Fungus and mycotoxins in wheat grain at post harvest.

The aim of this work was to assess the fungus and mycotoxins contamination in wheat grain (Triticum aestivum) in post harvest during 180 days of storage. Five samples were taken at 30 days intervals during the six months of storage period, assessing fungus such as: Aspergillus spp., Penicillium spp. and Fusarium spp., and mycotoxins such as aflatoxins (AFB1, AFB2 and AFG1, AFG2), ochratoxin A (OTA), zearalenone (ZON), deoxinivalenol (DON) and fumonisins (FB1 and FB2). The results showed that in all 35 samples analyzed many mycotoxins such as aflatoxins, ochratoxin A, zearalenone, deoxinivalenol and fumonisin FB2 were detected and the fumonisin FB1 were present in 11 samples (31.4 %) with levels of 36.3 to 2,891 mg/g. The presence of the Aspergillus spp., fungus showed in 100 % of the samples, the Fusarium spp. in 80 %, and Penicillium spp. in 60 % of the samples. The influence of grain fumigation during the storage period on the microorganism development, by reducing the percentage of fungus in the grain bulk, was also verified. This was due to the deleterious effect of phosphine on fungus development. As the mycotoxins can not be removed from the grain during milling process it is important to prevent their development by reducing the temperature and moisture content, and also the pest contamination in the bulk grain. Key words: Mycotoxins, storage grain, fungus, wheat quality.