African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5210

Full Length Research Paper

Optimization of medium composition for α-galactosidase production by Antarctic bacterial isolate, Bacillus sp. LX-1 using response surface methodology

  Jaekoo Lee1#, Inkyung Park1#, Sangbuem Cho2#, Sooki Kim1, Yunjaie Choi3, Jaiesoon Cho1*
  1Department of Animal Science and Technology, College of Animal Bioscience and Technology, Konkuk University, South Korea. 2Department of Animal Science, Chonbuk National University, Jeonju, 664-14, SouthKorea. 3Department of Agricultural Biotechnology, Seoul National University, South Korea.
Email: [email protected]

  •  Accepted: 26 April 2013
  •  Published: 05 July 2013



The optimization of medium composition for α-galactosidase production by an Antarctic bacterial isolate, Bacillus sp. LX-1 was investigated in flask fermentation. The Central composite design (CCD) with 3 variables (galactose, peptone and MnSO4) was employed to derive statistical model (Response surface methodology: RSM) for optimizing the medium composition. The results show the optimum medium composition of 16.5 g/L galactose, 6.2 g/L peptone and 0.0018 g/L MnSO4 with predicted α-galactosidase activity, 1.17 U/mL and observed activity from the fermentation with optimized medium was 1.06 U/mL. The optimized value was 6.3-fold higher than that (0.168 U/mL) previously obtained under basal conditions. Thus, medium optimization using RSM is suggested to play a significant role in enhancing the production of α-galactosidase by Bacillus sp. LX-1.


Key words: α-Galactosidase, Bacillus sp. LX-1, medium optimization, central composite design (CCD), response surface methodology (RSM).