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1.
Angelica pubescens and Angelica sinensis belong to the Umbelliferae family and both are used as traditional Chinese medicines. In the present study, headspace solid-phase microextraction (HS-SPME) with gas chromatography-mass spectrometry (GC-MS) was used for the analysis of the volatile constituents present in their roots. Eighty-seven compounds in Angelica pubescens and thirty-six compounds in Angelica sinensis were identified by GC-MS. Their relative contents were calculated by the peak area ratio. HS-SPME was compared to steam distillation (SD) by analyzing the volatile constituents of Angelica sinensis root. A good agreement between results obtained with both techniques was found. As a conclusion, HS-SPME is a powerful tool for determining the volatile constituents present in the TCMs.  相似文献   
2.
A simple and specific high‐performance liquid chromatographic method has been developed and validated to simultaneously determine seven secoiridoid glucosides for the first time. Three of them were separated from the ethanolic extract of the roots of Ilex pubescens for the first time, namely nuezhenide A, ligusides B and oleonuezhenide. In quantitative analysis, all of the calibration curves showed good linear regression (r > 0.999) within the tested ranges, and the mean recoveries of three different concentrations ranged from 97.6 to 101.2%. The limit of detection and limit of quantification were <4.18 and 11.63 ng mL−1, respectively. The relative standard deviation for repeatability and the precision of seven analytes were <3.4 and 1.9%, respectively. The established method was successfully applied to simultaneous determination of seven secoiridoid glucosides in 11 batches of samples collected from different habitats in China.  相似文献   
3.
目的研究毛冬青总皂苷对脑缺血再灌注损伤的保护作用,并初步探讨其血液微量元素的影响。方法动物随机分为假手术组、模型组、毛冬青总皂苷(高、中、低)剂量组及阳性药物对照组,运用大鼠大脑中动脉栓塞,制作脑缺血再灌注损伤模型,缺血10 min后,给药组及阳性药物组于舌下静脉给予高、中、低剂量的毛冬青总皂苷及假手术组、模型组给予等体积的溶剂。缺血60 min再灌注24 h后,每组取8只大鼠断头取脑,TTC染色,测定脑梗死体积;取血,测定血液中3种微量元素Ca、Zn、Cu的含量。结果毛冬青总皂苷组与模型组相比,毛冬青总皂苷治疗组脑梗死体积减小,病理变化较轻;模型组与假手术组比较血液中Ca、Cu含量增加明显有统计学意义,Zn含量明显降低与假手术组比较有统计学意义(P0.05),毛冬青高、中、低剂量组与模型组比较Ca、Cu含量明显降低,Zn含量明显升高,而且呈明显的量效关系,与模型组比较有统计学意义(P0.05)。结论毛冬青总皂苷对脑缺血再灌注损伤具有一定的保护作用,其保护机制与毛冬青总皂苷抗氧化作用及增强氧自由基的清除有关。  相似文献   
4.
5.
The phytochemical investigation of the aerial parts of Siegesbeckia pubescens L. yielded 16 sesquiterpenoids, including a novel 11(7→6)abeo‐14‐norcarabrane sesquiterpenoid, pubescone ( 1 ), and a new germacrane sesquiterpene, 5 . The molecular structures of the isolated compounds were elucidated on the basis of extensive spectroscopic analysis, including 1D‐ and 2D‐NMR.  相似文献   
6.
Three new neolignans, (7S,8S,7′E)‐4,9‐dihydroxy‐3,7,3′,9′‐tetramethoxy‐8,4′‐oxyneolign‐7′‐ene ( 1 ), (7R,8S,7′E)‐4, 9‐dihydroxy‐3,7,3′,9′‐tetramethoxy‐8,4′‐oxyneolign‐7′‐ene ( 2 ), (7S,8S,7′E)‐5, 9‐dihydroxy‐3,7,3′,5′,9′‐pentamethoxy‐8,4′‐oxyneolign‐7′‐ene ( 3 ), and one new phenylpropanoid, threo‐5‐hydroxy‐3,7‐dimethoxyphenylpropane‐8,9‐diol ( 4 ), were isolated from the leaves and stems of Toona ciliata var. pubescens. Their structures were determined on the basis of spectroscopic analysis, especially 2D‐NMR, HR‐ESI‐MS, and CD data. The antiproliferative activities of these compounds against four tumor cell lines (A549, Colo 205, QGY‐7703, and LOVO) were also evaluated by MTT (=(3‐(4,5‐dimethylthiazol‐2‐yl)‐2,5‐diphenyl‐2H‐tetrazolium bromide) method.  相似文献   
7.
刚竹毒蛾虫害检测对毛竹的生长和竹业的发展起着至关重要的作用。根据高光谱冠层光谱信息与刚竹毒蛾虫害程度之间的关系,提取冠层光谱中与虫害紧密相关的特征波长、指数以及光谱参数等,利用Fisher判别分析法建立刚竹毒蛾虫害程度检测模型。分别以原始光谱的400~508,586~693和724~900 nm处的波长、包络线去除光谱的400~756 nm之间的特征波长、9种冠层光谱植被指数和7种冠层特征光谱参数作为Fisher判别函数自变量,构建判别函数。收集300组毛竹叶片虫害样本数据,随机划分为210组建模集与90组验证集,根据检测精度、Kappa系数以及判定系数R2作为检验标准,对建立的判别函数进行效果评价与对比。结果表明,以原始光谱、去包络线光谱、冠层指数、光谱参数为自变量建立的Fisher判别函数的检验精度分别为:84.4%,81.1%,79.7%,78.7%;Kappa系数分别为:0.79,0.74,0.74,0.76;R2分别为:0.89,0.88,0.88和0.85。由此可知,Fisher判别分析模型建立的函数具备很好的刚竹毒蛾虫害程度检测能力,而且基于冠层原始光谱建立的判别函数检测效果最佳。根据高光谱数据的冠层原始光谱建立的判别函数对福建省顺昌县大干镇武坊村的洋门和土垅村的上湖竹林进行刚竹毒蛾虫害程度检测。检测结果为:上湖两个样区的竹林以健康为主。洋门两个样区虫害程度以中度和重度为主。因此基于无人机高光谱遥感对于刚竹毒蛾虫害的大面积检测具有可行性,该方法可为虫害检测的探究提供参考,为基于冠层遥感虫害检测贡献理论支撑。  相似文献   
8.
橄榄苦甙的NMR数据解析   总被引:7,自引:0,他引:7  
对橄榄苦甙进行了1H和13C MNR检测, 通过DEPT和1H-1H COSY、HMQC、HMBC、NO ESY等2D NMR对其1H和13C NMR数据进行了全归属和较详细的解析, 并指出其NMR数据特征.  相似文献   
9.
对从重齿毛当归(AngelicapubescensMaximf.biserrataShanetYuan)根及根茎中分得的12种6-或8-脂代-7-氧-香豆素和8种二氢呋喃香豆素衍生物进行了1H和13CNMR分析研究.结合文献.做出规律性总结.运用2DNMR技术.对文献中当归醇类化合物碳谱中的个别错误归属给予了纠正,并首次探讨了此类化合物的MS裂解途径.  相似文献   
10.
The phytochemical investigation of an alkaloidal extract of Holarrhena pubescens roots led to the isolation and identification of a new pregnene-type alkaloid, mokluangin D (1), together with nine known steroidal alkaloids (2–10). The structure of the new metabolite was determined on the basis of spectroscopic analyses including 1D- and 2D-NMR spectroscopy and mass spectrometry. Compounds 3 and 4 showed potent antimalarial activity against Plasmodium falciparum K1 stain with IC50 values of 1.2 and 2.0 μM, respectively, and showed weak cytotoxic activity against the NCI-H187 cell line with IC50 values of 27.7 and 30.6 μM, respectively. The substituent groups at C-3 and the carbonyl group at C-18 are important for the activity against the P. falciparum K1 stain.  相似文献   
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