title: Optimization of nutrient medium containing agricultural wastes for xylanase production by Aspergillus niger B03 using optimal composite experimental design.
abstract: The xylanase biosynthesis is induced by its substrate - xylan. The high xylan content in some of the wastes like corn cobs and wheat bran makes them an accessible and cheap source of inducers. Nutrient medium for xylanase biosynthesis in submerged cultivation of Aspergillus niger B03 has been optimized. The optimization process was analyzed using optimal composite experimental design and response surface methodology. The predicted by the regression model optimum components of nutrient medium are as follows (g/l): (NH(4))(2)HPO(4) 2.6, urea 0.9, corn cobs 24.0, wheat bran 14.6 and malt sprout 6.0. Five parallel experiments have been carried out, at definite, optimum components concentrations of the nutrient medium, and a mean value of the activity Y=996.30 U/ml has been obtained. The xylanase activity, obtained with the optimized nutrient medium is 33% higher than the activity, achieved with the basic medium.
authors.affiliation: University of Food Technologies, Department of Biochemistry and Molecular Biology, 26 Maritza Boulevard, Plovdiv 4002, Bulgaria. g_dobrev2002@yahoo.fr
authors.forename: Georgi Todorov
authors.initials: GT
authors.lastname: Dobrev
authors.forename: Ivan Genov
authors.initials: IG
authors.lastname: Pishtiyski
authors.forename: Veselin Stanchev
authors.initials: VS
authors.lastname: Stanchev
authors.forename: Rositza
authors.initials: R
authors.lastname: Mircheva
mesh_terms: D000383:Agriculture; D001234:Aspergillus niger / Q000254:growth & development / Q000378:metabolism*; D003470:Culture Media / Q000592:standards*; D043364:Endo-1,4-beta Xylanases / Q000096:biosynthesis*; D008954:Models, Biological; D014866:Waste Products / Q000032:analysis*
chemical_list: D003470:Culture Media; D014866:Waste Products; D043364:Endo-1,4-beta Xylanases