Polyphenols from Alcoholic Apple Cider Are Absorbed, Metabolized and Excreted by Humans

• Published in: The Journal of nutrition Vol. 132; no. 2; pp. 172 - 175
• Main Authors: DuPont, M. Susan, Bennett, Richard N., Mellon, Fred A., Williamson, Gary
• Format: Journal Article
• Language: English
• Published: Bethesda, MD Elsevier Inc 01.02.2002; American Society for Nutritional Sciences; American Institute of Nutrition
• Subjects: Absorption; Adult; Alcohol use; Alcoholic Beverages; apple cider; Apples; beverages; Biological and medical sciences; blood; caffeic acid; Caffeic Acids; Caffeic Acids - blood; Caffeic Acids - pharmacokinetics; Caffeic Acids - urine; chemistry; Chromatography, High Pressure Liquid; cider; detection limit; esters; Female; Flavonoids; Hippurates; Hippurates - blood; Hippurates - pharmacokinetics; Hippurates - urine; hippuric acid; Humans; Male; Malus; Malus - chemistry; Metabolism; Methylation; pharmacokinetics; Phenols; Phenols - blood; Phenols - metabolism; Phenols - urine; Phloretin; Phloretin - blood; Phloretin - urine; Plasma; Polymers; Polymers - metabolism; polyphenol; polyphenols; quercetin; Quercetin - blood; Quercetin - pharmacokinetics; Quercetin - urine; urine; phloretin; quercetin; flavonoids; polyphenol; cider
• DOI: 10.1093/jn/132.2.172
• ISSN: 0022-3166

We determined the uptake and excretion of low doses of polyphenols in six subjects who each consumed 1.1 L of an alcoholic cider beverage. Over a 24-h period, no phloretin was detected in plasma (detection limit = 0.036 μmol/L), but 21 ± 5% of the dose (4.8 mg) was excreted in the urine. In contrast, from a low dose of 1.6-mg quercetin equivalents, no quercetin was found in urine or plasma, but 3′-methyl quercetin was detected in plasma [Cmax (maximum concentration) = 0.14 ± 0.19 μmol/L; range: 0 to 0.44 μmol/L]. No flavanol monomers (dose of free (+)-catechin and (−)-epicatechin = 3.5 mg) were detected in urine or plasma (detection limit: 0.01 μmol/L). Caffeic acid (total dose including esters = 11 mg) was detected only in plasma within 2 h, with Cmax = 0.43 ± 0.3 μmol/L (range: 0.18 to 0.84 μmol/L). An almost 3-fold increase in hippuric acid was detected in 24-h urine (74 ± 29 μmol/L; range: 38–116 μmol/L), compared with a prestudy value of 19 ± 9 μmol/L. These data show that polyphenols are taken up from cider, that phloretin is excreted in the urine and suggest that low doses of quercetin are extensively methylated in humans.