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

Fumonisin B1 (FB1) is a mycotoxin from Fusarium moniliforme that is fr equently associated with corn. Thermal treatments are used in many pro cesses 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 t wo-step sequential development and postchromatographic derivatization by p-anisaldehyde. The identity of FB1 in extracts, before and after h eat 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 ti me. The calculated half-lives (L50), corresponding to the 50% value, w ere 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 L50 s on a logarithmic scale and temperature. Therefore FB1 is not signifi cantly destroyed by the main drying processes of corn or thermal treat ments used for its derivatives. Other associated means are required fo r detoxification.