Structural Elucidation of T-2 Toxin Thermal Degradation Products and Investigations toward Their Occurrence in Retail Food

The stability of T-2 toxin under the conditions of baking or cooking was investigated using heating experiments with the model substances alpha-D-glucose, alpha-D-methyl-glucopyranosid, N-alpha-acetyl-L-lysine methyl ester, and N-alpha-acetyl-cysteine methyl ester. The reaction residue was screened for degradation products using gas chromatography-mass spectrometry (GC-MS) and high-performance liquid chromatography with evaporative light-scattering detection (HPLC-ELSD). Although T-2 toxin was degraded under all conditions, only heating of T-2 toxin with a-D-glucose produced a mixture of three degradation products, which were isolated and identified by MS and nuclear magnetic resonance (NMR) experiments. The reaction mechanism for the formation of the T-2 degradation products was elucidated by quantum chemical calculations. The relevance of these degradation products was investigated by baking experiments as well as the analysis of retail food samples. In cell-culture studies using immortalized human kidney epithelial (IHKE) cells, the T-2 degradation products were less cytotoxic (formazan dye cytotoxicity assay) compared to T-2 toxin.