From the needles of Taxus baccata the following flavonoids were isolated: 3-O-rutinosides quercetin, myricetin and kaempferol, 7-O-glucosides kaempferol and quercetin, kaempferol, quercetin, myricetin. The composition of flavonols and biflavones in some of the species of the genus Taxus, namely T. celebica, T. cuspidata, T. media and cultivar varieties T. baccata 'Aurea', T. baccata 'Aurea deco...

Phytochemical investigations of ethyl acetate-soluble part of the aerial part of Hypericum scabrum L. delivered eight pure phenolic compounds 1-8. The pure compounds were identified through physico-chemical, NMR (1D, 2D) and mass spectrometric studies as: 3-8''-bisapigenin (1), quercetin (2), quercetin-3-O-α-l-arabinofuranoside (3), quercetin-3-O-α-l-rhamnoside (4), quercetin-3-O-β-d-glucopyran...

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 flavonol quercetin, is one of the major flavonoids found in edible plants. The bioavailability of quercetin in humans may be influenced by the food matrix in which it is consumed as well as by its chemical and physical form. The objective of the present study was to investigate the biokinetics of quercetin from quercetin-enriched cereal bars and quercetin powder-filled hard capsules. In a r...

Two new triterpenoid saponins have been isolated from leaves and flowers of Crotalaria madurensis Wight&Arn named; sophradiol 3-O-β-D-C1-glucopyranosyl-(1''→4')-O-β-DC1 glucuronopyranoside (3) and sophradiol 3-Oα-LC4rhamnopyranosyl (1'''→4'')-O-ß-D-C1 glucopranosyl-(1''→6')-O-ß-DC1-glucopyranoside (4) beside myo-inositol (1) and three other triterpene saponin their structures were established a...

Plants produce two flavonoid O-pentoses, flavonoid O-xyloside and flavonoid O-arabinoside. However, analyzing their biological properties is difficult because flavonoids are not naturally produced in sufficient quantities. In this study, Escherichia coli was used to synthesize the plant-specific flavonoid O-pentosides quercetin 3-O-xyloside and quercetin 3-O-arabinoside. Two strategies were use...

Department of Chemistry and Research Institute of Basic Science, Chonnam National University, Gwangju 500-757, Korea Department of Chemistry, and Research Institute of Life Science, Gyeongsang National University, Chinju 660-701, Korea Department of Chemical Education, and Research Institute of Life Science, Gyeongsang National University, Chinju 660-701, Korea. *E-mail: [email protected] Receiv...

Five minor flavonoid monosides, glycosides of quercetin and kaempferol, together with three previously isolated compounds were identified cochromatographically in P. serotina Ehrh. leaves and flowers (inflorescences) using RP-HPLC and TLC techniques and finally determined as quercetin 3-O-alpha-L-arabinofuranoside (avicularin), 3-O-alpha-L-arabinopyranoside (guaijaverin), 3-O-beta-D-xylopyranos...

Flaveria bidentis (L.) Kuntze is an annual alien weed of Flaveria Juss. (Asteraceae) in China. Bioactive compounds, mainly flavonol glycosides and flavones from F. bidentis (L.) Kuntze, have been studied in order to utilize this invasive weed, Analytical high-performance counter-current chromatography (HPCCC) was successfully used to separate patuletin-3-O-glucoside, a mixture of hyperoside (qu...