Simultaneous high-performance liquid chromatographic determination of visoltricin, acuminatopyrone and chlamydosporols in Fusarium cultures on maize

Visoltricin (VIS), acuminatopyrone (ACP), clamydosporol (CL), isochlamydosporol (ICL) and chlamydospordiol (DIOL), recently characterized Fusarium metabolites, were separated on a polymeric RP-18 column eluted with acetonitrile-0.01% ammonia solution (35:65) at 1 ml/min and detected with a diode-array UV detector. The presence of ammonia in the mobile phase improved the shape of the CL and VIS peaks. The use of a polymeric column was required owing to the basic pH of the mobile phase. Maize cultures of several strains of F. tricinctum and F. chlamydosporum were analysed with this procedure after extraction with aqueous methanol, partitioning with methylene chloride and clean-up with a C₁₈ minicolumn. VIS was produced only by F. tricinctum, whereas ACP and chlamydosporols were produced by both Fusarium species.