Aim To establish an RP-HPLC method for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract. Methods Chromatography was carfled out on Kromasil C18 column （250 mm...Aim To establish an RP-HPLC method for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract. Methods Chromatography was carfled out on Kromasil C18 column （250 mm × 4.6 mm, 5 μm）, using THF-CH3CN-H2O-H3PO4 （30 ： 5： 125 ： 0. 1） as the mobile phase at a flow rate of 1.0 mL·min^-1. The UV detection wavelength was 270 nm. Results The linear range of 2＂-O-rhamnosyl vitexin and vitexin were 0. 106 4 μg - 2. 1280 μg （ r =0. 999 1 ） and 0. 139 2μg - 2. 784 0 μg （ r =0. 999 3 ）, respectively. The average recoveries of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf were 99.2% （ RSD = 2.80%, n = 6） and 100.6% （ RSD = 2.84%, n = 6）, respectively. Conclusion This method is reproducible, simple, precise, and rapid for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract, thereby providinge the basis for quality specification of Chinese hawthorn leaf and its extract.展开更多
[Objective]To establish the callus induction and proliferation system of the petiole of the wild European plum.[Methods]The petiole of the wild European plum was used as an explant.The effects of disinfection time,typ...[Objective]To establish the callus induction and proliferation system of the petiole of the wild European plum.[Methods]The petiole of the wild European plum was used as an explant.The effects of disinfection time,type and concentration of carbon source,dark treatment time,basic medium,growth regulator and sampling time on callus induction and petiole proliferation were studied.[Results]The best sampling time was from mid-May to mid-June.The lowest pollution rate was 3.33%when they were disinfected with 75%alcohol for 45 s and 0.1%mercuric chloride for 7 min.21 d of dark treatment was the best dark treatment time.The best formula for callus induction and proliferation was:B5+0.2 mg/L 6-BA+2 mg/L NAA+30 g/L sucrose+7 g/L agar.[Conclusion]A theoretical foundation was laid for the tissue culture and regeneration system of the wild European plum.展开更多
Eight flavonoid derivatives： rutin, quercetin-3-glucoside, quercetin, luteolin-7-glucoside, isorhmnetin-3-sulphate, kaempferol-3,7-diglucoside,＇luteolin and kaempferol have been extracted and characterized from Nipa...Eight flavonoid derivatives： rutin, quercetin-3-glucoside, quercetin, luteolin-7-glucoside, isorhmnetin-3-sulphate, kaempferol-3,7-diglucoside,＇luteolin and kaempferol have been extracted and characterized from Nipa palm. Mild extraction technique involving the use of HPLC-DAD-MS was used. The structures of the flavonoids were determined on the basis of mass spectroscopy. Separation of the crude extract by paper chromatography （PC） on forestall as solvent system gave one major yellowish brown spot which had Rf value of 3.9. The Rf value and maximum absorption from UV spectroscopy were the same as those of quercetin standard. The most prominent compound was quercetin followed by three others： kaempferol-3,7-diglucoside, luteolin-7-glucoside, and isorhmnetin-3 -sulphate.展开更多
The Fourier transform for homogeneous vector bundles over quaternion unit disk is studied, and the corresponding inversion formula and Plancherel formula are established.
文摘Aim To establish an RP-HPLC method for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract. Methods Chromatography was carfled out on Kromasil C18 column （250 mm × 4.6 mm, 5 μm）, using THF-CH3CN-H2O-H3PO4 （30 ： 5： 125 ： 0. 1） as the mobile phase at a flow rate of 1.0 mL·min^-1. The UV detection wavelength was 270 nm. Results The linear range of 2＂-O-rhamnosyl vitexin and vitexin were 0. 106 4 μg - 2. 1280 μg （ r =0. 999 1 ） and 0. 139 2μg - 2. 784 0 μg （ r =0. 999 3 ）, respectively. The average recoveries of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf were 99.2% （ RSD = 2.80%, n = 6） and 100.6% （ RSD = 2.84%, n = 6）, respectively. Conclusion This method is reproducible, simple, precise, and rapid for simultaneous determination of 2＂-O-rhamnosyl vitexin and vitexin in Chinese hawthorn leaf and its extract, thereby providinge the basis for quality specification of Chinese hawthorn leaf and its extract.
文摘[Objective]To establish the callus induction and proliferation system of the petiole of the wild European plum.[Methods]The petiole of the wild European plum was used as an explant.The effects of disinfection time,type and concentration of carbon source,dark treatment time,basic medium,growth regulator and sampling time on callus induction and petiole proliferation were studied.[Results]The best sampling time was from mid-May to mid-June.The lowest pollution rate was 3.33%when they were disinfected with 75%alcohol for 45 s and 0.1%mercuric chloride for 7 min.21 d of dark treatment was the best dark treatment time.The best formula for callus induction and proliferation was:B5+0.2 mg/L 6-BA+2 mg/L NAA+30 g/L sucrose+7 g/L agar.[Conclusion]A theoretical foundation was laid for the tissue culture and regeneration system of the wild European plum.
文摘Eight flavonoid derivatives： rutin, quercetin-3-glucoside, quercetin, luteolin-7-glucoside, isorhmnetin-3-sulphate, kaempferol-3,7-diglucoside,＇luteolin and kaempferol have been extracted and characterized from Nipa palm. Mild extraction technique involving the use of HPLC-DAD-MS was used. The structures of the flavonoids were determined on the basis of mass spectroscopy. Separation of the crude extract by paper chromatography （PC） on forestall as solvent system gave one major yellowish brown spot which had Rf value of 3.9. The Rf value and maximum absorption from UV spectroscopy were the same as those of quercetin standard. The most prominent compound was quercetin followed by three others： kaempferol-3,7-diglucoside, luteolin-7-glucoside, and isorhmnetin-3 -sulphate.
文摘The Fourier transform for homogeneous vector bundles over quaternion unit disk is studied, and the corresponding inversion formula and Plancherel formula are established.
