Metabolism of aromatic plant ketones in rats: acetovanillone and paeonol.
1. The metabolism of the plant ketones acetovanillone (4-hydroxy-3-methoxyacetophenone) and paeonol (2-hydroxy-4-methoxyacetophenone), was studied in rats. Identification and quantification of metabolites was carried out by g.l.c.-mass spectometry and g.l.c., respectively, following intragastric doses of 1 mmol/kg. 2. Acetovanillone was rapidly excreted in the urine, mainly unchanged but also as the demethylated compound and three ring-hydroxylated metabolites. Minor additional metabolic pathways produced the para-methoxy derivative, acetoisovanillone, a dimethoxy-hydroxy derivative and two 1-phenylethanol derivatives formed by ketone reduction of acetovanillone and 3,4-dihydroxyacetophenone. 3. Paeonol was metabolized more extensively and larger amounts of the demethylated (resacetophenone) and hydroxylated (mainly 2,5-dihydroxy-4-methoxyacetophenone and a trihydroxyacetophenone) metabolites were excreted. Paeonol was not found to undergo ketone reduction, however, small amounts of the hydroxymethyl derivative formed by omega-oxidation were detected. 4. The metabolites were excreted mainly as glucuronide and/or sulphate conjugates. Faecal recoveries of metabolites were very small and the urinary excretion (48 h) was 97% (acetovanillone) and 61% (paeonol).
Gjertsen
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FB
Department of Pharmacology and Toxicology, School of Medicine, University of Bergen, Norway.
Solheim
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E
Scheline
R R
RR
D000098:Acetophenones / Q000493:pharmacokinetics*; D000818:Animals; D005243:Feces / Q000032:analysis; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
D000098:Acetophenones; C013638:paeonol; C056165:acetovanillone