Optimization of Cellulase Production by Trichoderma Strains Using Crude Glycerol as a Primary Carbon Source with a 24 Full Factorial Design

' This work focuses on the optimization of cellulase production by two Trichoderma strains. A 2(4) full factorial design was used to evaluate the effects of four factors in the optimization of cellulase production (filter paper assay-FPA): crude glycerol, microcrystalline cellulose, yeast extract and ammonium sulfate. In fermentation with Trichoderma CMIAT 054 strain the largest FPA (138.48 FPU L-1) occurred with 25.0 g L-1 of cellulose, 10.0 g L-1 of crude glycerol, 1.4 g L- 1 of yeast extract and 3.5 g L- 1 of ammonium sulfate in the culture medium. In tests with Trichoderma CMIAT 041 strain the highest FPA (89.35 FPU L-1) occurred with 25.0 g L-1 of cellulose, 20.0 g L-1 of crude glycerol, 0.6 g L-1 of yeast extract and 1.5 g L-1 of ammonium sulfate in the culture medium. ANOVA showed a correlation coefficient of 93 and 88% for Trichoderma CMIAT 054 and CMIAT 041 strains, respectively. Reduced regression models for the cellulase produced by these strains were obtained.