title: Production of cold-adapted amylase by marine bacterium Wangia sp. C52: optimization, modeling, and partial characterization.
abstract: The aim of this work was to optimize the fermentation parameters in the shake-flask culture of marine bacterium Wangia sp. C52 to increase cold-adapted amylase production using two statistical experimental methods including Plackett-Burman design, which was applied to find the key ingredients for the best medium composition, and response surface methodology, which was used to determine the optimal concentrations of these components. The results showed starch, tryptone, and initial pH had significant effects on the cold-adapted amylase production. A central composite design was then employed to further optimize these three factors. The experimental results indicated that the optimized composition of medium was 6.38 g  L(-1) starch, 33.84 g  L(-1) tryptone, 3.00 g  L(-1) yeast extract, 30 g  L(-1) NaCl, 0.60 g  L(-1) MgSO(4) and 0.56 g  L(-1) CaCl(2). The optimized cultivation conditions for amylase production were pH 7.18, a temperature of 20°C, and a shaking speed of 180 rpm. Under the proposed optimized conditions, the amylase experimental yield (676.63 U  mL(-1)) closely matched the yield (685.60 U  mL(-1)) predicted by the statistical model. The optimization of the medium contributed to tenfold higher amylase production than that of the control in shake-flask experiments.
authors.affiliation: Center for Bioengineering and Biotechnology, China University of Petroleum (East China), Qingdao, 266555, People's Republic of China.
authors.forename: Jianguo
authors.initials: J
authors.lastname: Liu
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Zhang
authors.forename: Zhiqiang
authors.initials: Z
authors.lastname: Liu
authors.forename: Hu
authors.initials: H
authors.lastname: Zhu
authors.forename: Hongyue
authors.initials: H
authors.lastname: Dang
authors.forename: Jianren
authors.initials: J
authors.lastname: Lu
authors.forename: Zhanfeng
authors.initials: Z
authors.lastname: Cui
mesh_terms: D000681:Amylases / Q000737:chemistry / Q000378:metabolism*; D003080:Cold Temperature; D041965:Flavobacteriaceae / Q000201:enzymology* / Q000502:physiology; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D015971:Gene Expression Regulation, Enzymologic / Q000502:physiology*; D006863:Hydrogen-Ion Concentration; D006868:Hydrolysis; D015203:Reproducibility of Results; D013213:Starch / Q000378:metabolism
chemical_list: D013213:Starch; D000681:Amylases