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11.
彝药金沙青叶胆的傅里叶变换红外光谱研究   总被引:4,自引:4,他引:0  
金沙青叶胆是常用彝药之一,具有独特而显著的药用价值。本文采用傅里叶变换红外光谱方法(FTIR)对金沙青叶胆的根、茎、花不同部位进行了分析研究。研究表明,其根、茎、花的红外光谱有较大的相似性,主要吸收峰位置基本相同,它们共同显示出该药材独特的红外指纹特征,三者所含主要物质成分基本相同,由此说明在彝医临床应用中将该药全草入药具有其合理性,但其根、茎、花的红外光谱的吸收峰位置、个数、强度、峰形又有一些差异,表明其不同部位所含的化学成分及其相对含量存在一定的差异。本文的分析研究为临床应用及开发利用该彝药提供了科学依据。  相似文献   
12.
采用傅里叶变换红外光谱法(Fourier transform infrared spectroscopy,FTIR)、偏最小二乘判别分析(partial least square discriminant analysis,PLS-DA)和系统聚类分析(hierarchical cluster analysis,HCA)快速鉴别不同产地川东獐牙菜(Swertia davidi Franch)。采集4个不同地区70株样品不同部位的红外光谱数据,原始光谱数据经预处理(自动基线校正,自动平滑,一阶求导,二阶求导)后导入OMNIC 8.2,比较吸收峰的差异;用SIMCA-Pa+10.0进行偏最小二乘判别分析(PLS-DA),以前三个主成分三维得分图比较产地鉴别效果;红外光谱数据导入SPSS 19.0,进行系统聚类分析(HCA),通过树状图比较不同部位分类效果。结果显示,(1)不同产地根的光谱图在1 739,1 647,1 614,1 503,1 271,1 243,1 072cm~(-1)附近的吸收峰有差异,不同产地茎的光谱图在1 503,1 270,1 246cm~(-1)吸收峰附近有差异;(2)相同产地不同部位的光谱特征峰有差异;(3)PLS-DA分析结果显示自动基线校正+自动平滑+二阶求导这种预处理方式分类效果最好,根的红外光谱数据产地鉴别效果最佳;(4)HCA的树状图,显示根的聚类分析结果正确率83%,茎的聚类分析结果正确率49%,叶的聚类分析结果正确率70%。FTIR技术结合PLS-DA与HCA方法能够快速准确地鉴别不同产地川东獐牙菜,不同部位产地鉴别效果有差异,根的光谱数据产地鉴别效果最佳,二阶求导处理增强了样品的特异性,使PLS-DA的三维主成分得分图分类效果更明显。  相似文献   
13.
Fourteen monohydroxy‐substituted polyunsaturated fatty acids, including two new compounds, (9Z,12S,13E,15Z)‐12‐hydroxyoctadeca‐9,13,15‐trienoic acid ( 10 ) and (9Z,12Z,14E,16R)‐16‐hydroxyoctadeca‐9,12,14‐trienoic acid ( 13 ), and 12 known ones, i.e., 1 – 9, 11, 12 , and 14 , were isolated from the whole plants of Swertia japonica Makino , and characterized as the corresponding methyl esters 1a – 14a . Their structures were elucidated by analysis of the corresponding spectroscopic data, and the absolute configurations of 10a and 13a were determined by the Mosher‐ester method. The CD spectra (Table) of compounds 1a – 14a are briefly discussed. This is the first report on the isolation of monohydroxy‐substituted polyunsaturated fatty acids from the Swertia genus in Gentianaceae.  相似文献   
14.
野生与种植青海川西獐牙菜中矿物质元素含量特征   总被引:1,自引:2,他引:1  
青海地道中藏药材川西獐牙菜人工种植试验初见成效。为了对比野生与种植青海川西獐牙菜中矿物质元素的变化,分别采集野生与种植青海川西獐牙菜种子采收前后的全植株,采用原子吸收光谱仪分析测定了其钾、钠、钙、镁等矿物质元素含量。结果表明,野生川西獐牙菜中,青海玉树较四川川西地区的钠、磷元素含量高,钙、钾、镁元素含量低。种植青海川西獐牙菜在成熟种子采收后较采收前钠、镁、钙、磷等显著增加,且种植青海川西獐牙菜与青海玉树地区野生川西獐牙菜中矿物质元素含量较为接近。  相似文献   
15.
The plant Swerlia punicea Hemsl. (Gentianaceae), distributed in Southwest China, isused in Chinese medicine for acute bilious hepatitis and cholecystitis'. Previousinvestigations of this plant have led the isolation of various compounds'. In thisinvestigation, seven compounds were isolated tyom the whole plants of S. punicea,collected in E-Shan, Yunnan Province in July, 1997 and identified by P. Y. Bet inKunming institUte of Botany, Chinese Academy of Sciences, where the specimen isdep…  相似文献   
16.
Swertia chirayita is one of the potential medicinal plants of the family Gentianaceae in traditional medicine. Due to its high demand and scarcity, trade of chirayita is affected by adulterants. Swertia species from Western Ghats were compared with S. chirayita for phytochemical characterisation and antioxidant activities by using different extracts. This study revealed that acetone is the best extraction solvent of phenolic and flavonoid compounds with antioxidant properties as compared with other extracts. S. chirayita showed better antioxidant activity than other species with highest content of phenolics and flavonoids. Among the species from Western Ghats, Swertia minor has better antioxidant properties with higher content of phenolics and flavonoids when compared with S. chirayita. Gallic acid was detected in all species under study by using HPLC analysis. The Swertia species under study showed similar phytochemical properties and antioxidant potential and hence their use as substitute to S. chirayita needs to be further investigated.  相似文献   
17.
Swertia chirayita is an endangered medicinal herb widely used as an antidiabetic. It contains two major classes of metabolites, secoiridoids and xanthones, i.e. swertiamarin, mangiferin, amarogentin and amaroswerin. The biosynthetic pathways for these chemical constituents are not completely deciphered due to gaps and redundancy of routes proposed such as for mangiferin. The missing intermediates in pathways were detected through LC-ESI-QToF-HRMS/MS, including the detection of new secoiridoids, amaronitidin and gentiopicroside. The study also reports that the biosynthesis of amaronitidin occurs through the coupling of gentiopicroside and biphenyl acid derivatives such as amarogentin and amaroswerin. This study reports for the first time complete biosynthetic pathways for gentiopicroside, mangiferin, amarogentin, amaroswerin and amaronitidin in S. chirayita with the detection of intermediate metabolites iriflophenone, maclurin, deoxyloganic acid, loganic acid and 1,3,6,7-tetrahydroxy-9H-xanthen-9-one.  相似文献   
18.
Isolation and Crystal Structure of Xanthones from Swertia Chirayita   总被引:1,自引:0,他引:1  
1 INTRODUCTION Swertia chirayita (Buch.-Ham.) grows abundantly in the temperate regions of Himalayas. It is used in Tibetan folk medicine as the traditional remedy for chronic fever, anaemia, asthma, liver disorders, hepatitis and stomachic. Recently, th…  相似文献   
19.
为对比野生与施肥(尿素和磷酸二铵)种植青海川西獐牙菜中元素含量的变化,分别采集野生和6~10月施肥种植川西獐牙菜全植株,采用原子吸收光谱仪分析测定了其钾、钠、钙、镁等矿物质元素含量和铜、锌、铁、锰、钴等微量元素含量。结果表明,施肥种植川西獐牙菜中矿物质元素、微量元素含量除钾外,均高于野生种,并在9~10月份达到最高水平,可替代野生种人药,按需适时采收,以解决资源匮乏。  相似文献   
20.
雷宇佳  高明哲  王莉  肖红斌 《色谱》2010,28(9):902-904
龙胆苦苷(GPS)是龙胆类药材及其相关制品质量控制的指标成分。本研究利用制备型高效液相色谱从川西獐牙菜提取物中分离纯化龙胆苦苷对照品。对制备色谱的流动相组成、流速、进样量和检测波长等制备参数进行了优化。采用的色谱柱为C18柱(200 mm×50 mm, 5 μm),流动相为甲醇和0.1%乙酸水溶液(体积比为30:70),流速为75 mL/min,检测波长为254 nm,进样体积为500 μL。在30 min的运行时间内,龙胆苦苷与其他干扰成分得到了很好的分离,产品纯度达到了99%以上。此方法具有快速高效、产品纯度高的特点,可用于制备龙胆苦苷对照品和对龙胆苦苷制品的质量控制。  相似文献   
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