BIOSYNTHESIS OF VERSICONAL ACETATE, VERSICONOL ACETATE, AND VERSICONOL, METABOLITES FROM CULTURES OF ASPERGILLUS-PARASITICUS TREATED WITH DICHLORVOS - ROLE OF VERSICONAL ACETATE IN AFLATOXIN BIOSYNTHESIS

The biosynthesis of versiconal acetate, versiconol acetate, and versiconol, metabolites isolated from cultures of Aspergillus 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.