culture media (Roze et al., 2004). To analyze effects of
combined gases on peanuts, we used the following
treatments: air, 0.1% CO2, 2 ppm ethylene, 100 ppm
ethylene, 0.1% CO2+2ppm ethylene, and 0.1%
CO2+100 ppm ethylene. Gas concentrations were measured
on days 1, 2, 3, and 5 (not shown). As in the ethylene
dose–response experiment, the CO2 scrubber effectively
maintained CO2 levels at or slightly below atmospheric
levels.
The largest effect on reduction of aflatoxin B1 was
observed with 100 ppm ethylene (Fig. 3). Treatment with
CO2 alone (0.1%) generated a similar inhibitory effect on
aflatoxin accumulation. However, unlike the situation with
culture media, co-treatment of peanuts with both ethylene
(either 2 or 100 ppm) and CO2 (0.1%) did not show a
statistically significant inhibitory effect. TLC confirmed the
ELISA data (not shown). Treatment had no discernable
effect on mold growth as determined by visual inspection.
Our goal is to identify novel, safe, practical, and effective
means to reduce aflatoxin contamination in susceptible
food and feed crops. We focused initial attention on the use
of food-safe gases; an ideal gaseous compound for
application in food would be inexpensive, easy to apply,
would yield no residue, and would be effective at low
concentrations. Ethylene is characterized by these properties.
It has also been used effectively in a variety of
agricultural applications for decades and was found to
have no negative impact on the nutritive value of certain
fruits (reviewed in Kays and Beaudry, 2002).