African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12191

Full Length Research Paper

Optimization of medium composition for cis-epoxysuccinate hydrolase production in Escherichia coli by response surface methodology

Hai-feng Pan[1], Wen-na Bao2, Zhi-peng Xie1* and Jian-guo Zhang1,2
[1]Institute of Biochemistry, Zhejiang University, Hangzhou 310058, PR China. 2Hangzhou Bioking Biochemical Engineering Co., Ltd., Hangzhou 311106, PR China.
Email: [email protected]

  •  Accepted: 17 November 2008
  •  Published: 01 March 2010

Abstract

Response surface methodology was applied to identify and optimize the medium composition for the cis-epoxysuccinate hydrolase production in recombinantEscherichia coli. Plackett-Burman design was used in the first step to evaluate the effects of 8 variables on the enzyme activity. CaCl2, corn steep liquor and lactose were screened as significant factors and their concentrations were further optimized using response surface methodology based on 23 full factorial rotatable central composite design. The optimum predicted medium for maximum expression of recombinant cis-epoxysuccinate hydrolase was found to comprise: 17.1 g/l Na2HPO4·12H2O, 2.0 g/l KH2PO4, 0.5 g/l NaCl, 1.0 g/l NH4Cl, 0.0111 g/l CaCl2 and 0.5 g/l MgSO4·7H2O, 17.18 ml/l corn steep liquor and 9.74 g/l lactose, with a predicted enzyme activity of 35490 U/g biomass, which was very close to the experimental activity of 36318 U/g biomass resulting in 1.7-fold increment after optimization.

 

Key words: Medium, optimization, response surface methodology, cis-epoxysuccinate hydrolase, Escherichia coli.