Intestinal bacterial metabolism of flavonoids and its relation to some biological activities

Abstract

Flavonoid glycosides were metabolized to phenolic acids via aglycones by human intestinal microflora producing alpha-rhamnosidase, exo-beta-glucosidase, endo-beta-glucosidase and/or beta-glucuronidase. Rutin, hesperidin, naringin and poncirin were transformed to their aglycones by the bacteria producing alpha-rhamnosidase and beta-glucosidase or endo-beta-glucosidase, and baicalin, puerarin and daidzin were transformed to their aglycones by the bacteria producing beta-glucuronidase, C-glycosidase and beta-glycosidase, respectively. Anti-platelet activity and cytotoxicity of the metabolites of flavonoid glycosides by human intestinal bacteria were more effective than those of the parental compounds. 3,4-Dihydroxyphenylacetic acid and 4-hydroxyl-phenylacetic acid were more effective than rutin and quercetin on anti-platelet aggregation activity. 2,4,6-Trihydroxybenzaldehyde, quercetin and ponciretin were more effective than rutin and ponciretin on the cytotoxicity for tumor cell lines. We insist that these flavonoid glycosides should be natural prodrugs.

A randomised trial to investigate the effects of acute consumption of a blackcurrant juice drink on markers of vascular reactivity and bioavailability of anthocyanins in human subjects

“…The peak at 30 min indicated that metabolites of phenolic components in the juice, which were absorbed in the small intestine, contributed to the concentrations of these phenolic acids. Benzoic acid and hippuric acid are known to be colonic metabolites of anthocyanins (Kim et al, 1998). However, concentrations of the four phenolic acids decreased gradually after peaking at 30 min, indicating further chemical or microbial degradation of the phenolic compounds, as suggested by Keppler and Humpf (2005).…”

Biochemical Characteristics, Antimicrobial and Mutagenic Activity in Organically and Conventionally Produced Malus domestica, Annurca

“…Furthermore, the good percentage of p-coumaric acid found in the organically and conventionally produced Annurca could be significant since this biomolecule has received a lot of attention in the recent years for its anti inflammatory in vivo properties [23]. Moreover, the high level of chlorogenic acid, observed mainly in organic fruits is of great meaning as in vivo studies have demonstrated the antioxidant and anticarcinogenic properties of this biomolecule, in general inefficiently absorbed in small intestine, but capable of providing higher yields of microbial metabolites, active compounds responsible for the biological properties attributed to dietary polyphenols [24][25]. The characterization of conventional and organic apple aimed at the identification of compounds developed by plant tissues as part of their defence mechanism was carried out by Lucarini et al [26], which indicated higher levels of both polyphenols and specific phenolic acids, as p-coumaric and caffeic acid, in organically than in conventionally produced apples.…”

Treatment of Mice with Naringin Alleviates the Doxorubicin-Induced Oxidative Stress in the Liver of Swiss Albino Mice

“…23 It is also transformed by the intestinal microflora into many kinds of phenolic acids due to ring fission. 24,25 The hydrolysis of naringin results into naringenin in the intestine and is catalyzed by enzymes including α-rhamnosidases and β-glucosidases. 26,27 Naringin interacts with the activities of transporters and enzymatic proteins in the intestine and hence, with the absorption and breakdown of certain drugs, results in altered blood levels.…”