Whilst mitotic rat embryonic cardiomyoblast-derived H9c2 cells have been widely used as a model system to study the protective mechanisms associated with flavonoids, they are not fully differentiated cardiac cells. Hence, the aim of this study was to investigate the cardioprotective and cardiotoxic actions of quercetin and two of its major in vivo metabolites, quercetin 3-glucuronide and 3'-O-m...

Carob leaves (Ceratonia siliqua L.), grown in Egypt have not fully identified in Egypt. Therefore, eight major phenolic compounds were isolated from the aqueous ethanolic extract using different methods of chromatography; gallic acid, quercetin 3-O-4C1-B-D-glucoside (Isoquercetin), Kaempferol 3-O1C4-"-Lrhamnoside (Afzelin), Quercetin 3-O-1C4-"-L-rhamnoside (Quercitrin), 1,2,6 tri-O-galloyl-B-D4...

Quercetin is a flavonoid usually found in fruits and vegetables. Aside from its antioxidative effects, quercetin, like other flavonoids, has a various neuropharmacological actions. Quercetin-3-O-rhamnoside (Rham1), quercetin-3-O-rutinoside (Rutin), and quercetin- 3-(2(G)-rhamnosylrutinoside (Rham2) are mono-, di-, and tri-glycosylated forms of quercetin, respectively. In a previous study, we sh...

The antimicrobial activity against fish bacterial pathogens of flavonoids (morin, morin-3-O-lyxoside, morin-3-O-arabinoside, quercetin, and quercetin-3-O-arabinoside) isolated from the leaves of Psidium guajava was evaluated. The flavonoids were shown to have bacteriostatic effect on all of the tested bacteria.

Phytochemical investigation of the leaves of Sutherlandia frutescens led to the isolation of four new 3-hydroxy-3-methylglutaroyl-containing flavonol glycosides, sutherlandins A-D ( 1- 4). Their structures were elucidated by chemical and spectroscopic methods as quercetin 3- O- beta- D-xylopyranosyl(1 --> 2)-[6- O-(3-hydroxy-3-methylglutaroyl)]- beta- D-glucopyranoside ( 1), quercetin 3- O- bet...

8-beta-Hydroxypimar-15-en-19-oic acid (1), taxodione (2), 6,7-dehydro-8-hydrotaxodone (3), quercetin-3-O-beta-D-glucopyranoside (4), and shikimic acid (5) were isolated from the leaves of Taxodium distichum L. (Rich.) for the first time. Previously reported compounds [beta-sitosterol (6), isorhamnetin (7), quercetin (8), isorhamnetin-3-O-alpha-arabinofuranoside (9), quercetin-3-O-a-arabinofuran...

A high-throughput method for the extraction and analysis of quercetin in human plasma using 96-well SPE and LC-(ESI)MS/MS (7 min/run) is described. Quercetin exists as a range of glycosides in foods. The dominant types of quercetin glycosides vary depending on genetics (i.e., species and cultivar). Dietary sources include onions and apples (i.e., the peel). Herein the quercetin glycoside compos...

The antioxidant activity of the aqueous ethanolic extract of Doum leaves, Hyphaene thebaica L. (Palmae), was studied. Data obtained showed that the extract scavenged superoxide anion radicals (IC50=1602 μg/ml) in a dose dependant manner using xanthine/hypoxanthine oxidase assay. Four major flvonoidal compounds were identified by LC/SEI as; Quercetin glucoside, Kaempferol rhamnoglucoside, Dimeth...

Detailed chemical investigation of the herb Sarcopyramis bodinieri var. delicate resulted in the isolation of two new flavonol glycosides, namely, isorhamnetin-3-O-(6''-OE-feruloyl)-beta-D-glucopyranoside (1) and isorhamnetin-3-O-(6''-O-E-feruloyl)-beta-Dgalactopyranoside (2). In addition, four known compounds, quercetin-3-O-(6''-acetyl)-beta-Dglucopyranoside (3), isorhamnetin-3-O-(6''-acetyl)-...