Albizia species have been shown to have anti-inflammatory and anti-allergic properties. However, efficient analytical methods for identification of their active constituents are still lacking. Ultra-performance liquid chromatography coupled with electrospray ionization-quadrupole time-of-flight mass spectrometry (UPLC-ESI-QTOF-MS) was used to study the phenolic composition of the ethanolic extr...

east of China. It has long been used as a traditional crude drug for the treatment of bronchial asthma and chronic bronchitis. Previous investigations of the whole plants of E. lanulata have yielded kaempferol, quercetin, kaempferol 3-O-Lrhamnoside, quercetin 3-O-L-rhamnoside, 6,7-dihydroxycoumarin and maoyancaosu. More than 30 types of cytokines and growth factors have been identified as ligan...

Plants are rich in secondary metabolites, which often useful as a relevant source of nutraceuticals. Quercetin (QUE) is flavonol aglycone able to bind Transthyretin (TTR), plasma protein that under pathological conditions can lose its native structure leading fibrils formation and amyloid diseases onset. Here, the dual nature five quercetin 3-O-glycosylated derivatives, isolated from different ...

Etoposide [4'-demethylepipodophyllotoxin-9-(4,6-O-ethylidene)-beta-D-glucopyranoside] is a substrate for P-glycoprotein (P-gp) and cytochrome P450 (CYP) 3A. This study was designed to investigate the effects of quercetin (3,5,7,3',4'-pentahydroxyflavanone), a P-gp and CYP3A inhibitor, on the pharmacokinetics of etoposide in rats. Etoposide was administered to rats orally (9 mg/kg) or i.v. (3 mg...

Three phenolic compounds, p-hydroxybenzoic acid (1), isorhamnetin-3-O-β-D-rutinoside (2), and 3,3'-di-O-methylquercetin (5), along with a phenolic mixture were successfully separated from the ethyl acetate crude extract of Halimodendron halodendron by high-speed counter-current chromatography (HSCCC) with chloroform-methanol-water-acetic acid (4:3:2:0.05, v/v) as the two-phase solvent system. T...

Amygdalus persica L., belongs to Rosaceae family, and its flowers are used as medicine food. n-Butanol extract of A. were isolated purified with various column chromatographies, the fourteen compounds, chlorogenic acid butyl ester (1), rutin (2), protocatechuic (3), caffeic (4), 5-O-coumarroylquinic methyl (5), kaempferol-3-O-neohesperidoside (6), quercetin-3-O-β-D-glucoside (7), 3,5-dicaffeoyl...

As part of our ongoing research on antioxidant agents from Brazilian flora, we screened the free radical scavenging activity of two extracts and eight fractions of Kielmeyera variabilis (Clusiaceae) using DPPH· (2,2-diphenyl-1-picrylhydrazyl-hydrate) and ABTS·+ [2,2'-azinobis(3-ethylenebenzothiazoline-6-sulfonic acid)] colorimetric assays. The ethyl acetate and n-butanol fractions of the leaves...

Abstract The antioxidant, photoprotective and antinociceptive Marcetia macrophylla active extract was investigated as an ingredient in a sunscreen cream formulation. Thus, the M. showed IC50 of 3.43 mg/ml antioxidant (DPPH∙ scavenging test) Sun Protection Factor 20.25 (SPF/UV-B, at 250 µg/ml) UV-A 78.09% (photobleaching trans-resveratrol test). activity superior to all standards tested using vi...

Chromatographic separation of a 70% aqueous methanol extract (AME) of Pongamia pinnata (Linn.) Pierre (Leguminosae) leaves has led to the isolation of two new isoflavonoid diglycosides, 4'-O-methyl-genistein 7-O-beta-D-rutinoside (2) and 2',5'-dimethoxy-genistein 7-O-beta-D-apiofuranosyl-(1"'-->6")-O-beta-D-glucopyranoside (6), and a new rotenoid, 12a-hydroxy-alpha-toxicarol (5), together with ...

Quercetin is a major dietary flavonoid found in onions and other vegetables. It is known that dietary quercetin is metabolized in the intestinal mucosa and the liver and is present as its glucuronide/sulfate conjugates with or without methylation. Although quercetin is known to possess strong antioxidant activity, there are only limited reports on the antioxidant activity of its metabolites. In...