Optimization of extracellular xylanase production by Sclerotinia sclerotiorum S2 using factorial design

The improvement of xylanase production by Sclerotinia sclerotiorum S2 using a liquid fermentation Culture was investigated. The optimized process was divided into three basic steps: (i) evaluating xylanase inducers using different agricultural residues Such as wheat bran, oat bran, orange peel and barley bran at 1% final concentration, and also filter paper. Among these, wheat bran showed the maximum activity (2.5 U/ml) at 12 days post-inoculation; (ii) for optimization, we determined the optimal concentration of inducer, the effect of phosphate anion (K(2)HPO(4)/KH(2)PO(4)) and culture aeration using a rotary shaker at 100 and 180 rpm. The optimal conditions For these three factors were determined in ail experimental panel using factorial data, in which a mathematical model (Minitab software) was fitted; (iii) The optimized culture medium containing a high level of wheat bran (3%) without KH2PO4-K2HP04 and submitted to a high agitation (180 rpm/min) increased the xylanase production from 2.5 U/ml to 4 U/ml (1.6-fold).