Optimization of Chitinase Production by Trichoderma virens in Solid State Fermentation Using Response Surface Methodology

Physical factor for chitinase production by Trichoderma virens was first carried out using screening factor of 2-level factorial. The design was employed by selecting incubation time, temperature, moisture substrate, pH, inoculums size and concentration ammonium sulphate as a model factors. The result of 2-level factorial design experiment showed thal all three independent variable have significant effect on chitinase production. The physical factor was further optimized using Central Composite Design in which response surface was generated later from the derived model. An experimental design of three variables including various incubation time, temperature and moisture substrate were created using Design Expert® Software, Version 6.0.4 The design consist of 20 experiments, which include 6 replicate at center points. The optimal value for each variable are incubation time sixth days, temperature 27.83°C and moisture substrate 54% with predicted chitinase activity of 0.48738 U/g of dry substrate. These predicted parameters were tested in the laboratory and the final chitinase activity obtained was 0.48864 U/g of dry substrate, which is similar to the predicted value. The obtained value of the chitinase production was 0.48738 U/g IDS, which was 1.2 fold higher than that of the 2-level factorial design (0.261 U/gds)