Inhibition of T-2 toxin production on high-moisture corn kernels by modified atmospheres.

The fungus Fusarium sporotrichioides, capable of producing T-2 toxin (T-2), was grown on irradiated corn kernels remoistened to 22% and kept in atmospheres of different CO2-O2 combinations. The production of T-2 was totally inhibited under 60% CO2-20% O2, whereas only trace amounts were detected when the gas combination was 40% CO2-5% O2. Under all other combinations tested, the amount of T-2 produced was reduced by 25 to 50% as compared with the control. Fungal growth was not inhibited by any of the gas mixtures examined, and the growth rate (measured by direct plating, dilution method, and CO2 production) was almost identical to that in grains kept under air. It is concluded that although F. sporotrichioides is tolerant to high CO2 levels, T-2 formation on corn can be inhibited by CO2 concentrations less than that required to inhibit fungal growth.