title: Medium optimization for hen egg white lysozyme production by recombinant Aspergillus niger using statistical methods.
abstract: Statistics-based experimental design was used to investigate the effect of medium components (starch, peptone, ammonium sulfate, yeast extract, and CaCl2.2H2O) on hen's egg white lysozyme production by Aspergillus niger HEWL WT-13-16. A 2(5-1) fractional factorial design augmented with center points revealed that peptone, starch, and ammonium sulfate were the most significant factors, whereas the other factors were not important within the levels tested. The method of steepest ascent was used to approach the proximity of optimum. This task was followed by a central composite design to develop a response surface for medium optimization. The optimum medium composition for lysozyme production was found to be: starch 34 g L-1, peptone 34 g L-1, ammonium sulfate 11.9 g L-1, yeast extract 0.5 g L-1, and CaCl2.2H2O 0.5 g L-1. This medium was projected to produce, theoretically, 212 mg L-1 lysozyme. Using this medium, an experimental maximum lysozyme concentration of 209+/-18 mg L-1 verified the applied methodology.
authors.affiliation: Department of Chemical Engineering, University of Waterloo, 200 University Avenue West, N2L 3G1 Waterloo, Ontario, Canada. rgheshla@engmail.uwaterloo.ca
authors.forename: R
authors.initials: R
authors.lastname: Gheshlaghi
authors.forename: J M
authors.initials: JM
authors.lastname: Scharer
authors.forename: M
authors.initials: M
authors.lastname: Moo-Young
authors.forename: P L
authors.initials: PL
authors.lastname: Douglas
mesh_terms: D000465:Algorithms; D000818:Animals; D001234:Aspergillus niger / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism*; D019149:Bioreactors / Q000382:microbiology; D018929:Cell Culture Techniques / Q000379:methods*; D002645:Chickens; D003198:Computer Simulation; D003470:Culture Media / Q000378:metabolism; D008954:Models, Biological; D009113:Muramidase / Q000096:biosynthesis* / Q000235:genetics*; D015202:Protein Engineering / Q000379:methods*; D011994:Recombinant Proteins / Q000096:biosynthesis
chemical_list: D003470:Culture Media; D011994:Recombinant Proteins; C421864:hen egg lysozyme; D009113:Muramidase