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Bogs, J., Ebadi, A., Mcdavid, D. & Robinson, S.P. (2006): Identification of the flavonoid hydroxylases from grapevine and their regulation during fruit development. Pl. Physiol. , 140 , 279–291. Robinson S

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Girzu, M. A., Carnat, A., Fraisse, D., Carnat, A. P. and Lamaison, J. L. (2000): Flavonoid and dianthranoid levels of the St. John’s wort flowering tops. — Annal. Pharm. Francaises 58 : 341–345. Lamaison J

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date, bamboo leaf extract has been reported to exhibit antioxidant, antibacterial, antitumor, anti-inflammatory, antimicrobial, and antiulcerogenic activities [ 2 – 6 ]. Phytochemical research on PES leaves has revealed the functions of 4 flavonoids and

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Dixon, R. A., Xie, D.-Y., Sharma, S. B. (2005) Proanthocyanidins — a final frontier in flavonoid research? New Phytol. 165 , 9–28. Sharma S. B. Proanthocyanidins — a final frontier in

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. investigated that essential oil and total flavonoids of O. falcata showed antiproliferative activity on SMMC-7721 through down-regulating secretion and expression of MMP-2 in cells [ 6 ]. Yang et al. reported that total flavonoid of O. falcata is a pro

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Summary

Scutellaria L. is a diverse genus of the Lamiaceae (Labiatae) family of over 300 herbaceous plants commonly known as skullcaps. Various species of Scutellaria are used as ethnobotanical herbs for the treatment of ailments like cancer, jaundice, cirrhosis, anxiety, and nervous disorders. Scutellaria incana L., commonly known as the Hoary skullcap, is a traditional medicinal plant used by native Americans as a sedative for nervousness or anxiety. S. incana metabolites were identified by comparing their high-performance liquid chromatography (HPLC) retention times and mass spectra with those of the corresponding authentic standards. Where standards were unavailable, the structures were characterized on the basis of their tandem mass spectrometry (MS/MS) spectra following collision-induced dissociation (CID) and the accurate masses of the corresponding deprotonated molecules [M-H] (mass accuracy ± 5 ppm). A total of 40 flavonoids, including two phenolic glycosides, were identified from leaves, stems, and roots of S. incana. Differences in the flavonoid composition between leaves, stems, and roots in S. incana were observed although the flavonoid profile of S. incana is consistent with other Scutellaria species. Further work should focus on assessing the potential of S. incana as a source of these bioactive metabolites.

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A high-performance liquid chromatographic (HPLC) technique coupled with photodiode array (PDA) detection has been proposed for simultaneous determination of five flavonoids, i.e. quercetin 3-O-β-d-glucopyranoside, quercetin 4′-methoxy-3-O-β-d-galactopyranoside, kaempferol 3-O-β-l-rhamnopyranoside, asebotin, and kaempferol 7-methxoy-3-O-α-l-rhamnopyranoside in extract of the whole plant of Saussurea mongolica Franch. The optimum conditions for separation were achieved on a 4.6 × 250 mm i.d., 5-μm particle, C18 column with acetonitrile and 1% acetic acid (20:80, v/v) as the mobile phase at a flow rate of 1.0 mL min−1. For all the analytes, a good linear regression relationship (r of >0.999) was obtained between peak area and concentration over a relatively wide range. The method was validated for repeatability, precision, stability, and accuracy. Seven different extraction procedures were investigated for preparation of the sample solution. The validated method was successfully applied to simultaneous analysis of these flavonoids in S. mongolica and was found to be simple and efficient.

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Red amaranth (Amaranthus cruentus) and quinoa (Chenopodium quinoa) are pseudocereals with particularly highly regarded nutritional value. Because of the high biological significance of the flavonoids and phenolic acids in these plants, qualitative and quantitative analysis has been performed by HPLC. Extracts from the seeds of two amaranth varieties (A. cruentus v. Rawa and v. Aztek) and quinoa seeds, and their sprouts grown in natural conditions and in the dark were analyzed. The main phenolic acid found both in seeds and sprouts was gallic acid. p-Hydroxybenzoic acid, vanillic acid, p-coumaric acid, caffeic acid, and cinnamic acid were also found in the seeds and p-coumaric acid, syringic acid, and ferulic acid in the sprouts. The main flavonoid found in the sprouts was rutin. Vitexin, isovitexin, and morin were also detected in the sprouts, and orientin, vitexin, isovitexin, morin, and traces of hesperidin and neohesperidin in the seeds. Although sprouting conditions (daylight or darkness) had no effect on gallic acid content, light caused an increase in the amount of rutin and darkness resulted in increased amounts of isovitexin and vitexin.

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Epimedium pubescens Maxim. and Epimedium koreanum Nakai. are two common and confused species of Herba Epimedii in Chinese Pharmacopoeia 2010 edition. Different species and growing conditions lead to chemical differences between the two species which may result in the improper clinical usage. In this work, a new method based on rapid-resolution liquid chromatography combined with time-of-flight mass spectrometry (RRLC/TOFMS) has been developed for identification and differentiation of major flavonoids in two kinds of Epimedium extract and rat plasma. The compounds were identified effectively based on the accurate extract masses and formulae acquired by RRLC/TOFMS. The fragmentation rules deduced by collision-induced dissociation (CID) were successfully implemented in distinguishing some of the isomers, further validating the results. By using the combined analytical techniques, a total of 40 major flavonoids in extracts of two kinds of Epimedium were identified within 30 min, including 31 common components and 9 characteristic components. After oral administration, three prototype compounds in rat plasma were detected by comparing the constituents measured in vitro with those in vivo, and five metabolites were identified by contrasting the fragmentation rules. The identification and structural elucidation of the chemical constituents provided essential data for further pharmacological and clinical studies on different species of Epimedium.

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A new, sensitive, and selective high-performance liquid chromatography-tandem mass spectrometric method (HPLC-MS/MS) has been developed for the quantification of six flavonoids (sophoricoside, genistin, genistein, rutin, quercetin, and kaempferol) in rat bile and urine. The sample pretreatment was simple by liquid-liquid extraction. Sulfamethalazole was used as internal standard (IS). During method development, the effect of extraction volume, mobile phase composition, column temperature, and injection volume were varied to optimize sensitivity and achieve a run time as short as possible. Chromatographic separation was accomplished on a C18 column with a simple linear gradient elution within 9 min. Full validation of the assay was in accordance with the requirement of the validation of the method in vivo and implemented including specificity, linearity, accuracy, precision, recovery, and matrix effect. This is the first report on determination of the major flavones in rat bile and urine after oral administration of Fructus Sophorae extract. The method has been used successfully in excretion studies of six major flavonoids in rat bile and urine.

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