Interaction of water activity and temperature on aflatoxin production by Aspergillus flavus and A. parasiticus in irradiated maize seeds

Abstract

The effects of a _w (0.90, 0.95, 0.98) and temperature (25°C, 30°C, 35°C) on aflatoxin production by Aspergillus flavus and Aspergillus parasiticus growing on irradiated maize seeds, were examined. Highest levels of aflatoxin were produced by A. parasitious at 25°C and 0.98 a _w and by A. flavus at 30°C at 0.95 and 0.98 a _w. At 0.90 a _w toxin production was consistently low for both species at all temperatures. Temperature cycling of A. flavus between 25°C and 35°C each for 12 h resulted in higher aflatoxin synthesis than when incubated either at 25°C or 35°C.

Keywords:

• Aspergillus
• mycotoxin
• aflatoxin
• maize