Cydonia oblonga Miller leaves phenolic compounds were analyzed by reversed-phase HPLC/DAD and HPLC/UV. Qualitative and quantitative analysis of phenolics were carried out in a total of 36 samples of quince leaves from three different geographical origins of Northern (Bragança and Carrazeda de Ansiães) and Central Portugal (Covilhã) and three collection months (June, August, and October of 2006)...

The characterization and quantification of phenolic compounds in bearberry leaves were performed using hyphenated ion mobility spectroscopy (IMS) a quadrupole time-of-flight mass spectrometer. A higher identification confidence level was obtained by comparing the measured collision cross section (TWCCSN2) with predicted values machine learning algorithm. total 88 identified, including 14 arbuti...

A number of natural and synthetic flavonoids have been assessed previously with regard to their effects on the activity of cyclin-dependent kinases (Cdk1 and -2) related to the inhibition of cell cycle progression. On the other hand, the Cdk5/p35 system is of major importance in neuronal migration phenomena and brain development, and its deregulation is implicated in neurodegenerative diseases,...

in the present study, we investigated the variation in the content of naphthodianthrones hypericin and pseudohypericin, phloroglucinol derivatives hyperforin and adhyperforin, the phenolic acids as chlorogenic acid, neochlorogenic acid, 2,4-dihydroxybenzoic acid, and the flavonols, namely, hyperoside, isoquercitrin, quercitrin, quercetin, avicularin, rutin, (+)-catechin and (-)-epicatechin, and...

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 ...

Wild-type Arabidopsis L. leaves exposed to low ultraviolet-B (UVB) conditions contained predominantly kaempferol glycosides, with low levels of quercetin glycosides. The flavonoid level doubled on treatment with UVB and an increase in the ratio of quercetin: kaempferol was observed. These results suggest that flavonols protect Arabidopsis plants from UVB damage, and indicate that the flavonoid ...

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...