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排序方式: 共有111条查询结果,搜索用时 15 毫秒
1.
研究了利用源内碰撞诱导解离(in-source collision—induced dissociation)的高效液相色谱-大气压化学电离质谱(HPLC—APCI/MS)获取人参和西洋参的化学标志物——人参皂甙Rf和拟人参皂甙F11的特征结构信息及鉴别人参和西洋参的方法。在乙腈-水梯度洗脱反相液相色谱及源内碰撞诱导解离条件下,能获得人参皂甙Rf和拟人参皂甙F11的母核离子及去糖基离子的源内碰撞诱导解离谱,从其差别能清楚区分这对同分异构体。本方法对人参皂甙Rf和拟人参皂甙F11的检出限能达到10^-7g柱上样量,简单、快速,单次质谱实验就能鉴别人参和西洋参。 相似文献
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以三七茎叶提取物为原料,采用反相液相色谱柱进行分离纯化,通过考察流动相组成、配比、上样量和流量对分离效果的影响,确定了适宜的工艺操作条件.在此奈件下得到了人参皂苷Rb3,纯度达99.37%.进而以提纯的皂苷单体为标准品,采用外标法对其进行定量分析,并测得原料中含有人参皂苷Rb3质量分数为38.25%.同时又采用了高效液相色谱-质谱联用技术,建立了三七茎叶提取物的指纹图谱. 相似文献
3.
Bo-Yang Hsu Chen-Te Jen Baskaran Stephen Inbaraj Bing-Huei Chen 《Molecules (Basel, Switzerland)》2022,27(10)
Ginseng (Panax quinquefolius), a popular herbal and nutritional supplement consumed worldwide, has been demonstrated to possess vital biological activities, which can be attributed to the presence of ginsenosides. However, the presence of ginsenosides in ginseng root residue, a by-product obtained during processing of ginseng beverage, remains unexplored. The objectives of this study were to develop a high-performance liquid chromatography-photodiode array detection-mass spectrometry (HPLC-DAD-ESI-MS) and an ultra-high-performance-liquid-chromatography-tandem mass spectrometry (UPLC-HRMS-MS/MS) method for the comparison of ginsenoside analysis in ginseng root residue. Results showed that by employing a Supelco Ascentis Express C18 column (150 × 4.6 mm ID, particle size 2.7 μm) and a gradient mobile phase of deionized water and acetonitrile with a flow rate at 1 mL/min and detection at 205 nm, a total of 10 ginsenosides, including internal standard saikosaponin A, were separated within 18 min and detected by HPLC-DAD-ESI-MS. Whereas with UPLC-HRMS-MS/MS, all the 10 ginsenosides were separated within six minutes by using an Acquity UPLC BEH C18 column (50 × 2.1 mm ID, particle size 1.7 μm, 130 Å) and a gradient mobile phase of ammonium acetate and acetonitrile with column temperature at 50 °C, flow rate at 0.4 mL/min and detection by selected reaction monitoring (SRM) mode. High accuracy and precision was shown, with limit of quantitation (LOQ) ranging from 0.2–1.9 μg/g for HPLC-DAD-ESI-MS and 0.269–6.640 ng/g for UPLC-HRMS-MS/MS. The contents of nine ginsenosides in the ginseng root residue ranged from <LOQ-26.39 mg/g by HPLC-DAD-ESI-MS and <LOQ-21.25 mg/g by UPLC-HRMS-MS/MS, with a total amount of 38.37 and 34.71 mg/g, respectively. 相似文献
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CBN中葛根素、人参皂甙Rg1在正常和脑缺血再灌大鼠体内药代动力学比较 总被引:5,自引:0,他引:5
目的:探讨CBN中葛根素和人参皂甙Rg1在正常和脑缺血再灌大鼠体内的药代动力学过程。方法:脑缺血再灌组大鼠结扎双侧颈总动脉不完全脑缺血30分钟,复灌同时股静脉注射100mg·Kg-1药物。正常组注射等剂量药物。HPLC法测定给药后不同时间点血浆样品中葛根素和人参皂甙Rg1的含量,并作动力学计算。结果:CBN中葛根素在正常大鼠体内为一室模型,半衰期是17.8min;在脑缺血再灌大鼠体内为二室模型,分布和消除半衰期分别是8.0min和38.4min;药时曲线下面积(AUC,mg·L-1·min),表观分布容积(Vdss·L·kg-1),平均驻留时间(MRTmin)正常组分别为:744,4.18,26.0;脑缺血再灌组分别为:3015,1.39,40.0。人参皂甙Rg1在正常大鼠和脑缺血再灌大鼠体内为二室模型,分布和消除相半衰期分别为8.2,2,700.8min;18.6,4297min。药时曲线下面积(AUC,mg·L-1·min),表观分布容积(Vdss·L·kg-1),平均驻留时间(MRTmin)正常组分别为:531.5,7.05,164.7;脑缺血再灌组分别为:1678,2.39,73.3。结论:静脉注射CBN后,葛根素和人参皂甙Rg1在缺血再灌大鼠体内的消除时间较在正常大鼠体内延长。 相似文献
6.
Jiping Huo Hongyun Wang Pei Hu Pingya Li Jinping Liu Ji Jiang 《Biomedical chromatography : BMC》2013,27(12):1701-1707
A specific, sensitive and rapid method based on high performance liquid chromatography coupled to tandem mass spectrometry (HPLC‐MS/MS) was developed for the determination of pseudo‐ginsenoside GQ in human plasma. Liquid–liquid extraction was used to isolate the analyte from biological matrix followed by injection of the extracts onto a C8 column with isocratic elution. Detection was carried out on a triple quadrupole tandem mass spectrometer (API‐4000 system) in multiple reaction monitoring mode using negative electrospray ionization. The mobile phase consisted of methanol–10 mm ammonium acetate (90:10, v/v) and the flow rate was 0.3 mL/min. The method was validated over the concentration range of 5.0–5000.0 ng/mL for plasma. Inter‐ and intra‐day precisions (relative standard deviation) were all within 15% and the accuracy (relative error) was ≤9.4%. The lower limit of quantitation was 5.0 ng/mL. The pseudo‐ginsenoside GQ was stable after 8 h at room temperature, 24 h at autosampler and three freeze–thaw cycles (from ?30 to 25 °C). The method was successfully applied to the pharmacokinetic study of pseudo‐ginsenoside GQ in healthy Chinese volunteers. Copyright © 2013 John Wiley & Sons, Ltd. 相似文献
7.
Tissue distribution and excretion study of neopanaxadiol in rats by ultra‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry 下载免费PDF全文
Cong Geng Jian‐yuan Yin Xiu‐hua Yu Jing‐yan Liu Yu‐xia Yang De‐ya Sun Qin Meng Zhong‐lin Wei Ji‐hua Liu 《Biomedical chromatography : BMC》2015,29(3):333-340
Neopanaxadiol (NPD), a major ginsenoside in Panax ginseng C. A. Meyer (Araliaceae), was reported to have neuroprotective effect. In this study, a method of ultra‐performance liquid chromatography quadrupole time‐of‐flight mass spectrometry (UPLC/QTOF‐MS) was developed and validated for quantitative analysis of NPD in tissues, urine and feces, using liquid–liquid extraction (LLE) to isolate NPD from different biological samples, and chromatographic separation was performed on an Agilent Zorbax Stable Bond C18 (2.1 × 50 mm, 1.8 µm) column with 0.1% formic acid in water and acetonitrile. All standard calibration curves were linear (all r2 > 0.995) within the test range. After oral administration, NPD was extensively distributed to most of the tissues without long‐term accumulation. The higher levels were observed in stomach and intestine, followed by kidney and liver. Approximately 64.56 ± 20.32% of administered dose in feces and 0.0233 ± 0.0356% in urine were found within 96 h, which indicated that the major elimination route was fecal excretion. This analytical method was applied to the study of NPD distribution and excretion in rats after oral intake for the first time. The results we found here are helpful for us to understand the pharmacological effects of NPD, as well as its toxicity. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
8.
微波提取人参中活性成分人参皂苷的研究 总被引:2,自引:0,他引:2
研究了应用微波提取西洋参干燥根中人参皂苷的最佳工艺.采用正交试验进行优化,分光光度法测定人参总皂苷的含量.结果表明,用微波提取人参皂苷的最佳工艺条件为:微波功率300 W,固液比1∶20,提取温度60℃,提取4次,每次提取3 m in.在此条件下,人参皂苷的提取得率高达5.53%.微波提取人参皂苷工艺具有得率高、时间短、能耗低、环保等优点. 相似文献
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三七根茎的化学成分研究(Ⅱ) 总被引:6,自引:0,他引:6
研究三七[Panax notoginseng(Burk.)F.H.Chen]根茎的化学成分.利用D101大孔吸附树脂柱、硅胶柱、RP-8和RP-18柱进行化合物的分离纯化,根据其理化性质和光谱数据进行结构鉴定.从三七根茎部分分离鉴定出5个化合物,分别为人参皂苷三七皂苷T5(Notoginsenoside T5,Ⅰ),人参皂苷F1(Gin senoside F1,Ⅱ),人参皂苷F2(Ginsenoside F2,Ⅲ),三七皂苷E(Notoginsenoside E,Ⅳ),人参皂苷Ⅱ(GinsenosideⅡ,Ⅴ).Ⅴ为首次从该植物中分离获得,Ⅰ~Ⅳ为首次从该植物根茎中分离获得. 相似文献