African Journal of
Biotechnology

  • Abbreviation: Afr. J. Biotechnol.
  • Language: English
  • ISSN: 1684-5315
  • DOI: 10.5897/AJB
  • Start Year: 2002
  • Published Articles: 12227

Full Length Research Paper

Production of alkaline proteases by alkalophilic Bacillus subtilis during recycling animal and plant wastes

Amira Hassan Al-Abdalall*
  • Amira Hassan Al-Abdalall*
  • Department of Biology, Faculty of Science, University of Dammam, El-Dammam, Kingdom of Saudi Arabia.
  • Google Scholar
Eida Marshid Al-Khaldi
  • Eida Marshid Al-Khaldi
  • Department of Biology, Faculty of Science, University of Dammam, El-Dammam, Kingdom of Saudi Arabia.
  • Google Scholar


  •  Received: 24 April 2016
  •  Accepted: 24 October 2016
  •  Published: 23 November 2016

Abstract

The production of extracellular alkaline protease by Bacillus subtilis was studied with submerged fermentation. A new strain of Bacillus sp. was isolated from alkaline soil, which was able to produce extracellular alkaline protease. The production of alkaline protease involved the use of agricultural or animal wastes at pH 8 and temperatures at 37°C. Results showed that growing B. subtilis sub sp. subtilis under optimized growth resulted in production of alkaline protease with enzyme activity of 1412.5 U/ml, while with pomegranate peel at a concentration of 3%, the enzyme activity reached 3600 U/ml; further increase in pomegranate concentration did not however, lead to additional enzyme activity. Among various nitrogen sources, yeast extract was found to be the best inducer of alkaline protease. Among metal salts, KNO3 and NH4Cl were found to increase protease production. The maximum enzyme production (3600 U/ml) was observed with pomegranate peels of fermentation medium in the presence of yeast extract, potassium nitrate and ammonium chloride.

Key words: Production, alkaline protease, Bacillus subtilis, animal wastes, enzyme activity.