TRICHODIENE AS A VOLATILE MARKER FOR TRICHOTHECENES BIOSYNTHESIS

The ability of Fusarium strains, belonging to five different species, to produce volatile compounds and trichothecene toxins was monitored b y gas chromatography/mass spectrometry (GC/MS). Isolates were grown fo r 21 days on autoclaved wheat kernels. The volatiles were collected af ter three and 21 days on Tenax GR traps using a dynamic headspace meth od, and immediately after volatiles collection the cultures were check ed for trichothecenes presence. Of nine analyzed strains, seven were t oxigenic and produced trichothecenes of both A and B type. Among volat ile metabolites sesquiterpene hydrocarbon trichodiene was the object o f interest as the intermediate in biosynthesis of all trichothecenes. It was produced exclusively by toxigenic strains representing four spe cies, that produced ten different toxins. Trichodiene was detected in all toxigenic strains after three days of incubation, in two cases bef ore any toxins were observed. Trichodiene presence determined by a dyn amic headspace method can serve as an indicator for undergoing trichot hecene toxins biosynthesis. (C) 1997 Elsevier Science B.V.