Solid-state fermentation for xylanase production by Thermoascus aurantiacus using response surface methodology

We investigated xylanase production by Thermoascus aurantiacus using semiso lid fermentation. Multivariant statistical approaches were employed to eval uate the effects of several variables (initial moisture in the medium, cult ivation time, inoculum level, and bagasse mass) on xylanase production. The initial moisture content and bagasse mass were the most important factors affecting xylanase activity. The xylanase activity produced by the fungus u nder the optimized conditions (81% moisture content and 17 g bagasse) was f ound to be 2700 U per gram of initial dry matter, whereas its value predict ed by a polynomial model was 2400 U per gram of initial dry matter.