Procyanidin glycoside

Hypertension is an important risk factor for coronary heart disease and stroke. Since ancient times, hypertensive patients have been treated orally with plant extracts based on folk medicine. However, and despite their in vitro vasodilator effects, little information about the protective effects of flavonoids on hypertension is available in the literature. Flavonoids have been considered as active principles of several antihypertensive plant extracts (e.g. rhamnoglycoside of limocitrin isolated from Citrus limonum, kaempferol 4 -0-glucose and hyperin from Euphorbia maddeni, moracenins from Morus alba, procyanidin glycoside from Rhamnus lycioides) [150,151]. In all cases, only the acute antihypertensive effects after i.v. administration in anaesthetised normotensive and/or hypertensive animals have been described. In addition to the direct vasodilator effects discussed above, the inhibition of angiotensin-converting enzyme reported... 

Bae YS, Burger JFW, Steynberg JP, Ferreira D, Hemingway RW (1994) Havan and procyanidin glycosides from the bark of blackjack oak. Phytochemistry 35 473-478... 

The effects of catechin, epicatechin, procyanidin B2, caffeic acid, / -coumaric acid, myricetrin, and quercetrin on the color intensity and stability of malvidin 3-glucoside at a molar ratio of 1 1 under conditions similar to red wine were evaluated. " Flavan 3-ols appeared to have the lowest protective effects and flavonols the highest strong color changes were visually perceptible. " In the complexation of malvin chloride and natural polyphenols, flavonol glycosides by far exerted the best protector effect. ... 

The NOESY experiment has also been very useful for revealing the presence of rotational conformers of dimeric flavonoids and flavone C-glycosides (Figure 2.3). Strong exchange crosspeaks between equivalent protons of each conformer revealed the rotational equilibriums. This NOE phenomenon was first noted by Hatano et al. in two conformers of procyanidin dimers. The volume of the NOESY crosspeaks is related to the distance... 

In general, the biological evaluation of hypericin in various test models is limited by its poor water solubility. It was shown in in vitro as well as in vivo studies (18,78) that the water solubility of hypericin was remarkably enhanced in the presence of procyanidins or flavonol glycosides of SJW extract. In a recent pharmacokinetic study in rats, it was shown that procyanidin B2 as well as hyperoside increased the oral bioavailability of hypericin by approximately 58% (B2) and 34% (hyperoside) (Fig. 5) (19). Procyanidin B2 and hyperoside had a different influence on the plasma kinetics of hypericin median maximal plasma levels of hypericin were detected after 360 minutes (Cmav 8.6 ng/mL) for B2, and after 150 minutes... 

N.A. Crataegus laevigata C. monongyna Jacq. C. oxyacantha L. Flavonoid glycosides, procyanidins, catechins, triterpenoid acid, pectins, amygdalin, proanthocyanidins, emulsin, tartaric acid, tannins, crataegus acid, rutin, coumarins, quercitin, amines 99,100,231,278,279 Therapeutic treatment of heart insufficiency, hypotensive, coronary blood supply, arrhythmia. 

Table 2 Gradient HPLC Procedure for Phenolic Acids, Flavonol Glycosides, and Procyanidins in Fruit Juices...

Fractionate phenolic acids and flavonoids using Sephadex LH-20 column. For phenolic acids and flavonol glycosides, filter the fruit juice through 0.45-/nm (type HA) filter. For procyanidins apply juice onto the Sephadex LH-20 column, wash with 20% MeOH (30 ml), then elute with MeOH (15 ml), concentrate to dryness, redissolve in 2 ml H20, and filter through 0.45-/nm (type HA) filter. 

Unlike some classes of polyphenols such as flavonols and flavones, flavanols are almost always present in the nonglycosylated form. Removal of glycoside from flavonoids, usually necessary before the transport across the intestinal barrier, is not required in the case of flavanols [Scalbert and Williamson, 2000]. The absorption of procyanidins by the small intestine was investigated by studying 14C-( + )-catechin, dimer, trimer, and procyanidin polymers permeation through Caco-2 cell cultures [Deprez et al., 2001]. There was little difference in permeability between monomer, dimmer, and trimer, based on the measurement of radioactivity present on the basal side of the cultures, whereas the permeability of the polymers was 10 times lower. The authors reported the absence of catechin metabolism but did not determine whether the radioactivity measured on the basal side of the cultures was from the parent dimers to polymers or from their products of degradation or metabolites, which could have resulted from instability of the parent compounds in the culture... 

Hong, Y-J. Tomas-Barberan, F.A. Kader, A.A. Mitchell, A.E. 2006. The flavonoid glycosides and procyanidin composition of Deglet Noor dates Phoenix dactyli-fera). J. Agric. Food Chem. 54 2405-2411. 

Procyanidins with different degrees of polymerization such as dimers, trimers, and polymers from extracts of different natural sources were found to be nonmutagenic in the Salmonella mutagenesis assay. Moreover, the mutagenic impurity in procyanidin B-4 was isolated by reversed-phase high-performance liquid chromatography (HPLC). Procyanidin B-4 was identified as rutin (flavonol O-glycoside, 3) (Fig. 22) [55]. 

Content and Recovery of Anthocyanins, Chlorogenic Acid, Flavonol Glycosides and Procyanidins in Highbush Blueberries (Vaccinium corymbosum var. Bluecrop) during Juice Processing1... 

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