UNLABELLED Quercetin exerts vasodilator, antiplatelet and antiproliferative effects and reduces blood pressure, oxidative status and end-organ damage in hypertensive humans and animal models. We hypothesized that oral quercetin might induce vasodilator effects in humans and that they might be related to the deconjugation of quercetin-3-O-glucuronide (Q3GA). DESIGN double blind, randomized, pl...

We report here the cloning and optimized expression at 16 degrees C and the characterization of a Vitis vinifera UDP-glucose:flavonoid 3-O-glucosyltransferase, an enzyme responsible for a late step in grapevine anthocyanin biosynthesis. The properties of this and other UDP-glucose:flavonoid 3-O-glucosyltransferases, homologues of the product encoded by the maize Bronze-1 locus, are a matter of ...

The bioactive N-butanol fraction of the ethanol extract of the leaves of Cissus ibuensis was fractionated over silica Gel column to give Quercetin 3-O-rutinoside (I) and mixtures of Flavonoids (A2). A2 was fractionated using reverse phase HPLC to give Kaempferol 3-O-α-rhamnopyranosyl (1→6)-β-D-galactopyranoside (II), Kaempferol 3-O-rutinoside(III) and Kaempferol3-O-α-rhamnopyranosyl (1→6)-α-rha...

The phytochemical study of flowering shoots of Caragana bungei Ledeb., Fabaceae, collected in Tuva Republic (Russian Federation) resulted in the isolation of sixteen compounds identified as β-sitosterol, β-sitosterol-3-Oglucoside, umbelliferone, kaempferol, quercetin, isorhamnetin-3-O-glucoside, isoquercitrin, rutin, narcissin, nicotiflorin, caffeic acid, 3-O-caffeoylquinic acid, 5-O-caffeoylqu...

The chemical composition of plant polyphenols Plantago major L. and lanceolata growing in Uzbekistan was studied. More than 20 compounds, including 7 flavonoids, 9 phenolic acids, 8 hydrolysable tannins, the ages which have been determined using physicochemical methods research isolated from plants. From P. L., along with well-known such as gallic acid, rutin, luteolin, isorhamnetin, hyperoside...

Four O-acylated flavonol glycosides, new in the plant kingdom, were isolated from the needles of Pseudotsuga menziesii. Their structures were established by 1D and 2D NMR and MS data as: daglesioside I [kaempferol 3-O-[2",5"-O-(4''',4(IV)-dihydroxy)-beta-truxinoyl]-alpha-L-arabinofuranoside] (1), daglesioside II [kaempferol 3-O-[2",5"-O-(4"'-hydroxy)-beta-truxinoyl]-alpha-L-arabinofuranoside] (...

Tilia species, among which is Tilia cordata Mill. (Tiliaceae), have been used in folk medicine as anxiolytic. The hydroethanolic extract was analyzed by using liquid chromatography with mass spectrometry HPLC-DAD-ESI-MS/MS in negative ion mode, and its chemical composition was compared to flavonoids reported as anxiolytics. The major flavonoids found were: quercetin-3,7-di-O-rhamnoside, kaempfe...

Quercetin derivatives are known to have significant anticancer activity. The activity is strongly influenced by the type and position of substituent group. By studying structural pattern quercetin its impact on their binding affinity, development quercetin-based drugs can be optimized. study aimed determine 3D structure, type, moiety against ROS-modulating enzymes that play a role in induction ...

This study aims to identify special metabolites in polar extracts from Urochloa humidicola (synonym Brachiaria humidicola) that have allelopathic effects and induce secondary photosensitization in ruminants. The compounds were isolated and identified via chromatographic and spectroscopic techniques. The compounds 4-hydroxy-3-methoxy-benzoic acid, trans-4-hydroxycinnamic acid, and p-hydroxy-benz...