase is insusceptible to lost its activity under the above circumstance. The optimal reaction temperature is 55 , and the chitosanase is tend to lost its activity when the temperature get higher than 60 .Heavy metal ions and urea have relatively strong inhibition effect, while Ca2+ has activation effect to some extent.The Michaelis constant Km of the chitosanase is 10.14 g/L, Vmax is 0.163 g/L-min. Urea was deduce to be competitive inhibitor of chitosanase by kinetics methods, and it was found that the inhibition constant Kf of urea to chitosanase is 0.762 mol/L.