NATURAL OCCURRENCE OF BEAUVERICIN IN PREHARVEST FUSARIUM-SUBGLUTINANSINFECTED CORN EARS IN POLAND

Fourteen samples of preharvest infected corn ears, collected in 1990-1 991 from different Polish cornfields, were found to be highly infected by Fusarium subglutinans. This species was recently shown to produce in culture beauvericin (BEA), a toxin mostly known for its insecticida l properties. Chemical analysis by high-performance liquid chromatogra phy and high-performance thin-layer chromatography revealed the occurr ence in the naturally infected corn samples of BEA (up to 60 mg/kg). W hen cultured on autoclaved corn kernels for 4 weeks at 25-degrees-C 8 of the 10 assayed strains of F. subglutinans produced BEA (up to 200 m g/kg), whereas 9 strains also produced moniliformin (up to 500 mg/kg). Cultural extracts containing the highest amounts of BEA proved to be toxic in Artemia salina bioassay. The natural occurrence of BEA in cor n is reported here for the first time.