Optimization of xylanase production by Sporotrichum thermophile using corn cobs and response surface methodology

A 3(2) central composite experimental design was performed with the aim of optimizing the production of xylanase by Sporotrichum thermophile grown on corn cobs in submerged cultures. Various carbon and nitrogen sources were consecutively optimized, and corn cobs and ammonium phosphate concentrations were selected as substrates to test the effect of two variables, i.e., both substrate concentrations, on xylanase production. A second-order quadratic model and a response surface method showed that the optimum conditions for xylanase production were 2.7% [w/v] corn cobs and 0.7% [w/v] ammonium phosphate. These optimum conditions were transferred to 7 L bioreactors, where activities as high as 56 U/mL were obtained.