PRODUCTION OF TYPE-A TRICHOTHECENES AND ENNIATIN-B BY FUSARIUM-SAMBUCINUM FUCKEL SENSU-LATO

Twenty-nine Fusarium isolates, representing three new taxa originated by Nirenberg from F. sambucinum Fuckel sensu lato, namely: F. sambucin um Fuckel sensu stricto, F. venenotum Nirenb., and F. torulosum (Perk. and Curt.) Nirenb., were tested for in vitro production of toxic seco ndary metabolites on autoclaved corn kernels. F. sambucinum sensu stri cto was able to produce type A trichothecenes and enniatin B (EB). In particular, amongst the 14 isolates tested, 5 produced only diacetoxys cirpenol (DAS) (up to 700 mu g/g); 1 produced only neosolaniol (NEOS) (250 mu g/g); 2 produced T-2 toxin (T-2) + NEOS (up to 175 and 150 mu g/g, respectively); 1 produced NEOS + DAS (300 and 100 mu g/g, respect ively); and 5 produced DAS + EB (up to 500 and 140 mu g/g, respectivel y). All six isolates of F. venenotum were able to produce only DAS (up to 100 mu g/g). F. torulosum produced no trichothecenes, but four out of nine tested isolates were able to produce EP (up to 140 mu g/g). Z earalenones and type B trichothecenes were not found. The toxicity of the culture extracts towards Artemia salina L. was correlated in gener al with the occurrence of the above toxins, except for some F. torulos um strains. However, the lack of correlation between the amounts of to xins recovered and toxic activity observed in the Geotrichum candidum Link ex Pers. and A. salina assays suggested the presence of unknown t oxic compounds.