Abstract:
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 factor. The result of 2-level factorial design experiment showed thal all three independent
variables 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
consists of 20 experiments, which include 6 replicates at center points. The optimal value for each
variable is incubation time sixth days, temperature 27.830
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).
