Statistical screening method for selection of important variables on xylitol biosynthesis from rice straw hydrolysate by Candida guilliermondii FTI 20037

Fourteen assays were conducted to study the influence of different variable s, namely xylose concentration, inoculum level, agitation speed and nutrien t supplementation, on xylitol biosynthesis by Candida guilliermondii FTI 20 037. The maximum predicted values for xylitol yield (0.65 g g(-1)) and xyli tol productivity (0.66 g l(-1) h(-1)) can be attained with rice straw hydro lysate containing 60 g xylose l(-1) without supplementation of ammonium sul fate, calcium chloride and rice bran extract, using 5 g inoculum l(-1), at 250 rpm. Xylose concentration and inoculum level were selected for further optimization studies.