Efficiency of absorption and metabolic conversion of quercetin and its glucosides in human intestinal cell line Caco-2.
Archives of biochemistry and biophysics
confidence
Key findings
Quercetin aglycone absorbed/conjugated more efficiently than glucosides; Q4'G better absorbed than Q3G/Q3,4'G due to higher lipophilicity.
View source on PubMed (PMID 11368329) ↗
- Sample size
- Not applicable (cell culture)
- Population
- In vitro Caco-2 human intestinal cell line
- Dosing
- Not reported
- Duration
- Not reported
- Route
- Apical (intestinal epithelial model)
- Blinding
- not_reported
- Controls
- none
- Drug class
- flavonoid
Full abstract
The efficiency of intestinal absorption and metabolic conversion of quercetin aglycone and its glucosides, quercetin-4'-O-beta-D-glucoside (Q4'G), quercetin-3-O-beta-D-glucoside (Q3G), and quercetin-3,4'-di-O-beta-D-glucoside (Q3,4'G), was estimated by using Caco-2 cell monolayers as an intestinal epithelial cell model. Aglycone was significantly lost from the apical side, resulting in the appearance of free and conjugated forms of quercetin and those of isorhamnetin in the cellular extracts. In the basolateral solution, the conjugated form of quercetin was predominant and increased with the elapse of incubation. As compared with quercetin aglycone, none of the quercetin glucosides were absorbed efficiently from apical side. However, Q4'G yielded conjugated quercetin and isorhamnetin in basolateral solution at higher amounts than Q3G or Q3,4'G. Lipophilicity of Q4'G was found to be higher than that of Q3G or Q3,4'G. This suggests that lipophilicity contributes to the relatively efficient absorption of Q4'G. It is likely that the occurrence of hydrolysis enhances the efficiency of intestinal absorption and metabolic conversion of dietary quercetin glucosides.