title: Human metabolism and elimination of the anthocyanin, cyanidin-3-glucoside: a (13)C-tracer study.
abstract: BACKGROUND
  Evidence suggests that the consumption of anthocyanin-rich foods beneficially affects cardiovascular health; however, the absorption, distribution, metabolism, and elimination (ADME) of anthocyanin-rich foods are relatively unknown.
  
  
  OBJECTIVE
  We investigated the ADME of a (13)C5-labeled anthocyanin in humans.
  
  
  METHODS
  Eight male participants consumed 500 mg isotopically labeled cyanidin-3-glucoside (6,8,10,3',5'-(13)C5-C3G). Biological samples were collected over 48 h, and (13)C and (13)C-labeled metabolite concentrations were measured by using isotope-ratio mass spectrometry and liquid chromatography-tandem mass spectrometry.
  
  
  RESULTS
  The mean ± SE percentage of (13)C recovered in urine, breath, and feces was 43.9 ± 25.9% (range: 15.1-99.3% across participants). The relative bioavailability was 12.38 ± 1.38% (5.37 ± 0.67% excreted in urine and 6.91 ± 1.59% in breath). Maximum rates of (13)C elimination were achieved 30 min after ingestion (32.53 ± 14.24 μg(13)C/h), whereas (13)C-labeled metabolites peaked (maximum serum concentration: 5.97 ± 2.14 μmol/L) at 10.25 ± 4.14 h. The half-life for (13)C-labeled metabolites ranged between 12.44 ± 4.22 and 51.62 ± 22.55 h. (13)C elimination was greatest between 0 and 1 h for urine (90.30 ± 15.28 μg/h), at 6 h for breath (132.87 ± 32.23 μg/h), and between 6 and 24 h for feces (557.28 ± 247.88 μg/h), whereas the highest concentrations of (13)C-labeled metabolites were identified in urine (10.77 ± 4.52 μmol/L) and fecal samples (43.16 ± 18.00 μmol/L) collected between 6 and 24 h. Metabolites were identified as degradation products, phenolic, hippuric, phenylacetic, and phenylpropenoic acids.
  
  
  CONCLUSIONS
  Anthocyanins are more bioavailable than previously perceived, and their metabolites are present in the circulation for ≤48 h after ingestion. This trial was registered at clinicaltrials.gov as NCT01106729.
authors.affiliation: Department of Nutrition, Norwich Medical School, University of East Anglia, Norwich, United Kingdom.
authors.forename: Charles
authors.initials: C
authors.lastname: Czank
authors.forename: Aedín
authors.initials: A
authors.lastname: Cassidy
authors.forename: Qingzhi
authors.initials: Q
authors.lastname: Zhang
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Morrison
authors.forename: Tom
authors.initials: T
authors.lastname: Preston
authors.forename: Paul A
authors.initials: PA
authors.lastname: Kroon
authors.forename: Nigel P
authors.initials: NP
authors.lastname: Botting
authors.forename: Colin D
authors.initials: CD
authors.lastname: Kay
mesh_terms: D000042:Absorption; D000284:Administration, Oral; D000328:Adult; D000872:Anthocyanins / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D001682:Biological Availability; D015992:Body Mass Index; D002851:Chromatography, High Pressure Liquid / Q000379:methods; D002149:Energy Intake; D005243:Feces / Q000737:chemistry; D005500:Follow-Up Studies; D005960:Glucosides / Q000008:administration & dosage* / Q000097:blood / Q000493:pharmacokinetics* / Q000652:urine; D006207:Half-Life; D006801:Humans; D007553:Isotope Labeling / Q000379:methods; D008297:Male; D013058:Mass Spectrometry / Q000379:methods; D055815:Young Adult
chemical_list: D000872:Anthocyanins; D005960:Glucosides; C462279:cyanidin-3-O-beta-glucopyranoside