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The mycotoxins diacetoxyscirpenol, deoxynivalenol, and zearalenone, produced by Fusarium roseum, were found naturally occurring in mixed feed samples. In all cases analyzed, deoxynivalenol occurred together with zearalenone. The natural occurrence of zearalenone in sesame seed is reported for the first time. Strains of F. roseum isolated in various parts of the world from feed implicated in animal mycotoxicosis produced monoacetoxyscirpenol, diacetoxyscirpenol, deoxynivalenol, and zearalenone.

One diastereomer of trans-zearalenol [2,4-dihydroxy-6-(6,10-dihydroxy-trans-1-undecenyl)-benzoic acid-y-lactone] was isolated from cultures of Fusarium roseum 'Gibbosum.' This strongly estrogenic metabolite was identified by analysis of its mass spectrum and its behavior in thin-layer, high-pressure liquid and gasliquid chromatographic systems. The concentration of zearalenol in cultures was 563 ,ug/g, or 7% of the 8,000-,ug/g zearalenone content, while the two diastereomers

Tritium-labeled T-2 toxin [4~,15-diacetoxy,8a-(3-methylbutyryloxy)-3a-hydroxy-12,13-epoxytrichothec-g-ene] was synthesized using a two-step process. First, the C-3 hydroxyl was oxidized to a ketone using either chromium trioxide-pyridine or dimethyl sulfide-N-chlorosuccinimide complex. In step two, the ketone was reduced with either tritiated sodium cyanoborohydride or tritiated sodium borohydride to a mixture of epimers which were separable by thin-layer chromatography. The a epimer (naturally occurring T-2 toxin) was formed predominantly, i.e., a to ratio was 4 to 1. Final reduction with tritiated sodium borohydride yielded [3-3H]T-2 toxin in 23% yield with a specific activity of 790 mCi/mmol. The labeled product, when equilibrated with 0.01 N HC1, did not lose the tritium, indicating that no labile tritium was incorporated into T-2 toxin. Further, the oxidation of [3-3H]T-2 toxin resulted in total loss of activity in the corresponding ketone.The metabolites of species of Fusarium are commonly found in foodstuff and are prominent because of their association with cases of mycotoxicoses of humans and animals. One such metabolite, T-2 toxin (1) [4&15-diacetoxy,8a-( 3-methylbutyryloxy)-3a-hydroxy-12,13-epoxytrichothec-g-ene] has been implicated as a mycotoxin responsible for the hemorrhagic syndrome and death of dairy cattle (Hsu et al., 1972). T-2 toxin causes an extreme dermal necrosis in most animals and is also one of the most

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