title: Bioavailability and metabolism of orange juice flavanones in humans: impact of a full-fat yogurt.
abstract: The bioavailability of dietary phytochemicals may be influenced by the food matrix in which they are consumed. In this study the impact of a full-fat yogurt on the bioavailability and metabolism of orange juice flavanones was investigated. Human plasma and urine were collected over a 24 h period after the consumption of 250 mL of orange juice containing a total of 168 micromol of hesperetin-7-O-rutinoside and 12 micromol of naringenin-7-O-rutinoside, with and without 150 mL of full-fat yogurt. The juice also contained 1 g of paracetamol and 5 g of lactulose. HPLC-MS(2) analysis revealed the accumulation of hesperetin-7-O-glucuronide, and an unassigned hesperetin-O-glucuronide metabolite in plasma reached a peak concentration (C(max)) of 924 +/- 224 nmol/L, 4.4 +/- 0.5 h (T(max)) after orange juice ingestion. The T(max) is indicative of absorption in the colon. When the juice was consumed with yogurt, neither the C(max) at 661 +/- 170 nmol/L nor the T(max) at 5.1 +/- 0.4 h were significantly different from those obtained with juice alone. The two hesperetin glucuronides were also excreted in urine along with a third hesperetin-O-glucuronide, two hesperetin-O-glucuronide-O-sulfates, a hesperetin-O-diglucuronide, a naringenin-O-diglucuronide, and, tentatively identified, naringenin-7-O-glucuronide and naringenin-4'-O-glucuronide. This indicates the occurrence of substantial, postabsorption, phase II metabolism prior to urinary excretion. The quantity of flavanone metabolites excreted 0-5 h after orange juice ingestion was significantly reduced by yogurt, but over the full 0-24 h urine collection period, the amounts excreted, corresponding to ca. 7.0% of intake, were not affected by the addition of yogurt to the drink. Nor did yogurt have a significant effect on gastric emptying, as determined by plasma paracetamol levels, or on the mouth to cecum transit time of the head of the meal, assessed by measurement of lactulose-derived breath hydrogen. There is also a discussion of the merits of studies of the absorption and metabolism of flavanones based on direct analysis of metabolites by HPLC-MS and the more traditional indirect approach where samples are treated with a mollusc glucuronidase/sulfatase preparation prior to HPLC analysis of the released aglycones.
authors.affiliation: University of Glasgow, United Kingdom.
authors.forename: William
authors.initials: W
authors.lastname: Mullen
authors.forename: Marie-Amelie
authors.initials: MA
authors.lastname: Archeveque
authors.forename: Christine A
authors.initials: CA
authors.lastname: Edwards
authors.forename: Hikaru
authors.initials: H
authors.lastname: Matsumoto
authors.forename: Alan
authors.initials: A
authors.lastname: Crozier
mesh_terms: D000328:Adult; D000818:Animals; D001628:Beverages / Q000032:analysis*; D001682:Biological Availability; D002957:Citrus / Q000737:chemistry / Q000378:metabolism*; D005260:Female; D044950:Flavanones / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D020719:Glucuronides / Q000493:pharmacokinetics* / Q000652:urine; D006569:Hesperidin / Q000031:analogs & derivatives* / Q000493:pharmacokinetics / Q000652:urine; D006801:Humans; D008297:Male; D008875:Middle Aged; D015014:Yogurt / Q000032:analysis*; D055815:Young Adult
chemical_list: D044950:Flavanones; D020719:Glucuronides; C587870:hesperetin-7-O-glucuronide; D006569:Hesperidin