The edible flowers of Caragana sinica are used in China a kind of healthpromoting vegetable. In this study, the antioxidant activities of its ethanol extract, as well as its petroleum ether, ethyl acetate, n-butanol and water fractions, were evaluated through in vitro model systems including the DPPH, FRAP and β-carotene bleaching methods. Among the C. sinica flower extracts the ethyl acetate f...

The squamous cell carcinomas of the head and neck (SCCHNs) with aberrant epidermal growth factor receptor (EGFR) signaling are often associated with poor prognosis and low survival. Therefore, efficient inhibition of the EGFR signaling could intervene with the development of malignancy. Quercetin appears to be antitumorigenesis, but the underlying mechanism remains unclear in oral cancer. Fork-...

Inflammatory bowel disease (IBD) including Crohn's disease (CD) and ulcerative colitis (UC) is a chronic inflammatory gastrointestinal autoimmune condition with an inappropriate immune response. We investigated DNA damage induced in vitro in lymphocytes from IBD patients caused by oxidative stress through H(2)O(2) and 2-amino-3-methylimidazo[4,5-f]quinoline (IQ) and whether the plant flavonoids...

Flavonol 3-O-diglucosides with a 1→2 inter-glycosidic linkage are representative pollen-specific flavonols that are widely distributed in plants, but their biosynthetic genes and physiological roles are not well understood. Flavonoid analysis of four Arabidopsis floral organs (pistils, stamens, petals and calyxes) and flowers of wild-type and male sterility 1 (ms1) mutants, which are defective ...

In searching for tyrosinase inhibitors from plants using L-3,4-dihydroxyphenylalanine (L-DOPA) as a substrate, quercetin was found to be partially oxidized to the corresponding o-quinone under catalysis by mushroom tyrosinase (EC 1.14.18.1). Simultaneously, L-DOPA was also oxidized to dopaquinone and both o-quinones were further oxidized, respectively. The remaining quercetin partially formed a...

From the leaves of Cucumis sativus the following C-glycosides were isolated and identified: isovitexin 2"-O-glucoside, isovitexin, isoorientin, 4'-X-O-diglucosides of isovitexin and swertiajaponin. In the flowers of the above species chromatographically (HPLC, TLC) the presence of kaempferol 3-O-rhamnoside and 3-O-glycosides of kaempferol, quercetin, isoramnetin was revealed. The flavonoids com...

In pollen, flavonoids are usually found as glycosides and in particular, flavonol 3-O-diglycosides. However, in members of the Myrtaceae, subfamily Leptospermoideae, the rare flavone aglycone tricetin, along with other flavonoid aglycones including 3-O-methyl quercetin and luteolin, have been found to comprise a significant portion of the constituent flavonoids.

Introduction. Natural sources, especially plants, have been used in folk medicine of various countries for many centuries and appears as rich sources natural compounds. One the interesting plants study is yellow loosestrife ( Lysimachia vulgaris L.), information on chemical composition which scarce. Aim. Carry out a phytochemical research L. aerial part, by isolation individual secondary metabo...

Quercetin and galangin can change the activity of glutathione reductase. Quercetin (a catechol structure in the B-ring) and galangin (any hydroxyl group in the B-ring) have different biological activities but, both possess high antioxidant abilities. Quercetin during the antioxidative action, is converted into an oxidized products (o-semiquinone and o-quinone), and subsequently glutathionyl add...