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. G., Genova, E. and Porter, E. A. (2006): Exudate flavonoids from Bulgarian species from Salvia. - Biochem. Syst. Ecol. (in press). Exudate flavonoids from Bulgarian species from Salvia Biochem

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Although conventional solid phase extraction (SPE) is an applicable routine method for extraction of different analytes from various matrices, it requires more time and volume of solvent and sample rather than other routine laboratory extraction methods. In this study, a rapid and simplified sample preparation method based on SPE was studied by eliminating some steps, such as conditioning and washing, for extraction of diosmin, eriocitrin, narirutin, naringin, and hesperidin in orange, tangerine, and lime juice samples. The separation of these flavonoids was achieved by using a C8 column with a mobile phase comprised of water-acetonitrile-acetic acid (78:21:1, v/v/v) at a flow rate of 0.85 mL min−1 and UV detection at 280 nm. To examine the applicability of this method, effective parameters such as type of adsorbent, type and volume of elution solvent, ionic strength, and pH of the sample were studied and applied to the comparison between the conventional SPE and the simplified method. The best recoveries were obtained, using the proposed method, with a small volume of citrus fruit juice (0.5 mL), silica gel (0.5 g) as adsorbent, and 3 mL of methanol as elution solvent. Limits of detection, limits of quantification, intra-day and inter-day precision of the method for the analytes were 0.0244–0.0587 μg mL−1, 0.0739–0.178 μg mL−1, 2.5–3.1%, and 3.1–4.8%, respectively.

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The method of high-performance liquid chromatography (HPLC) with diode array detector (DAD) was used and validated for the simultaneous determination of nine flavonoids (rutin, myricetin, quercitrin, quercetin, luteolin, genistein, kaempferol, apigenin, and isorhamnetin) in beagle dog plasma. Plasma sample was pre-treated with acetonitrile (containing 0.05% formic acid). Chromatographic separation was performed on a kromasil C18 column (250 × 4.6 mm, 5 µm) maintained at 35 °C. The mobile phase was a mixture of methanol and 0.2% formic acid with a step linear gradient. At 1.0 mL min−1 flow rate, the eluent of other eight flavonoids was detected simultaneously at 360 nm with good separation except genistein (detected at 254 nm). Under optimum conditions, the correlation coefficient between the peak area and the concentrations for each analyte was all above 0.999. The intra-day and inter-day precisions were less than 10% for all analytes. The limit of detection and the limit of quantification for the selected nine flavonoids were 0.006–0.03 and 0.02–0.12 g mL−1, respectively. The extracted recoveries of selected nine flavonoids were 74.02%–99.37%. The assay has been successfully applied to determine concentrations of nine flavonoids in plasma from beagle dog after being intravenously administrated Ginkgo biloba extract.

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Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light-scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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Summary

Yanghuo Sanqi tablet (YST), combined prescription mainly derived from the leaves of Herba epimedii and the roots of Panax notoginseng, is a traditional Chinese medicine (TCM). Flavonoids (icarrin, epimedin A, epimedin B, epimedin C, and baohuoside I) and saponins (notoginsenoside R1, ginsenoside Rgl, and ginsenoside Rbl) are considered as the main bioactive compounds of YST. However, there is no report on quality control of TCMs by simultaneous determination of above-mentioned flavonoids and saponins so far. In this work, for the first time, a high-performance liquid chromatography-diode array detector-evaporative light scattering detector (HPLC-DAD-ELSD) method was developed to evaluate the quality of YST through a simultaneous determination of five major active flavonoids and three main saponins. Optimum separations were obtained with a Zorbax SB-C18 column by gradient elution with acetonitrile-water as the mobile phase. The drift tube temperature of ELSD was set at 105 °C, and the nebulizing gas flow rate was 2.5 L min−1. The fully validated method was successfully applied to quantify the eight bioactive components in three lot products. This simple, low-cost, and reliable HPLC-DAD-ELSD method provided a new basis for assessing the quality of traditional Chinese medicinal compound preparations (TCMCPs) consisting of many bioactive components.

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This study was to examine the effects of four fungal polysaccharides, namely exo-polysaccharide (EPS), water-extracted mycelia polysaccharide (WPS), sodium hydroxideextracted mycelia polysaccharide (SPS), and hydrochloric-extracted mycelia polysaccharide (APS) obtained from the endophytic fungus Bionectra pityrodes Fat6, on the sprout growth and flavonoids production of Fagopyrum tataricum. Without obvious changes in the appearance of the sprouts, the exogenous polysaccharide elicitors notably stimulated the sprout growth and functional metabolites accumulation, and the stimulation effect was mainly depended on the polysaccharide species along with its treatment dose. With application of 150 mg/l of EPS, 150 mg/l of WPS and 200 mg/l of SPS, the total rutin and quercetin yield of buckwheat sprouts was effectively increased to 49.18 mg/(100 sprouts), 50.54 mg/(100 sprouts), and 52.27 mg/(100 sprouts), respectively. That was about 1.57- to 1.66-fold in comparison with the control culture of 31.40 mg/(100 sprouts). Moreover, the present study revealed the accumulation of bioactive flavonoids resulted from the stimulation of the phenylpropanoid pathway by fungal polysaccharide treatments. It could be an efficient strategy for improving the nutritional and functional quality of tartary buckwheat sprouts applied with specific fungal elicitors.

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Agati, G., Tattini, M. 2010. Multiple functional roles of flavonoids in photoprotection. New Phytol. 186 :786–793. Tattini M. Multiple

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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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101 105 J.B. Harborne and T.J. Mabry , The Flavonoids: Advances in Research, Chapman and Hall, London, 1982. Mabry

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. Carcinogenesis 7 1193 1196 Duthie, S. J., Johnson, W. & Dobson, V. L. (1997a): The effect of dietary flavonoids on

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