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31.
RP-HPLC测定大别山区不同产地天麻药材中天麻素含量研究   总被引:1,自引:0,他引:1  
忻晹  陈龙胜  陈涛  蔡群兴  周斌 《光谱实验室》2005,22(6):1185-1187
采用RP-HPLC外标曲线法测定了天麻原药材中天麻素含量,色谱柱为Phenomenex-C18(4.6mm×250mm,5μm);流动相乙腈-水(5∶95);检测波长225nm。流速0.5mL·min-1:柱温27℃。结果表明天麻素在0.1000—0.6000μg呈良好线性关系,r=0.9997,平均加样回收率为99.53%,RSD为1.7%。方法灵敏、快速、准确,可用于天麻中天麻素含量的测定。  相似文献   
32.
研究了离子液体分散液相微萃取(ILDLPME)机理, 建立了简单、快速、灵敏的ILDLPME-HPLC(高效液相色谱)同时测定中药白附子中5种低丰度苯丙烯酸类化合物含量的方法, 对不同产地白附子的质量进行了比较和评价. 在最佳的ILDLPME-HPLC条件下, 测得咖啡酸的线性范围为1.28×10-3~2.60 μg/mL, 对羟基桂皮酸及阿魏酸的线性范围为1.28×10-4~2.60 μg/mL, 桂皮酸及对甲氧基桂皮酸的线性范围为1.28×10-3~4.00 μg/mL, 检出限分别为0.13, 0.01, 0.01, 0.13和0.13 ng/mL, 日内精密度RSD<7.9%, 日间精密度RSD<9.7%, 药材中分析物的回收率在86.9%~112.6%之间, ILDLPME 对5种分析物的富集倍数分别在56.0~159.3倍之间. 结合5种苯丙烯酸类化合物ILDLPME萃取前后紫外光谱的变化, 提出了ILDLPME萃取苯丙烯酸羧基-离子液体电荷转移超分子(CTSMCIL)机理. 本研究为建立中药白附子的质量控制方法提供了理论依据和实验基础.  相似文献   
33.
A novel capillary electrophoresis method for simultaneous determination of Cu and Pb has been developed in this paper.Cu(Ⅱ) and Pb(Ⅱ) ions were reacted with ABEDTA to form complex to achieve an ideal sensitivity of heavy metal complexes.The digestion solution of Rhizoma coptidis drug sample was purified by neutral Al2O3 column chromatography and the chromatographic behavior of metal-L complexes was investigated.The calibration curve was linear in the range of 5-60μg/mL for Cu2+ and 5-25μg/mL for Pb2+ with the correlation coefficients 0.9970 and 0.9972 for each(n = 5).The average recoveries were 86.2%for Pb and 90.1%for Cu,while the relative standard deviations were 5.1%and 3.6%respectively.The method was successfully applied to determine Cu and Pb in R.coptidis drug samples.  相似文献   
34.
Atractylenolide II (AII) and atractylenolide III (AIII) are the major active components in Atractylodes Macrocephala Rhizoma (AMR). In this study, a sensitive, rapid and selective liquid chromatography–tandem mass spectrometry (LC‐MS/MS) method was developed and validated for the simultaneous determination of AII and AIII in rat plasma using loliolide as internal standard (IS). After protein precipitation with ethyl acetate, the analytes were injected into an LC‐MS/MS system for quantification. Chromatography was performed using a C18 column, eluting with water and acetonitrile (45:55, v/v) at 0.2 mL/min. All analytes including IS were monitored under positive ionization conditions by multiple reaction monitoring with an electrospray ionization source. The validated method was successfully applied to the pharmacokinetic study of AII and AIII in rat plasma after oral administration of AMR extract. The results provided a meaningful basis for evaluating the clinical applications of traditional Chinese medicine. Copyright © 2012 John Wiley & Sons, Ltd.  相似文献   
35.
《Analytical letters》2012,45(16):2597-2609
A multistep infrared macro-fingerprint method was applied to identify two Chinese herbal drugs, Rhizoma Curcumas Longae (RCL) and Radix Curcumae (RC). Fourier transform infrared (FT-IR) spectra of the two were similar to each other and consistent with the 11 peaks of the spectrum of starch. RCL had a characteristic absorption peak at approximately 1514 cm?1 that correlated to the strong peak near 1509 cm?1 of curcumin. Between 900 cm?1–1700 cm?1 of the second derivative infrared (SD-IR) spectra, with higher resolution, RCL, and curcumin had 10 common peaks. In the FT-IR and SD-IR spectra of the ethanol extract, the spectra of the RCL extract and curcumin were similar, but RC was different. According to the fingerprint characteristics of the infrared spectra for RC and its extracts, the strongest peak at 1055 cm?1; the C-O absorption peaks at 1124 cm?1, 1106 cm?1, and 996 cm?1; and the strong methylene peaks at 2925 cm?1 and 2853 cm?1 suggest that RC contains more saccharides. In the range of 1350 cm?1–1700 cm?1, RCL and RC had similar two-dimensional infrared (2D-IR) correlation spectra. Both of them had three autopeaks, but the autopeaks were located at 1458 cm?1, 1560 cm?1, and 1641 cm?1 for RCL and 1458 cm?1, 1560 cm?1, and 1669 cm?1 for RC, suggested that the aromatic components of the two were not identical. The average correlation for the 18 RCL and 18 RC samples were 0.9906 and 0.9878, respectively, and this method achieves a good classification of the sample type.  相似文献   
36.
COVID-19, resulting from infection by the SARS-CoV-2 virus, caused a contagious pandemic. Even with the current vaccines, there is still an urgent need to develop effective pharmacological treatments against this deadly disease. Here, we show that the water and ethanol extracts of the root and rhizome of Polygonum cuspidatum (Polygoni Cuspidati Rhizoma et Radix), a common Chinese herbal medicine, blocked the entry of wild-type and the omicron variant of the SARS-CoV-2 pseudotyped virus into fibroblasts or zebrafish larvae, with IC50 values ranging from 0.015 to 0.04 mg/mL. The extracts were shown to inhibit various aspects of the pseudovirus entry, including the interaction between the spike protein (S-protein) and the angiotensin-converting enzyme II (ACE2) receptor, and the 3CL protease activity. Out of the chemical compounds tested in this report, gallic acid, a phytochemical in P. cuspidatum, was shown to have a significant anti-viral effect. Therefore, this might be responsible, at least in part, for the anti-viral efficacy of the herbal extract. Together, our data suggest that the extracts of P. cuspidatum inhibit the entry of wild-type and the omicron variant of SARS-CoV-2, and so they could be considered as potent treatments against COVID-19.  相似文献   
37.
Rhizoma Dioscoreae Makino (RDM) is effective in treating gouty arthritis (GA) and hyperuricacidemia, especially in promoting uric acid excretion and reducing the inflammatory reaction. Bioactive constituents in RDM are mainly steroidal saponins such as dioscin, trillin, protodioscin and protogracillin. However, the mechanism of its anti-GA action is still unclear, owing to the complex pathological and physiological characteristics of GA, and integration of RDM with multiple components, multiple targets and multiple pathways. Herein, a GA rat model was induced with monosodium urate (MSU), and RDM reduced inflammation of rat synovium tissue. Through metabolomics analysis, 35 potential biomarkers with significant changes involved in the pathogenesis of GA induced by MSU were identified, and perturbations were restored after RDM treatment. The most correlated pathways involved in d -galactose, d -mannose, d -glucose, myoinositol, Phosphatidylcholine (PC) (16:0/16:0), LysoPC (15:0), phosphatidic acid (PA) [18:1(9Z)/18:1(11Z)] and glutathione induced by MSU were galactose metabolism, inositol phosphate metabolism, glycerophospholipid metabolism and glutathione metabolism, and the derivations of all those biomarkers could be regulated by RDM treatment. RDM has a therapeutic effect on GA by intervening in changes in endogenous metabolisms and the related metabolic pathways.  相似文献   
38.
为了建立黄连色度测量方法并分析其与有效成分含量之间的相关性,应用灰色关联分析(GRA)与主成分分析(PCA)对不同产地黄连药材进行质量评价。收集了来自15个不同产区黄连药材,依据国际照明委员会CIE L*a*b*数字化系统,采用分光测色计测定15批黄连药材色度值,采用高效液相色谱(HPLC)测定表小檗碱、黄连碱、巴马汀和盐酸小檗碱4种生物碱含量,并运用SPSS 23.0软件对色度与生物碱含量进行相关性分析。将黄连药材中生物碱类成分含量、药材水分、灰分、浸出物含量及色度值作为考察指标,采用GRA法构建黄连质量评价模型并采用SIMCA-P 14.1软件进行PCA及正交偏最小二乘法分析;结果表明,色度测量方法准确可靠;相关性分析结果显示,黄连色度L*a*b*Eab* (总色度值)值与表小檗碱、黄连碱、巴马汀和盐酸小檗碱的含量均有显著相关性。GRA分析结果显示,产地为重庆市的黄连与最优参考序列的相对关联度最高、质量最优;PCA分析结果显示产地为陕西省铜川市的黄连对主成分贡献率较高。GRA与色度测定所建立的黄连质量评价模型可作为黄连药材质量评价的参考依据。  相似文献   
39.
山药为薯蓣科植物薯蓣的根茎,其中的多糖、多酚、皂苷、黏蛋白和维生素C等成分使山药具有抗肿瘤、抗氧化、抗炎症、降血糖和降血脂等作用。不同产地的山药由于生长条件存在差异,致使药用成分含量显著不同,结合独特的炮制工艺,进而导致市场价格差别大,所以山药饮片的产地识别至关重要。为对山药饮片进行产地溯源,本文基于激光诱导击穿光谱(LIBS)技术提出多元散射矫正-改进遗传算法-支持向量机(MSC-IGA-SVM)模型对山药产地进行精确识别。使用八个不同产地的山药饮片进行LIBS实验,八种产地的山药饮片磨粉过筛后制成粉末压片,通过采集山药饮片的LIBS光谱,分别使用单一分类器与使用光谱预处理、特征提取及模式识别算法的模型对光谱的识别结果进行对比。将光谱信号按2∶1的比例划分为训练集和测试集,使用5次交叉验证K-邻近算法(KNN)模型的测试集准确率作为预处理参数优化的评价指标。各类药材的平均光谱整体趋势一致,所含谱峰基本相同,但因产地不同导致峰值强度各不相同,道地山药对一些金属元素(K, Na, Ca, Mg, Al)的富集能力大于非道地产区山药,其中,K元素特征谱线(769.90 nm)的峰值最高,即...  相似文献   
40.
A gas chromatography/mass spectrometry (GC/MS) method was developed to study the pharmacokinetics of ligustilide following oral administration to rats. The method was used for the analysis of samples taken from rats. Biological samples were prepared by liquid-liquid extraction (LLE) using an n-hexane-ether (2:1) solvent mixture for a sample clean-up step and analyzed by GC/MS with a quadrupole MS detector in selected ion monitoring mode (m/z 190). The calibration curves were linear over the concentration range 0.172-8.60 microg/mL (r > 0.99) for blood samples and a different range (r > 0.99) for different tissue samples. The limit of detection (LOD) was 1.0 ng/mL or 1.0 ng/g (three times the signal-noise ratio). Within- and between-day precision expressed as the relative standard deviation (RSD) for the method was 1.58-3.88 and 2.99-4.91%, respectively. The recovery for all samples was >80%, except for liver samples (>70%). The main pharmacokinetic parameters obtained were: T(max) = 0.65 +/- 0.07 h, C(max) = 1.5 +/- 0.2 microg/mL, AUC = 34 +/- 6 h microg/mL and K(a) = 3.5 +/- 0.6/h. The experimental results showed that ligustilide was easily absorbed, but its elimination was slow, from 3 to 12 h after oral administration. The concentrations of ligustilide in rat cerebellum, cerebrum, spleen and kidney were higher than those in other organs.  相似文献   
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