April 5, 2024
Reading Time: 2 minutes
The global trading of wheat and its subsequent transportation leads to increased storage time of the grains, which can be at risk for mycotoxins. In their study, Wang et al. simulated different storage conditions (time, temperature, humidity, initial mycotoxin load) and evaluated their effects on fungal communities and mycotoxin contamination, with a focus on deoxynivalenol (DON) and its masked form D3G.
As expected, independently of storage conditions, the results show that typical field fungi (Alternaria, Fusarium) were gradually replaced by storage fungi (Aspergillus mainly), though Fusarium first increased, before decreasing until total inhibition.
DON contamination significantly evolved during storage. In the first month of storage, DON level increased by about 14% in all storage conditions. A longer storage had different effects on DON level in the wheat: at 25°C, the level increased by 36% while it decreased at 30 and 35°C. The change in moisture also stressed DON production: 12% and 15% relative humidity (RH) increased DON levels by circa 67% compared to the 13% RH storage. The D3G level was highly associated with DON level (D3G being converted from DON) and increased by up to 202% in specific conditions (linked with insect presence for example).
Figure: Changes in deoxynivalenol (DON) content in wheat under different storage conditions. Adapted from Wang et al.
In general, the study indicates that the storage conditions and the initial DON load significantly influence the mycotoxin-producing Fusarium taxa and change the DON and D3G content. This seems to be correlated with the competition between fungi: the more the competition, the higher the DON production.
Reference: Wang R., Mengmeng L., Jin R., Liu Y., Guan E., Mohamed S.R., Bian K. Interactions among the composition changes in fungal communities and the main mycotoxins in simulated stored wheat grains. J Sci Food Agric 2024, 104, 373-382. https://doi.org/10.1002/jsfa.12928
