Biosynthesis of versiconal acetate, versiconol acetate, and versiconol, metabolites from cultures of Aspergillus parasiticus treated with dichlorvos. The role of versiconal acetate in aflatoxin biosynthesis

Abstract

The biosynthesis of versiconal acetate, versiconol acetate, and versiconol, metabolites isolated from cultures of Aspergillius parasiticus which had been treated with the insecticide dichlorvos, was studied by ¹³C n.m.r. spectroscopy. The distribution of ¹³C label and the arrangement of intact acetate units in the three metabolites derived from [1-¹³C]- and [1,2-¹³C]-acetate, respectively is in accord with their origin from a single C₂₀ polyketide precursor. The significance of versiconal acetate in the biosynthesis of aflatoxin B₁ is outlined.