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141.
An HPLC-APCI-MS method for the identification of ginsenosides in Panax quinquefolium has been developed. HPLC-APCI-MS could effectively identify ocotillol, protopanaxadiol, protopanaxatriol and oleanane-type ginsenosides in a single MS experiment since [M-H] ions and characteristic thermal degradation ions of ginsenosides could be simultaneously observed under negative and positive ionization conditions. Nine ocotillol-type ginsenosides including 24(R)-pseudoginsenoside F11 were firstly identified and a total of 30 ginsenosides were identified in Panax quinquefolium. The ginsenoside profile differences between Chinese and American P. quinquefolium were investigated by HPLC-APCI-MS.  相似文献   
142.
Further phytochemical investigation of the steaming treated roots of Panax notoginseng (Araliaceae) led to the identification of two new dammarane-type triterpenoid saponins, notoginsenoside SP20 (1) and SP21 (2). In addition, a pair of new phenolic glycosides (3a and 3b) was also isolated together with two known compounds. Their structures were elucidated by HRESIMS, 1D- and 2D-NMR spectra. Compounds 1 and 2 showed no in vitro cytotoxicity against five human cancer cell lines (HL-60, SMMC-7712, A-549, MCF-9 and SW480).  相似文献   
143.
Two new acetylated ginsenosides from the roots of Panax quinquefolium   总被引:1,自引:0,他引:1  
Two new acetylated ginsenosides, 20(S)-protopanaxatriol-6-O-α-L-rhamnopyranosyl (1 → 2)-β-D-6'-O-acetylglucopyranoside (1) and 20(R)-protopanaxatrol-6-O-α-L-rhamnopyranosyl (1 → 2)-β-o-6'-O-acetylglucopyranoside (2), were isolated from the roots of Panax quinquefolium. The structures were elucidated on the basis of spectroscopic techniques and chemical means.  相似文献   
144.
A high‐performance anion‐exchange chromatography coupled with diode array detection method was developed for the determination of dencichine in Panax notoginseng and related species. The analysis was performed on an Eprogen Synchropak WAX column (4.6 × 250 mm, 6 μm) with 50 mM NaH2PO4 aqueous solution isocratic elution. The method was validated in terms of linearity, sensitivity, precision, stability, and accuracy. It was found that the calibration curve for dencichine showed good linearity (R2 = 0.9999) within the test range. The LOD and LOQ were 0.77 and 3.06 ng, respectively. The RSD for intra‐ and interday repeatability was 0.2 and 0.5%, respectively. The test solution of dencichine is stable at least for three days at room temperature and for seven days at 4°C. The mean recovery of dencichine was 102.0%. The established method was successfully applied to determine dencichine in the raw root of P. nogoginseng, P. ginseng, and P. quinquefolium as well as the steamed root of P. notoginseng. Compared with previous reports, this method is sensitive, selective, and accurate, which is helpful to evaluate the quality of P. notoginseng and related species.  相似文献   
145.
<正>One new triterpene saponin was isolated from Panaxjaponicus C.A.Meyer var major(Burk.) C.Y.Wu et K.M.Feng,and established as oleanolic acid 3-O-[β-D-glucopyranosyl-(1→2)-β-D-glucuronopyranosyl-6'-O-n-butyl ester]which showed moderate antitumor activities against the A2780 cells and OVCAR-3 cells.Its structure was established by means of spectral data, particularly NMR,including HSQC and HMBC techniques.  相似文献   
146.
采用泡沫浮选法对三七提取液中的人参皂苷Rg1、Re、Rb1和Rd进行了分离富集,并用高效液相色谱法分别测定了含量.考察了浮选液浓度、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响.结果表明:泡沫浮选法对4种皂苷均有较好的分离富集效果,尤其是对人参二醇型皂苷(Rb1,Rd)效果更为明显.当浮选液浓度为2.0 mg/mL,pH值为2~3,氮气流速为20 mL/min,浮选时间10 min,电解质氯化钠浓度0.20 mol/L,泡沫浮选效果最佳.  相似文献   
147.
A high performance liquid chromatography(HPLC) with UV detection was established for simultaneous determination of saponins in the leaf of Panax ginseng C. A. Mey. Nine ginsenosides(Rb1,Rb2,Rb3,Rc,Rd,F1,F2,F3,F5) and notoginsenoside Fe(NFe) were studied. Among the saponins,the ginsenosides F1,F2,F3,F5 and NFe were determined by HPLC-UV method for the first time. The determination of the ginsenosides via the HPLC-UV method was performed on a reversed-phase C18 column with gradient elution in 40 min. The line...  相似文献   
148.
A new ceramide(1) was isolated from transgenic crown galls of Panax quinquefolium.The structure was elucidated as(2S,3S, 4R,20E)-2-[(2′R)-2′-hydroxylpalmitoylamino]- 20- hexacosene- 1,3,4-triol on the basis of spectroscopic and chemical methods.  相似文献   
149.
A new panaxadiol(compound 1) was obtained from the acid hydrolysate of the total ginsenosides of Panax ginseng C.A.Meyer (Araliaceae).On the basis of spectroscopic data and single-crystal X-ray diffraction data,its chemical structure was elucidated to be dammar-(E)-20(22)-ene-3β,12β,25-triol.  相似文献   
150.
A new HPLC coupled with evaporative light scattering detection (ELSD) method was developed for simultaneous determination of 11 major triterpene saponins, namely notoginsenoside R1 (1), ginsenosides Rg1 (2), Re (3), Rf(4), Rb1 (5), Rg2 (6), Rc (7), Rb2 (8), Rb3 (9), Rd (10), and Rg3 (11) in Panax notoginseng, a commonly used traditional Chinese medicine (TCM). Pressurized liquid extraction (PLE) was employed for sample preparation, and the analysis was achieved using a Zorbax ODS C18 column eluted with gradient water-ACN in 60 min. The drift tube temperature of ELSD was set at 60 degrees C, and nitrogen flowrate was at 1.4 L/min. The method provided good repeatability and sensitivity for quantification of 11 saponins with overall precision (including intra- and interday) and LOD of less than 2.9% (RSD) and 98 ng, respectively. The validated method was successfully applied to quantify 11 saponins in 28 samples of P. notoginseng collected in different places, which is helpful to control the quality of P. notoginseng and its related products.  相似文献   
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