In vitro metabolism of anthocyanins by human gut microflora
Rent the article at a discountRent now
* Final gross prices may vary according to local VAT.Get Access
Only a small part of the dietary anthocyanins are absorbed. Thus large amounts of the ingested compounds are likely to enter the colon. In vitro and in vivo studies have shown that colonic bacteria transform various flavonoids to smaller phenolic acids. However, there is very little information on bacterial transformations of anthocyanins.
Aim of the study
was to explore if anthocyanin glycosides were deglycosylated,whether the resulting aglycones were degraded further to smaller phenolic compounds by colonic bacteria, and to characterise metabolites.
Isolated cyanidin–3–glucoside and –rutinoside were fermented in vitro using human faecal microbiota as an inoculum. Metabolites were analysed and characterised by HPLC–DAS and LC–MS. They were identified by comparing their characteristics with those of available standards, and semi–quantified using the amount of substrate analysed from samples at initial timepoint.
Cyanidin–3–glucoside and cyanidin aglycone could be identified as intermediary metabolites of cyanidin–3–rutinoside. At early timepoints (before 2 h), the formation of protocatechuic acid as a major metabolite for both cyanidin glycosides and detection of lower molecular weight metabolites show that anthocyanins were converted by gut microflora. Furthermore, reconjugation of the aglycone with other groups, non–typical for dietary anthocyanins, was evident at the later (after 2h) timepoints.
Bacterial metabolism of anthocyanins involves the cleavage of glycosidic linkages and breakdown of the anthocyanidin heterocycle.
- In vitro metabolism of anthocyanins by human gut microflora
European Journal of Nutrition
Volume 44, Issue 3 , pp 133-142
- Cover Date
- Print ISSN
- Online ISSN
- Additional Links
- alpha, L-rhamnosidase
- beta, D-glycosidase
- bacterial metabolism
- heterocycle breakdown
- Industry Sectors
- Author Affiliations
- 1. VTT Biotechnology, 1500, 02044 VTT, Espoo, Finland
- 2. Universidad de Salamanca, Area de Nutrición y Bromatología – Facultad de Farmacia, Campus Miguel de Unamuno, Salamanca, Spain
- 3. Dept. of Health Toxicology Unit, Section on Clinical Pharmacology Imperial College, Hammersmith Campus, London, UK
- 4. Nutrient Bioavailability Group, Nestlé Research Center, Lausanne, Switzerland