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21.
Development of a method to screen and isolate potential α‐glucosidase inhibitors from Panax japonicus C.A. Meyer by ultrafiltration,liquid chromatography,and counter‐current chromatography
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A new assay based on ultrafiltration, liquid chromatography and mass spectrometry was developed for the rapid screening and identification of the ligands for α‐glucosidase from the extract of Panax japonicus. Six saponins were identified as α‐glucosidase inhibitors. Subsequently, the specific binding ligands, namely, notoginsenoside R1, ginsenoside Rb1, chikusetsusaponin V, chikusetsusaponin IV, chikusetsusaponin IVa, and ginsenoside Rd (the purities were 94.18, 95.43, 96.09, 93.26, 94.50, 93.86%, respectively) were separated by counter‐current chromatography using two‐phase solvent systems composed of tert‐butyl methyl ether, acetonitrile, 0.1% aqueous formic acid (3.8:1.0:4.4, v/v/v) and the solvent system composed of methylene chloride, isopropanol, methanol, 0.1% aqueous formic acid (5.8:1.0:6.0:2.2, v/v/v). The results demonstrate that ultrafiltration, liquid chromatography and mass spectrometry combined with high‐speed counter‐current chromatography might provide not only a powerful tool for screening and isolating α‐glucosidase inhibitors in complex samples but also a useful platform for discovering bioactive compounds for the prevention and treatment of diabetes mellitus. 相似文献
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Min Zhou Min Xu Dong Wang Hong‐Tao Zhu Chong‐Ren Yang Ying‐Jun Zhang 《Helvetica chimica acta》2011,94(11):2010-2019
Phytochemical investigation of the rhizomes of Panax japonicus C. A. Meyer (Araliaceae) resulted in the isolation of two new dammarane‐type triterpenoid saponins, yesanchinoside R1 ( 1 ) and yesanchinoside R2 ( 2 ), together with one new natural product, 6′′′‐O‐acetylginsenoside Re ( 3 ). In addition, 25 known compounds, including 23 triterpenoid saponins, 4 – 26 , β‐sitosterol 3‐O‐β‐D ‐glucopyranoside ( 27 ), and ecdysterone ( 28 ), were also identified. The known saponins 12, 15 , and 18 – 22 were reported for the first time from the title plant. Their structures were elucidated on the basis of detailed spectroscopic analyses, including 1D‐ and 2D‐NMR techniques, as well as acidic hydrolysis. 相似文献
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采用傅里叶变换红外光谱仪的衰减全反射附件——OMNI采样器,对3种不同产地的竹节人参进行了红外光谱对比分析。结果表明,竹节人参中的红外光谱主要由皂甙类、多糖、氨基酸等物质的特征吸收峰组成。不同产地的竹节人参在1190—890cm-1区域的红外光谱吸收峰差异较显著,同时产地不同的样品其吸收峰强度亦有所不同。ATR-FTIR法简便、快速,可用于竹节人参的分析鉴别。 相似文献
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Shi Qiu Wen-zhi Yang Xiao-jian Shi Chang-liang YaoMin Yang Xuan LiuBao-hong Jiang Wan-ying Wu De-an Guo 《Analytica chimica acta》2015
Exploration of new natural compounds is of vital significance for drug discovery and development. The conventional approaches by systematic phytochemical isolation are low-efficiency and consume masses of organic solvent. This study presents an integrated strategy that combines offline comprehensive two-dimensional liquid chromatography, hybrid linear ion-trap/Orbitrap mass spectrometry, and NMR analysis (2D LC/LTQ-Orbitrap-MS/NMR), aimed to establish a green protocol for the efficient discovery of new natural molecules. A comprehensive chemical analysis of the total ginsenosides of stems and leaves of Panax ginseng (SLP), a cardiovascular disease medicine, was performed following this strategy. An offline 2D LC system was constructed with an orthogonality of 0.79 and a practical peak capacity of 11,000. The much greener UHPLC separation and LTQ-Orbitrap-MS detection by data-dependent high-energy C-trap dissociation (HCD)/dynamic exclusion were employed for separation and characterization of ginsenosides from thirteen fractionated SLP samples. Consequently, a total of 646 ginsenosides were characterized, and 427 have not been isolated from the genus of Panax L. The ginsenosides identified from SLP exhibited distinct sapogenin diversity and molecular isomerism. NMR analysis was finally employed to verify and offer complementary structural information to MS-oriented characterization. The established 2D LC/LTQ-Orbitrap-MS/NMR approach outperforms the conventional approaches in respect of significantly improved efficiency, much less use of drug materials and organic solvent. The integrated strategy enables a deep investigation on the therapeutic basis of an herbal medicine, and facilitates new compounds discovery in an efficient and environmentally friendly manner as well. 相似文献
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This study compared eight major ginsenosides (Rg1, Rg2, Rf, Re, Rd, Rc, Rb1 and Rb2) between Panax sokpayensis and Panax bipinnatifidus collected from Sikkim Himalaya, India. High-performance liquid chromatographic analysis revealed that all major ginsenosides were present in the rhizomes of P. sokpayensis except ginsenoside Rc, whereas ginsenoside Rf, Rc and Rb2 were not detected in P. bipinnatifidus. 相似文献
28.
《Journal of separation science》2018,41(17):3415-3423
A rapid analytical method was developed for the determination of 4‐methylimidazole from red ginseng products containing caramel colors by using dispersive liquid–liquid microextraction with in situ derivatization followed by gas chromatography with mass spectrometry. Chloroform and acetonitrile were selected as the extraction and dispersive solvents, and based on the extraction efficiency, their optimum volumes were 200 and 100 μL, respectively. The optimum volumes of the derivatizing agent (isobutyl chloroformate) and catalyst (pyridine), pH, and concentration of NaCl in the sample solution were determined to be 25 and 100 μL, pH 7.6, and 0% w/v, respectively. Validation of the optimized method showed good linearity (R2 > 0.999), accuracy (≥89.86%), intra‐ (≤6.70%) and interday (≤4.17%) repeatability, limit of detection (0.96 μg/L), and limit of quantification (5.79 μg/L). The validated method was applied to quantify 4‐methylimidazole in red ginseng juices and concentrates, 4‐methylimidazole was only found in red ginseng juices containing caramel colorant (42.91–2863.4 μg/L) and detected in red ginseng concentrates containing >1% caramel colorant. 相似文献
29.
人参、西洋参和三七为人参属近缘物种,形态和化学成分相似,均具有连作障碍的特性。人参属中药连作后,土壤环境逐渐变得不适宜其生长,植株长势变弱易患病,导致生长发育受到抑制,出现严重的根腐病、须根脱落,甚至植株死亡现象。而造成人参属连作障碍的主要原因之一是化感物质的自毒作用,人参残体降解物作为人参化感物质主要来源之一,会导致种子发芽率下降,种苗死亡率升高、根腐病等病害加重,最终造成连作障碍。在人参属中药连作过程中,通过化感物质与土壤交流,也会直接或间接影响土壤理化性质的变化。对人参属中药腐解化感作用的研究进展以及腐解对土壤成分的影响进行综述,以期为人参属中药腐解化感作用及土壤利用的相关研究提供借鉴。 相似文献
30.
Two new saponins were isolated from leaves of Panax quinquefolium and their structures were elucidated as 3beta, 12beta, 20S-trihydroxy-25-methoxydammar-23-ene 3-O-{[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[alpha-L-arabinopyranosyl(1-->6)]-beta-D-glucopyranoside (1) and 3beta, 20S-dihydroxy-12beta, 23R-epoxydammar-24-ene 3-O-{[beta-D-glucopyranosyl(1-->2)-beta-D-glucopyranosyl]-20-O-[beta-D-xylopyanosyl(1-->6)]-beta-D-glucopyranoside (2) on the basis of (1)D and (2)D NMR (including (1)H, (13)C-NMR, (1)H-(1)H COSY, HSQC, TOCSY, HMBC, and NOESY), ESI-MS spectrometry and chemical methods. 相似文献