Urinary conversion products of certain orally administered isoflavones in the fowl

Abstract

Synthetic 5,7-dihydroxy-4′-methoxy[4- 14C]isoflavone ([4[ 14C]biochanin A) was administered orally to a non-laying hen. The urine subsequently excreted contained radioactive biochanin A and radioactive 4′,5,7-trihydroxyisoflavone. Chromatographic evidence indicated the presence also of a minute proportion of radioactive 7-hydroxy-3(4′-hydroxyphenyl)-chroman (equol). Synthetic 7-hydorxy-4′-methoxy[4- 14C]isoflavine ([4- 14C]formononetin)_was administered orally to a non-laying hen. The urine excreted contained the following radioactive substances: formonoentin: 4′,7-dihydroxyisoflavone (daidzein); 2,4-dihydroxyphenyl- p-methoxybenzyl ketone; 2,4-dihydroxyphenyl- p-hydrozybenzyl ketone; and equol. Equol accounted for 65% of the radioactivity recovered in the semipurified urinary phenolic fraction. Synthetic [4- 14C]daidzein was administered orally to a non-laying hen. The urine excreted contained the following radioactive substances: daidzein; 2,4-dihydroxyphenyl- p-dihydroxybenzyl ketone; and equol. The equol accounted for 70% of the radioactivity recovered in the semi-purified phenolic fraction.