title: Production of glutaminase (E.C.3.2.1.5) from Zygosaccharomyces rouxii: statistical optimization using response surface methodology.
abstract: A face centered central composite design was employed to investigate the interactive effects of four variables, viz. concentrations of sucrose, yeast extract, sodium chloride, and glutamine, identified earlier by one-factor-at-a-time approach, on glutaminase production by Zygosaccharomyces rouxii. A significant influence of yeast extract on glutaminase production was noted. Response surface methodology (RSM) showed that a medium containing (g/l) sucrose, 17.8; yeast extract, 48.0; glutamine, 5.0 and sodium chloride, 55.6 to be optimum for the production of glutaminase. This medium was projected to produce, theoretically, an enzyme activity of 149.98 U/l and a specific activity of 0.488 U/mg protein. The applied methodology was validated using this optimized media and enzyme activity 155.89+/-1.68 U/l and specific activity of 0.468+/-0.088 U/mg protein was obtained. Further, this optimization strategy combined with an increase in inoculum enhanced the enzyme activity and specific activity by 2.94 and 3.58 fold, respectively, as compared to the unoptimized media.
authors.affiliation: Food Engineering and Technology, Department, Institute of Chemical Technology, University of Mumbai, Matunga, Mumbai 400 019, India. iyer_padma@rediffmail.com
authors.forename: Padma
authors.initials: P
authors.lastname: Iyer
authors.forename: Rekha S
authors.initials: RS
authors.lastname: Singhal
mesh_terms: D000704:Analysis of Variance; D018533:Biomass; D019149:Bioreactors; D001709:Biotechnology / Q000379:methods*; D003470:Culture Media; D005285:Fermentation; D005972:Glutaminase / Q000032:analysis* / Q000737:chemistry; D005973:Glutamine / Q000032:analysis; D008956:Models, Chemical; D015233:Models, Statistical; D012965:Sodium Chloride / Q000032:analysis; D013395:Sucrose / Q000032:analysis / Q000737:chemistry; D013499:Surface Properties; D013997:Time Factors; D020068:Zygosaccharomyces / Q000201:enzymology*
chemical_list: D003470:Culture Media; D005973:Glutamine; D012965:Sodium Chloride; D013395:Sucrose; D005972:Glutaminase