Effect of pH, Cultivation Time and Substrate Concentration on the Endoxylanase Production by Aspergillus awamori ZH-26 under Submerged Fermentation Using Central Composite Rotary Design

The effect of substrate concentration, pH and cultivation time on the production of endoxylanase from Aspergillus awamori ZH-26 were optimized by statistical analysis using response surface methodology (RSM). Endoxylanase production was optimized by central composite rotary design. Statistical analysis of the results showed that the linear and quadratic terms of these three variables had significant effects. But no interactions between the three variables were found to contribute to the response at a significant level. The optimal conditions were: wheat bran 49.3 g/L, pH=4.14, and cultivation time 103.7 h. Under these conditions, the model predicted an endoxylanase activity of 28.25 U/mL. Verification of the optimization showed that endoxylanase production of 29.65 U/mL was observed under optimal conditions.