African Journal of
Microbiology Research

  • Abbreviation: Afr. J. Microbiol. Res.
  • Language: English
  • ISSN: 1996-0808
  • DOI: 10.5897/AJMR
  • Start Year: 2007
  • Published Articles: 5232

Full Length Research Paper

Isolation and characterization of a thermostable α-amylase from Bacillus subtilis

S. Shafaat, M. Akram and A. Rehman*
Department of Microbiology and Molecular Genetics, University of the Punjab, New Campus, Lahore 54590, Pakistan.
Email: [email protected]

  •  Accepted: 22 August 2011
  •  Published: 30 September 2011


The present study is aimed at assessing the ability of Bacillus subtilis to convert starch into reducing sugars. Maximum enzyme activity showed by B. subtilis was 236 Uml-1B. subtilis showed optimum growth at pH 8 and optimum temperature for the growth of bacterial isolate was found to be 45°C. The optimal pH and temperature of the amylase activity were 7.0 and 37°C, respectively. The enzyme was found to be stable in the pH range of 5 to 10. Maximum α-amylase activity was determined in 1% starch. The enzyme was found to be in two forms with relative molecular mass of 43 and 18 kDa in SDS-polyacrylamide gel electrophoresis. B. subtilis can be exploited for starch conversion biotechnologies.


Key words: Starch, α-amylase, Bacillus subtilis.