Biodeterioration potentials of fungal isolates from vegetable oils.

The biodeterioration potentials of fungi isolated from vegetable oils were investigated. Growth of pure cultures of some mould species (Aspergillus flavus, Aspergillus niger, Aspergillus sp., Penicillium sp. and Fusarium sp.) and a mixed yeast culture (Saccharomyces sp., Candida sp. and Hansenula sp.) were monitored using six vegetable oils as substrates. Mould growth resulted in an increase in mycelial dry weight (g/100 ml) of the cultures in all the oils. Yeast growth in the oils caused decrease in pH, increase in optical density and increase in total viable count (TVC) in all the oils. Gas chromatographic analysis of the heptane extracts of the oils revealed that inoculated and uninoculated oil samples displayed similar chromatograms. Yeast growth in the oils also resulted in loss of some fatty acid components as well as biosyntheses of new ones.