Aflatoxin B1, zearalenone and deoxynivalenol production on irradiated corn kernels: Influence of inoculum size.

The influence of inoculum size on aflatoxin B1 (AFB1), zearalenone (ZEN) and deoxynivalenol (DON) production was examined on irradiated corn kernels.Spore concentrations were determined in serial dilutions and adjusted to 10,10(2),10(3),10(5) and 10(6) spores/ml. Aflatoxin B1 production was dependent on the inoculum size. The high levels of aflatoxin B1 produced byA. parasiticus (21 and 30 mg/kg) were obtained with 10(2) and 10(3) spores/ml after 35 and 20 days incubation. There was no spore concentration influence on zearalenone and deoxynivalenol production after 10, 20 and 35 days incubation. At 28°C and 0.97 water activity (aw), the mean levels of zearalenone production were 382, 267 and 520 µg/kg and the mean levels on deoxynivalenol production were 697,465 and 782 µg/kg.