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.