THERMOSTABILITY OF FUMONISIN-B1, A MYCOTOXIN FROM FUSARIUM-MONILIFORME, IN CORN

Fumonisin B1 (FB1) is a mycotoxin from Fusarium moniliforme that is frequently associated with corn. Thermal treatments are used in many processes concerning this cereal and its derivatives. The thermostability of this toxin in dry contaminated corn, resulting from F. moniliforme culture, was studied in different time-temperature combinations. FB1 was quantified by instrumentalized thin-layer chromatography after a two-step sequential development and postchromatographic derivatization by p-anisaldehyde. The identity of FB1 in extracts, before and after heat treatments, was confirmed by high-pressure liquid chromatography. For each temperature, the natural logarithm of the ratio of resulting FB1 on initial content (ln C/C0) is linearly correlated to exposure time. The calculated half-lives (L50), corresponding to the 50% value, were 10 min, 38 min, 175 min, and 8 h at 150, 125, 100, and 75-degrees-C, respectively. There is a linear relationship between calculated L50s on a logarithmic scale and temperature. Therefore FB1 is not significantly destroyed by the main drying processes of corn or thermal treatments used for its derivatives. Other associated means are required for detoxification.