Factors Affecting Antifungal Activity of Onion Extractives Against Aflatoxin-Producing Fungi

The processing factors, that could affect the inhibitory activity of onion extractives against the spores of Aspergillus parasiticus have been evaluated. The lachrymatory factor (thiopropanal-S-oxide) had maximal inhibitory activity. The survival of A. parasiticus spores depended upon the inhibitor concentration and the time of exposure of the spores to the onion inhibitors. Germinated spores showed more susceptibility to the inhibitors. The inhibitory effect of onion compounds was lost by heating, freeze-drying, dehydration, aeration and agitation, and prolonged storage.