Kinetics of growth and accumulation of aflatoxin B(1) by Aspergillus parasiticus in the presence of butylated hydroxyanisole, isoprothiolane, and nystatin.
Growth of Aspergillus parasiticus and accumulation of aflatoxin B(1) in the medium that contained antifungal agents were monitored during the growth cycle of the mold. The antifungal agents tested are the food additive (antioxidant), butylated hydroxyanisole (BHA), the pesticide, isoprothiolane, and the antibiotic, nystatin. Growth of the mold was quantified using a newly developed criterion, named the growth coefficient (GC). The GC values were calculated from the growth parameters of the logistic function that fits the growth curve of the mold. At the range of concentrations of additives studied, maxima of growth inhibition were 31.3, 23.1, and 43.6% at 60 ppm of BHA, 70 ppm of isoprothiolane, and 45 units of nystatin/mL, respectively. The ability of the mold to accumulate aflatoxin B(1) in its medium [as measured by the accumulation rate constant (alpha)] In the presence of various levels of the antifungal agents was concentration-dependent. Sixty parts per million of BHA decreased the value of alpha by 71.7%, 30 units of nystatin/mL was the most effective concentration of that antibiotic and resulted in only 23.5% inhibition, and isoprothiolane at all its levels stimulated elaboration of aflatoxin B(1) by the mold.
Yousef
A E
AE
Department of Food Science and the Food Research Institute, University of Wisconsin-Madison, Madison, Wisconsin 53706.
Marth
E H
EH