Factors affecting cellulase production by Aspergillus fumigatus SK1 from solid state fermentation of oil palm empty fruit bunches using application of 2-level factorial design

Abstract

A study was conducted to screen parameters affecting the production of cellulase by Aspergillus fumigatus SK1 on solid state fermentation of oil palm empty fruit bunch using the application of 2-level factorial design. Through the two-Level full Factorial Design (2LFD), the experimental design was employed to screen the significant environmental factors for cellulase (CMCase, FPase and Ø-glucosidase) production. Full factorial de- sign of four factors with six center point was conducted which consist of 22 runs. All data obtained were then used as input to the Design Expert software for further analysis, according to steps outline. ANOVA analysis showed that the models were significant (p < 0.0001) for CMCase, FPase and Ø-glucosidase. Inoculum size, temperature, moisture and ammonium sulphate were identified as significant factor affecting cellulase production on solid state fermentation. Statistical analysis revealed that the linear model is significant with R2 value of 0.9569, 0.9867 and 0.9873 for CMCase, FPase and Ø-glucosidase production, respectively. Cellulase production was found to be high at the optimal condition were: inoculums size 109, moisture 74%, temperature 39 and ammonium sulphate 3.5 g/L. The obtained optimal process parameters predicted and verified by confirmation experiments with less than 5% error.