five flavonoid glycosides were isolated from the n-butanol soluble fraction of the ethanolic extract of rapistrum rugosum and their structures were assigned from 1h- and 13c-nmr spectra (dept) with 2d nmr as quercetin-3-o-α-l-rhamnopyranoside (1), quercetin-3-o-β-d-xyloside (2), quercetin, 3-o-α-l-arabinopyranoside,7-o-α-l-rhamnopyranoside (3), kaempferol 3-o-α-l-arabinopyranoside, 7-o-α-l-rham...

...........................................................................................................................................v LIST OF TABLES..................................................................................................................................x LIST OF FIGURES..................................................................................................

OBJECTIVES The present study analysed, for the first time, the effects of the flavonoid quercetin in rats after chronic inhibition of nitric oxide (NO) synthesis with Nomega-nitro-L-arginine methyl ester (L-NAME). DESIGN Rats were divided randomly into five different treatment groups for 6 weeks: (1) vehicle (control, 1 ml of 1% methylcellulose once daily); (2) vehicle plus L-NAME (75 mg/100 ...

The anti-ulcerogenic and anti-oxidant effects of various flavonoids have been frequently reported. We investigated the cytoprotective properties of quercetin, a natural flavone, in gastric mucosal injury induced by 50% ethanol, since in this experimental model the pathogenesis of the lesions has been related with production of reactive oxygen species. The involvement of neutrophil infiltration ...

Flavonoids have been reported to be potent antioxidants and beneficial in the treatment of oxidative stress-related diseases. Quercetin, a major flavonoid naturally occurring in plants, deserves attention because of its beneficial effects observed in various in vitro and in vivo neural damage models; however, the actions of quercetin are paradoxical. In an effort to confirm the neuroprotective ...

The flavonoid quercetin has been reported to inhibit the proliferation of cancer cells, whereas it has no effect on nonneoplastic cells. U87-MG, U251, A172, LN229, and U373 malignant glioma cells were treated with quercetin (50-200 microM). Quercetin did not cause cytotoxicity 24 h after treatment. Combining quercetin with tumor necrosis factor-related apoptosis-inducing ligand (TRAIL) strongly...

Quercetin, a plant-derived flavonoid found in fruits, vegetables and tea, has been known to possess bioactive properties such as anti-oxidant, anti-inflammatory and anti-cancer. In this study, anti-cancer effect of quercetin and its underlying mechanisms in triple-negative breast cancer cells was investigated. MTT assay showed that quercetin reduced breast cancer cell viability in a time and do...

The effect of quercetin, a flavonoid found in many plants, on the proliferation of human leukemic T-cells was analyzed. Quercetin reversibly blocked the cell cycle at a point 3-6 h before the start of DNA synthesis. Expression of the growth-related genes histone H4, cyclin A and B, and p34 ~dc2 was suppressed in cells blocked with quercetin. Comparison of the quercetin arrest points with those ...

Quercetin is a plant-derived flavonoid that is widely distributed in nature. The present study is designed to analyze the underlying mechanism in the protection of quercetin against pyrrolizidine alkaloid clivorine-induced acute liver injury in vivo. Serum transaminases, total bilirubin analysis, and liver histological evaluation demonstrated the protection of quercetin against clivorine-induce...