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111.
为了建立高质量、高分辨率人参蛋白双向电泳图谱来对人参蛋白进行功能分析与研究,提出一种利用双向梯度胶电泳技术.第一向等电聚焦电泳分离后,第二向分别采用12.5%浓度的均一胶和10%~12.5%、12.5%~15%、10%~15%三种不同浓度的SDS-PAGE梯度胶来获取人参蛋白双向电泳图谱,并利用Image Scanner和Image Master 2D Platinum version6.0对图像进行扫描及比较分析.结果表明,采用10%~15%浓度梯度胶获得双向电泳图谱中蛋白点圆滑、形状规则,分离效果好|有效地减少了人参中高丰度蛋白对中低丰度蛋白的掩盖,Mw>75 kDa的可检测到的低丰度和大分子量蛋白点数明显增加.研究结果为高质量人参蛋白表达图谱的建立奠定了良好的实验基础,同时也为其它五加科植物蛋白质组学研究工作的开展提供了方法学上的指导. 相似文献
112.
Meng Fang Yuqing Meng Zhiyong Du Mengqiu Guo Yong Jiang Pengfei Tu Kun Hua Yingyuan Lu Xiaoyu Guo 《Molecules (Basel, Switzerland)》2022,27(24)
Notoginseng and safflower are commonly used traditional Chinese medicines for benefiting qi and activating blood circulation. A previous study by our group showed that the compatibility of the effective components of total saponins of notoginseng (NS) and total flavonoids of safflower (SF), named NS–SF, had a preventive effect on isoproterenol (ISO)-induced myocardial infarction (MI) in rats. However, the therapeutic effect on MI and the synergistic mechanism of NS–SF are still unclear. Therefore, integrated metabolomics, combined with immunohistochemistry and other pharmacological methods, was used to systematically research the therapeutic effect of NS–SF on MI rats and the synergistic mechanism of NS and SF. Compared to NS and SF, the results demonstrated that NS–SF exhibited a significantly better role in ameliorating myocardial damage, apoptosis, easing oxidative stress and anti-inflammation. NS–SF showed a more significant regulatory effect on metabolites involved in sphingolipid metabolism, glycine, serine, and threonine metabolism, primary bile acid biosynthesis, aminoacyl-tRNA biosynthesis, and tricarboxylic acid cycle, such as sphingosine, lysophosphatidylcholine (18:0), lysophosphatidylethanolamine (22:5/0:0), chenodeoxycholic acid, L-valine, glycine, and succinate, than NS or SF alone, indicating that NS and SF produced a synergistic effect on the treatment of MI. This study will provide a theoretical basis for the clinical development of NS–SF. 相似文献
113.
Hongwei Kong Mei Wang Koen Venema Annet Maathuis Rob van der Heijden Jan van der Greef Guowang Xu Thomas Hankemeier 《Journal of chromatography. A》2009,1216(11):2195-2203
A high-performance liquid chromatography–high resolution Fourier transform ion cyclotron resonance mass spectrometry (HPLC–FTICR-MS) method was developed to investigate the metabolism of ginsenosides in in vitro models of the gastro-intestinal tract. The metabolites were identified by high-resolution tandem mass spectrometry. Degradation and bioconversion routes of the different ginsenosides at acidic (gastric) conditions and in the presence of intestinal microbiota were elaborated. Besides hydrolysis (deglycosylation) also hydration reactions occurred at acidic conditions. The results illustrate the value of metabolite profiling by HPLC–FTICR-MS for understanding of the mechanisms in bioavailability of herbal drugs and their metabolites. 相似文献
114.
鲜人参中2种丙二酰基人参皂苷的分离鉴定 总被引:7,自引:0,他引:7
采用硅胶柱层析方法,流动相分别为氯仿-甲醇-水(65∶35∶10,V/V)、氯仿-甲醇-水(6∶4∶1)和正丁醇-乙酸乙脂-甲醇-水(4∶2∶1∶1)和高效液相(Nuc leosil C18(250 mm×10 mm,5μm)色谱柱;流动相为己腈-水(75∶25);流速为3.0 mL/m in;柱温30℃;检测波长203 nm。从中国鲜人参中分离得到丙二酰基人参皂苷R c和丙二酰基人参皂苷Rb2,并通过其理化性质、红外光谱、质谱和核磁共振谱对化合物的结构进行了鉴定,证明其结构分别为3-O-[6-O-丙二单酰-β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖]-20-O-[α-L-阿拉伯呋喃糖(1→6)-β-D-葡萄吡喃糖]-20(S)-原人参二醇和3-O-[6-O-丙二单酰-β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖]-20-O-[α-L-阿拉伯吡喃糖(1→6)-β-D-葡萄吡喃糖]-20(S)-原人参二醇;丙二酰基人参皂苷R c为首次从中国鲜人参中分得。 相似文献
115.
The present work describes the systematic development of a robust, precise, and rapid reversed-phase liquid chromatography method for the simultaneous analysis of five chemical components in Panax notoginseng saponins (PNS) using quality by design (QbD). The method was developed in two main phases: screening and optimization. During the screening phase, the most suitable stationary phase, column temperature, and flow rate were identified, while the secondary influential parameters, such as the gradient slope, the initial concentration of acetonitrile, and the initial isocratic hold of the gradient elution system were fine-tuned in the later optimization phase. In this phase, a 17-run experiment was used to examine multifactorial effects of these parameters on the critical resolution, analysis time, and peak symmetry. The Monte Carlo simulation method was successfully used to build the chromatographic design space and the process capability index Cp was introduced to evaluate the robustness of the design space. At last, the verification experiment was performed within the working design space by the accuracy profile methodology and model was found to be accurate. A robust combination of separation conditions predicted in the design space was obtained with the gradient slope of 1.6% · min?1, the initial concentration of acetonitrile of 20%, and the initial isocratic hold of 20 min, and the total analysis time was no more than 40 min. The results demonstrated that rapid separation of five components of PNS herbal extract could be achieved on the chromatographic column packed with narrow size particles at backpressures available in ordinary high performance liquid chromatography (HPLC) instruments. 相似文献
116.
从新鲜人参根中分离得到了1个新化合物, 根据理化性质和谱学方法并与文献报道的相关化合物的数据进行比较, 鉴定其结构为丙二酰基三七人参皂苷-R4(Malonyl-notoginsenoside-R4, 1). 相似文献
117.
A surface flowing mode sample holder was designed as an alternative sampling strategy for direct analysis in real time mass spectrometry (DART-MS). With the sample holder, the on-line coupling of macroporous resin column chromatography with DART-MS was explored and the new system was employed to monitor the column chromatography elution process of Panax notoginseng. The effluent from macroporous resin column was first diluted and mixed with a derivatization reagent on-line, and the mixture was then directly transferred into the ionization region of DART-MS by the sample holder. Notoginsenosides were methylated and ionized in a metastable helium gas stream, and was introduced into MS for detection. The on-line system showed reasonable repeatability with a relative standard deviation of 12.3% for the peak area. Three notoginsenosides, i.e. notoginsenoside R1, ginsenoside Rb1 and ginsenoside Rg1, were simultaneously determined during the eluting process. The alteration of the chemical composition in the effluent was accurately identified in 9 min, agreeing well with the off-line analysis. The presented technique is more convenient compared to the traditional UPLC method. These results suggest that the surface flowing mode DART-MS has a good potential for the on-line process monitoring in the pharmaceutical industry. 相似文献
118.
中药材三七中皂苷类成分的近红外光谱快速无损分析新方法 总被引:23,自引:0,他引:23
提出了用近红外漫反射光谱快速无损测定三七中皂苷类成分的新方法采用 HPLC分析了中药材三七固皂昔R_1,人参皂苷Hg_1,Rb_1和Rd的含量,用吸附树脂 比色法测定了三七总皂苷(PNS)的含量,共获得R_1,Bg_1,Rb_1,Rd,PNS的含 量范围分别为1,58-5.08,21,68-46.13,11.46-40.41粉.在3500-1100cm~(-1) 扫描样品,以交叉验证误差均方根(RMsECV)为指标,通过筛选,近红外波段和光 谱预处理方法.采用偏最小二乘算法建立了近红外光谱与5个组分PHLC分析值之间 的校正模型,预测了8个未知样本.R_1,Rg_1,Rb_1,Rd及PNS校正模型的RMSECV 分别为0.40,1.47,1.94,0RMSEP分别为0.53,3.15,2.14,0.70,9.03. 该方法快速无损,结果可靠,为中药材复杂体系中化学组分的测定提供了新的绿色 分析手段. 相似文献
119.
120.
《Magnetic resonance in chemistry : MRC》2002,40(7):483-488
Nine protopanaxatriol glycosides isolated from mild acid hydrolysis products of crude root saponins of Panax notoginseng were identified as 20(R)‐ginsenoside‐Rh1, 20(S)‐ginsenoside‐Rh1, ginsenoside‐Rg1, ‐Re and ‐Rg2, notoginsenoside‐R2 and ‐R1, a mixture of 25‐hydroxy‐20(S)‐ginsenoside‐Rh1 and its C‐20 (R) epimer, ginsenoside‐Rh4. The complete assignments of the 1H and 13C NMR chemical shifts for these glycosides were obtained by means of 2D NMR techniques, including 1H–1H COSY, ROESY, HMQC, HMBC and HMQC‐TOCSY spectra. The glycosylation shift effect of protopanaxatriol and the differences in chemical shifts between 20(R)‐ and 20(S)‐protopanaxatriol isomers are also discussed. Except for ginsenoside‐Re and ‐Rg2, complete NMR assignments of the other seven glycosides are reported for the first time. Copyright © 2002 John Wiley & Sons, Ltd. 相似文献