Although these data were promising, it was important to
clearly establish an effective ethylene dose range in the
laboratory prior to initiating large-scale crop storage,
greenhouse, or field experiments. The objective of the
current study was to optimize efficacy of ethylene treatment
by testing a wide range of ethylene concentrations
(using the flow-through model) for ability to inhibit
aflatoxin accumulation by A. parasiticus grown on peanuts
under conditions that generate much higher levels of toxin
accumulation than in the previous study. Ethylene reduced
aflatoxin accumulation in a dose-dependent manner
(0–100 ppm); the highest reduction (6-fold) was observed
at 100 ppm ethylene (atmospheric CO2 levels 0.03%).
CO2 alone at 0.1% inhibited aflatoxin accumulation;
however, 0.1% CO2 blocked the inhibitory effect of
ethylene when these treatments were combined.