title: Urinary metabolite profiling identifies novel colonic metabolites and conjugates of phenolics in healthy volunteers.
abstract: METHODS
  The colonic metabolism of dietary flavonoids, phenolic acids and their phenolic metabolites is complex and many metabolites and conjugates have not yet been unambiguously identified in humans.
  
  
  RESULTS
  Urine samples from nine healthy human volunteers obtained after the ingestion of a puree of five (poly)phenol-rich berry fruits were analysed using LC-Orbitrap MS to provide a preliminary indication of possible metabolites based on exact mass. In most cases, the identity of compounds was confirmed using standards produced either chemically or enzymically followed by analysis using LC-triple quadrupole MS. Sulphated, glucuronidated and methylated forms of catechol, pyrogallol and protocatechuic acid mostly appeared in urine after 8 h, suggesting colonic metabolism. Gallic acid and (-)-epicatechin conjugates appeared mainly before 4 h, indicative of absorption from the small intestine. Conjugates of ferulic, caffeic, and vanillic acid appeared at intermediate times.
  
  
  CONCLUSIONS
  We have positively identified metabolites and conjugates, some novel, in the urine of healthy volunteers after intake of multiple phenolics from a mixed puree from berry fruits, with each being excreted at specific and signature times. Some of these compounds could potentially be used as biomarkers of fruit intake. The possible biological activities of these colonic metabolites require further assessment.
authors.affiliation: Instituto de Tecnologia Química e Biológica, Universidade Nova de Lisboa, Av. da República, EAN, Oeiras, Portugal.
authors.forename: Rui C
authors.initials: RC
authors.lastname: Pimpão
authors.forename: Tristan
authors.initials: T
authors.lastname: Dew
authors.forename: Maria E
authors.initials: ME
authors.lastname: Figueira
authors.forename: Gordon J
authors.initials: GJ
authors.lastname: McDougall
authors.forename: Derek
authors.initials: D
authors.lastname: Stewart
authors.forename: Ricardo B
authors.initials: RB
authors.lastname: Ferreira
authors.forename: Claudia N
authors.initials: CN
authors.lastname: Santos
authors.forename: Gary
authors.initials: G
authors.lastname: Williamson
mesh_terms: D000328:Adult; D000410:Alanine Transaminase / Q000097:blood; D001219:Aspartate Aminotransferases / Q000097:blood; D015415:Biomarkers / Q000652:urine; D001786:Blood Glucose / Q000378:metabolism; D029798:Blueberry Plants / Q000737:chemistry; D015992:Body Mass Index; D002392:Catechin / Q000652:urine; D008076:Cholesterol, HDL / Q000097:blood; D008078:Cholesterol, LDL / Q000097:blood; D002853:Chromatography, Liquid; D003106:Colon / Q000378:metabolism*; D003404:Creatinine / Q000097:blood; D005260:Female; D031985:Fragaria / Q000737:chemistry; D005638:Fruit / Q000737:chemistry*; D005707:Gallic Acid / Q000652:urine; D064368:Healthy Volunteers; D006801:Humans; D008297:Male; D008875:Middle Aged; D059808:Polyphenols / Q000378:metabolism* / Q000652:urine*; D065856:Rubus / Q000737:chemistry; D011795:Surveys and Questionnaires; D053719:Tandem Mass Spectrometry; D014280:Triglycerides / Q000097:blood; D055815:Young Adult; D005723:gamma-Glutamyltransferase / Q000097:blood
chemical_list: D015415:Biomarkers; D001786:Blood Glucose; D008076:Cholesterol, HDL; D008078:Cholesterol, LDL; D059808:Polyphenols; D014280:Triglycerides; D005707:Gallic Acid; D002392:Catechin; D003404:Creatinine; D005723:gamma-Glutamyltransferase; D001219:Aspartate Aminotransferases; D000410:Alanine Transaminase
keywords: Berry fruits; Bioavailability; Colon; Conjugates; Metabolomics