Mutual effects on mycotoxin production during co-culture of ochratoxigenic and aflatoxigenic Aspergillus strains

AbstractMycotoxin co-occurrence compromises the safety of food crops worldwide. Environmental factors, as well as fungal interaction, can substantially influence the infectivity of mycotoxigenic fungi and their subsequent production of multi-mycotoxin. Here, we investigated the mutual effects of the co-culture of ochratoxigenic and aflatoxigenicAspergillus strains on the co-production of ochratoxin A (OTA) and aflatoxin B1 (AFB1). Single cultures of ochratoxigenicA. carbonarius andA. alliaceus grew optimally at 25  °C, whereas aflatoxigenicA. flavus grew optimally at 35  °C. The maximum levels of OTA and AFB1 were achieved at 25 °C, whereas mycotoxin production decreased at 35 °C. During competitive growth of the ochratoxigenic and aflatoxigenic isolates, inhibition or stimulation of mycotoxin production was dependent on the fungal strain, temperature, and th e ratio of the spore concentration.Aspergillus carbonarius andA. alliaceus generally produced OTA, with similar patterns of relative OTA levels at all temperatures. AFB1 production byA. flavus in the presence of ochratoxigenicAspergillus species was inhibited at 25  °C and stimulated at 35 °C. These results indicated that the temperature, presence of other mycotoxigenicAspergillus species, and ratio of the initial spore concentration significantly contributed to the co-production of OTA and AFB1.
Source: Mycotoxin Research - Category: Toxicology Source Type: research