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21.
Genus Swertia is valued for its great medicinal potential; mainly Swertia chirayita (Roxb. ex Fleming) H. Karst. is used in traditional medicine for a wide range of diseases. Seco-iridoid glycosides like swertiamarin is referred with enormous pharmacological potentials. The aim of the study was to identify a suitable substitute to S. chirayita by quantifying seco-iridoid swertiamarin from five different Swertia species endemic to the Western Ghats. The reverse-phase high-performance liquid chromatography diode array detector analyses were performed and chromatographic separation was achieved on a Lichrospher 100, C18e (5 µm) column (250–4.6 mm). A mobile phase consisting of acetonitrile and water (25:75) was used for separation. Results indicated that the concentration of the marker compound has been found to vary largely between and within the species from different localities. The content of swertiamarin was the highest in S. chirayita compared to the other species studied herein, advocating the use of Swertia minor as an alternate source to S. chirayita.  相似文献   
22.
Two new xanthones (12), together with four known ones (36), were isolated from whole herb of Swertia elata. Their structures were elucidated by spectroscopic methods including extensive 1D- and 2D-NMR techniques. Their anti-tobacco mosaic virus (anti-TMV) activity test revealed that 16 showed weak anti-TMV activities with inhibition rate in the range of 15.2–28.8% at the concentration of 20 μM.  相似文献   
23.
Aim of this study was to identify pentacyclic triterpenoids betulinic acid (BA), oleanolic acid (OA) and ursolic acid (UA) from five Swertia species endemic to Western Ghats, which are used as substitutes as well as adulterants to Swertia chirayita. Our results indicate that the concentration of active compound vary largely among and within the species from different localities. OA was found in a higher amount in all species compared to BA and UA. From the results, it was clear that BA, OA and UA are present in the endemic species collected from Western Ghats, thus advocating the use of these species as alternate sources to S. chirayita. This in due course may release pressure of exploitation from natural resources of S. chirayita and help to bring it out from an endangered category from conservation point of view.  相似文献   
24.
利用红外光谱三级鉴定方法对藏药川西獐牙菜及其不同溶液提取物进行分析研究。选择川西獐牙菜中含量相对较高的药用成分龙胆苦苷作为不同溶液提取物的对照成分进行红外光谱和二阶导数光谱的分析;同时对不同浓度乙醇提取物进行二维相关光谱分析。结果显示,龙胆苦苷红外光谱中1 611和1 075cm-1处的两个主要特征峰强度的变化趋势,和川西獐牙菜不同溶剂提取物中龙胆苦苷含量变化趋势一致;提取溶剂极性相近时,提取物的红外光谱图相似;随着提取溶液极性的逐渐降低,提取物的红外谱图中2853,1 733,1 464,1 277和1 161cm-1等处吸收峰强度逐渐增强,提取物中酯类化合物含量逐渐增加,萜类化合物的提取率逐渐增加;红外光谱图极为相近的不同浓度乙醇提取物在二维红外光谱图中有很明显的差异。龙胆苦苷特征峰强度的变化趋势和不同提取物中龙胆苦苷含量变化趋势的一致性说明红外光谱分析结果能体现分析对象中所含有成分的含量变化;川西獐牙菜原药材,水提物和不同浓度乙醇提取物谱图的相似性和相似度的变化规律,说明传统用药水煎液和低浓度醇提物的科学性;红外光谱技术可成为川西獐牙菜不同提取物后期药理活性成分宏观控制,和多以复方入药的藏药研究中准确、快速、有效的分析方法。  相似文献   
25.
建立了高速逆流色谱分离川西獐牙菜中3种(口山)酮苷元的方法.溶剂系统为V(正己烷):V(乙酸乙酯):V(甲醇):V(水)=5:5:6:4,上相为固定相,下相为流动相,转速为850 r/min,流速为2.5 mL/min,温度为25℃.从川西獐牙菜氯仿萃取部位的(口山)酮苷元混合物中制备得到18mg 1,8-二羟基-3,...  相似文献   
26.
Swerilactones H–K ( 1 – 4 ), which are four novel lactones with an unprecedented C29 skeleton, were isolated from Swertia mileensis (Qing‐Ye‐Dan), an endemic Chinese herb used for treating viral hepatitis. Their structures were determined by extensive spectroscopic and X‐ray crystallographic diffraction analyses. Swerilactones H–K exhibit potent anti‐hepatitis B virus activity against HBV DNA replication with IC50 values ranging from 1.53 to 5.34 μM . For the first time, a plausible biogenetic pathway for swerilactones H–K, together with the previously reported swerilactones A–D is proposed. From a biogenetic point of view, swerilactones A–D are ascribed as secoiridoid dimers, and swerilactones H–K as secoiridoid trimers.  相似文献   
27.
Abstract

Two new xanthone glycosides (12), together with seven known analogues (39), were isolated from whole herb of Swertia punicea. The structures of these metabolites were established on the basis of detailed spectroscopic analysis and comparison with data reported in the literature. In an in vitro test, all isolates were evaluated for their anti-inflammatory activity. The results revealed that all of them showed significant anti-inflammatory activity with IC50 values ranging from 1.237 to 3.319?mM. Compounds 3, 4, and 5 (IC50 values in the range 1.237–1.987?mM) displayed more potent anti-inflammatory activity than the positive control, indomethacin (IC50 value of 2.004?mM).  相似文献   
28.
A novel monoterpene glycoside, mileenside, was isolated from Swertia mileensis by repeated normal and reverse phase silica gel chromatography and its structure was elucidated mainly based on spectral evidence.  相似文献   
29.
From the MeOH extract of the aerial parts of Swertia mileensis, four new secoiridoid glycosides were isolated, 4′‐O‐[(E)‐caffeoyl]swertiamarin ( 1 ), 4′‐O‐[(Z)‐coumaroyl]swertiamarin ( 7 ), 6′‐O‐[(E)‐coumaroyl]swertiamarin ( 8 ), and 6′‐O‐[(Z)‐coumaroyl]swertiamarin ( 9 ), together with five known compounds. Their structures were elucidated by NMR spectroscopy and tandem mass spectrometry. Detailed HPLC/MS analyses and MS/MS fragmentation pathways are discussed for the identification of the swertiamarin‐derived (E)/(Z) isomers 6 / 7 and 8 / 9 .  相似文献   
30.
同步辐射X射线荧光法分析藏药材和藏药制剂中金属元素   总被引:1,自引:0,他引:1  
同步辐射X射线荧光(SR-XRF)技术具有光强高、能量范围宽、信噪比高、检测限低、无损伤分析等特点,在元素分析中具有极为显著的优势。采用SR-XRF技术,对临床治疗肝胆疾病常用的藏药材(川西獐牙菜)及藏药制剂中的金属元素进行较为准确的定量半定量分析,以期揭示藏药中这些金属元素与其药效的关系。SR-XRF分析结果发现,藏药材川西獐牙菜中含有钾(K)、钙(Ca)、钛(Ti)、钒(V)、铬(Cr)、锰(Mn)、铁(Fe)、锌(Zn)、铅(Pb)共九种金属元素(含量均处于ppb或亚ppm级别),且不同来源样品间的元素组成具有明显的差异性。另外,发现研究的藏药复方制剂含有钾(K)、钙(Ca)、钛(Ti)、钒(V)、铬(Cr)、锰(Mn)、铁(Fe)、镍(Ni)、铜(Cu)、锌(Zn)、铷(Rb)、铅(Pb)、汞(Hg)、钴(Co)、镓(Ga)15种金属元素及一种非金属元素砷(As),各元素含量均在ppb至ppm级别,不同复方制剂中的元素组成具有显著性的差异。利用SR-XRF技术对常用藏药材和藏药制剂中元素进行了,初步揭示了传统藏药中微量金属元素与其生物学效应的关系,并发现该技术可用于藏药微量金属元素的直接、快速检测。  相似文献   
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