Identification of Fusarium verticillioides fumonisin B1 mycotoxin and the effects of pH, relative humidity and light on its production on maize substrate

Fusarium verticillioides is one of the most important and potent fungi producing fumonisins and causes major damage to agricultural products and adverse health effects on comcumers. The production of these toxins is greatly influenced by environmental factors. In this study, the effect of environmental factors, including light duration (0, 12 and 24 h), seed moisture content (15, 18, 25, 23, 25, 28 and 30%) and pH (4, 5, 6 and 7) were evaluated on fumonisin B1 production. Towards this aim, fungal isolates were recovered from corn fields showing signs and symptoms of infection and were subjected to morphological identifiction. Fumonisin B1 was extracted using acetonitrile, methanol, cationic resin, alumina carbon, and then detected by TLC and HPLC methodes.The identity of the isolates was determined as F. verticillioides. The results of HPLC analysis showed that the amount of fumonisin B1 produced by F. verticillioides in different treatments ranged from 200 ng/ml to 520 ng/ml. The highests amount of fumonisin B1 including 424 ng/ml, 422 ng/ml and 520 ng/ml were produced in 28% corn seed moister pH: 4 and 24 hours-light treatment, respectively. Therefore, by controlling the environmental conditions in seed storage and silo, the production of fumonisins can be minimized.