Journal of
Toxicology and Environmental Health Sciences

  • Abbreviation: J. Toxicol. Environ. Health Sci.
  • Language: English
  • ISSN: 2006-9820
  • DOI: 10.5897/JTEHS
  • Start Year: 2009
  • Published Articles: 208

Full Length Research Paper

Lipase production by strains of Aspergillus species isolated from contaminated body creams

Brooks A. A.1* and Asamudo N. U.2
1Department of Microbiology, University of Calabar, Nigeria. 2Department of Microbiology, University of Uyo, Nigeria.
Email: [email protected]

  •  Accepted: 12 August 2011
  •  Published: 31 October 2011

Abstract

Aspergillus species isolated from contaminated body creams were screened for their ability to produce extracellular lipase. Of the 6 strains tested two, identified as Aspergillus niger AC-5 and AC-7 and one strain ofAspergillus fumigatus. AF-3 were capable of producing extracellular lipase in appreciable amounts. A. nigerAC-5 was the highest lipase producer, followed by A. fumigatus AF-3, while Aspergillus flavus showed the least potential for lipase production. The maximal lipase production (14.4 µ/ml) was produced by strain AC-5 in 6 days culture supplied with 3% (v/v) olive oil as the carbon source. The optimum pH and temperature for the crude lipase activity were 6.5 and 40°C respectively, for strains tested. The enzyme was stable over a wide range of pH and temperature. The enzymes retained certain levels of their original activities when assayed at 60°C for 1 h. Body creams contaminated with these lipolytic moulds produced off-odours in addition to other physico-chemical changes such as discolouration, formation of tints and scum, emulsion breakage and changes in pH. This is a source of concern and calls for urgent amendment in the existing formulation protocols and strict adoption of good manufacturing practice to ensure microbiologically stable product.

 

Key words: Lipase, body cream, lipolytic molds, physico-chemical changes.