Herba Epimedii is the dried above-ground part of the genus Epimedium. Several herbs belonging to the genus Epimedium have been used in many variations of preparations and formulas for treating a wide range of diseases...Herba Epimedii is the dried above-ground part of the genus Epimedium. Several herbs belonging to the genus Epimedium have been used in many variations of preparations and formulas for treating a wide range of diseases especially reinforcing Yang and toning the kidney by Chinese physicians for centuries[1,2]. More than 130 chemical constituents have been discovered and classified into many different chemical subgroups. Nearly half of these constituents belong to flavonoid glycosides and have been considered as the major active components in the Epimedium species. Icariin is thought to be the marker constituent of the genus because every Epimedium species contains it. The pharmaceutical effects of Epimedium species have been tested in various biological systems. It has been shown that the single constituent has less activity than that of decoctions, composite preparations or extracts of Epimedium. Therefore, it is necessary for deciphering the ensemble of the active constituents and establishing the fingerprint chromatograms of Herba Epimedii.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 present study aimed at identifying potential lead compounds for diabetes mellitus drug discovery. We developed a novel method involving centrifugal ultrafiltration separation subsequent liquid chromatography with ...The present study aimed at identifying potential lead compounds for diabetes mellitus drug discovery. We developed a novel method involving centrifugal ultrafiltration separation subsequent liquid chromatography with quadrupole time of flight tandem mass spectrometry （LC-Q/TOF-MS/MS） determination to screen a-glucosidase inhibitors in complex Scutellaria baicalensis Georgi （SBG） extract. By adding a second filter to the screening process, the level of non-specific binding of Compounds 1, 3, 10 and 11 was significantly decreased, and the level of non-specific binding of Compounds 5 and 15 also was reduced. As a result, five flavonoids identified as baicalein, baicalein, wogonin, chrysin, and oroxylin A, were rapidly found to interact with α-glucosidase and possess potent anti-a-glueosidase aetivity in vitro. Specific binding of ligands to a-glucosidase was demonstrated though the proposed method and the ligands could be ranked in order of affinity for α-glucosidase, which were corresponded to the order of inhibitory activity in vitro. In conclusion, our results indicated that the developed method is a rapid and effective screening method for rat intestinal α-glucosidase inhibitors from complex herbal medicines such as SBG.展开更多
文摘Herba Epimedii is the dried above-ground part of the genus Epimedium. Several herbs belonging to the genus Epimedium have been used in many variations of preparations and formulas for treating a wide range of diseases especially reinforcing Yang and toning the kidney by Chinese physicians for centuries[1,2]. More than 130 chemical constituents have been discovered and classified into many different chemical subgroups. Nearly half of these constituents belong to flavonoid glycosides and have been considered as the major active components in the Epimedium species. Icariin is thought to be the marker constituent of the genus because every Epimedium species contains it. The pharmaceutical effects of Epimedium species have been tested in various biological systems. It has been shown that the single constituent has less activity than that of decoctions, composite preparations or extracts of Epimedium. Therefore, it is necessary for deciphering the ensemble of the active constituents and establishing the fingerprint chromatograms of Herba Epimedii.
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.
基金supported by the National Key Scientific and Technological Special Projects(2012ZX09103-101-007)the Program for Changjiang Scholars and Innovative Research Team in University(PCSIRT-IRT1193)the Project Funded by the Priority Academic Program Development of Jiangsu Higher Education Institutions(PAPD)
文摘The present study aimed at identifying potential lead compounds for diabetes mellitus drug discovery. We developed a novel method involving centrifugal ultrafiltration separation subsequent liquid chromatography with quadrupole time of flight tandem mass spectrometry （LC-Q/TOF-MS/MS） determination to screen a-glucosidase inhibitors in complex Scutellaria baicalensis Georgi （SBG） extract. By adding a second filter to the screening process, the level of non-specific binding of Compounds 1, 3, 10 and 11 was significantly decreased, and the level of non-specific binding of Compounds 5 and 15 also was reduced. As a result, five flavonoids identified as baicalein, baicalein, wogonin, chrysin, and oroxylin A, were rapidly found to interact with α-glucosidase and possess potent anti-a-glueosidase aetivity in vitro. Specific binding of ligands to a-glucosidase was demonstrated though the proposed method and the ligands could be ranked in order of affinity for α-glucosidase, which were corresponded to the order of inhibitory activity in vitro. In conclusion, our results indicated that the developed method is a rapid and effective screening method for rat intestinal α-glucosidase inhibitors from complex herbal medicines such as SBG.
