LIQUID-CHROMATOGRAPHIC DETERMINATION OF MAJOR SECONDARY METABOLITES PRODUCED BY ASPERGILLUS SPECIES FROM SECTION FLAVI

A liquid chromatographic (LC) method was developed for simultaneous de termination of major secondary metabolites-including cyclopiazonic aci d (CPA), O-methylsterigmatocystin (OMST), and the versicolorins-produc ed by Aspergillus species from section Flavi (A. flavus, A. parasiticu s, A. tamarii, and A. caelatus) on a liquid medium. Metabolites were e xtracted with chloroform and quantitated without prior cleanup by mean s of normal-phase ion-pair partition LC on silica gel with a mobile ph ase of tane-2-propanol-n-butanol-water-tetrabutylammonium hydroxide (2 560 + 900 + 230 + 32 + 8, v/v). Recoveries of CPA and OMST from fungal cultures spiked at 10 mu g/mL were 98.90 +/- 3.27 and 95.92 +/- 5.27% (n = 5), respectively. At spike levels of 100 mu g/mL, recoveries wer e 98.89 +/- 3.87 and 97.65 +/- 4.32% (n = 5), respectively. Limits of detection for pure standards were 0.25 mu g/mL for CPA (at 280 nm) and 0.30 mu g/mL for OMST (at 310 nm). UV detector responses to CPA and O MST were linear to about 0.5 and 3.5 mu g/injection, respectively.