title: Faecal microbial metabolism of olive oil phenolic compounds: in vitro and in vivo approaches.
abstract: METHODS
  In the present study, the individual colonic metabolism of the main components of the virgin olive oil phenolic fraction was evaluated by an in vitro model using human faecal microbiota. To assess differences in metabolism related to the molecular structure, four phenolic standards were selected, tyrosol, hydroxytyrosol, hydroxytyrosol acetate and oleuropein. After studying the in vitro colonic metabolism pathways of the individual phenols, the presence of their colonic metabolites was investigated in human faecal samples obtained before and after the sustained intake (3 weeks) of a daily dose of 25 mL of a phenol-enriched olive oil.
  
  
  RESULTS
  The in vitro colon fermentation of the four individual phenolic compounds revealed (i) an increase in phenolic acids, (ii) the stability of hydroxytyrosol and tyrosol and (iii) the high degradation of hydroxytyrosol acetate and oleuropein. Additionally, a moderate intake of a phenol-rich olive oil raised the concentration in human faeces of free hydroxytyrosol and phenylacetic and phenylpropionic acids.
  
  
  CONCLUSIONS
  The products of colonic catabolism of olive oil phenolic compounds could be good candidates for novel preventive strategies and open a promising line of research into the preventive action of olive oil phenols in colon and other bowel diseases.
authors.affiliation: Food Technology Department, UTPV-XaRTA, Agrotecnio Center, University of Lleida, Lleida, Spain.
authors.forename: Juana I
authors.initials: JI
authors.lastname: Mosele
authors.forename: Sandra
authors.initials: S
authors.lastname: Martín-Peláez
authors.forename: Alba
authors.initials: A
authors.lastname: Macià
authors.forename: Marta
authors.initials: M
authors.lastname: Farràs
authors.forename: Rosa-Maria
authors.initials: RM
authors.lastname: Valls
authors.forename: Úrsula
authors.initials: Ú
authors.lastname: Catalán
authors.forename: María-José
authors.initials: MJ
authors.lastname: Motilva
mesh_terms: D000085:Acetates / Q000378:metabolism / Q000493:pharmacokinetics; D002396:Catechols / Q000378:metabolism / Q000493:pharmacokinetics; D003106:Colon / Q000378:metabolism; D005243:Feces / Q000382:microbiology*; D005285:Fermentation; D006801:Humans; D066298:In Vitro Techniques; D057888:Iridoid Glucosides; D039823:Iridoids / Q000378:metabolism / Q000493:pharmacokinetics; D007700:Kinetics; D064307:Microbiota / Q000502:physiology; D033281:Nontherapeutic Human Experimentation; D000069463:Olive Oil; D010636:Phenols / Q000378:metabolism* / Q000493:pharmacokinetics; D010626:Phenylethyl Alcohol / Q000031:analogs & derivatives / Q000378:metabolism / Q000493:pharmacokinetics; D010938:Plant Oils / Q000737:chemistry* / Q000494:pharmacology
chemical_list: D000085:Acetates; D002396:Catechols; D057888:Iridoid Glucosides; D039823:Iridoids; D000069463:Olive Oil; D010636:Phenols; D010938:Plant Oils; C524604:hydroxytyrosyl acetate; C005975:3,4-dihydroxyphenylethanol; C011867:4-hydroxyphenylethanol; C002769:oleuropein; D010626:Phenylethyl Alcohol
keywords: Faecal microbial metabolism; Gut phenolic metabolites; Hydroxytyrosol; Metabolic pathways; Olive oil phenolic compounds