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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.
当归挥发性有机物的SPME/GC-MS分析   总被引:1,自引:0,他引:1  
采用不同极性的SPME萃取吸附了当归的挥发性有机物,并用GC-MS定性和相对定量,比较了不同萃取时间和不同萃取温度下所获得的挥发性有机物的差异。结果表明:藁本内酯和α-蒎烯是其主要成分。随着萃取时间的延长,α-蒎烯含量逐渐减少,藁本内酯含量逐渐升高;随着萃取温度的升高,低沸点化合物含量逐渐减少,高沸点化合物含量逐渐增加。  相似文献   
3.
将白芷药材粉碎至通过孔径为(250±9.9)μm的网筛,并称取此白芷粉末样品2.00g于聚丙烯管中与水10mL混匀,再加入含1%(体积分数)乙酸的乙腈10.0mL,涡旋1min后加入无水硫酸镁4g和乙酸钠1g,剧烈振荡3min,离心5min,取其上清液5.0mL置于已盛有无水硫酸镁900mg、N-丙基乙二胺(PSA)450mg和硅胶300mg的净化管中,剧烈振荡5min使净化完全,离心5min。移取上清液3.0mL于40℃水浴中减压蒸缩至近干。加入50μg·L^-1的磷酸三苯酯内标溶液300μL,加入乙腈定容至1.0mL,经0.20μm滤膜过滤,取其滤液,按仪器工作条件进行超高效液相色谱-串联质谱法分析。选用Eclipse Plus C18色谱柱和以不同比例的(A)含10mmol·L^-1甲酸铵的0.1%(体积分数)甲酸溶液和(B)乙腈的混合液为流动相,按梯度洗脱程序对白芷中可能残留的51种禁用农药进行色谱分离,并在电喷雾离子源正、负离子(ESI+和ESI-)电离方式和动态多反应监测(dMRM)模式条件下进行串联质谱法测定。采用基质匹配标准曲线法定量。51种农药的质量浓度在一定范围内与其对应的峰面积呈线性关系,并测得其检出限(3S/N)为0.3~5.0μg·kg^-1。标准加入法回收试验的结果显示,其中大部分农药的回收率在71%以上,测定值的相对标准偏差(n=6)均小于20%。按此方法分析了70批白芷样品,共检出16种农药,其中甲拌磷亚砜的检出率达95%,最高检出量为15.2μg·kg^-1;甲拌磷砜和毒死蜱的检出率均为10%,最高检出量依次为3.5,45.0μg·kg^-1,其余13种农药的检出率均低于5%,且检出量均较低。  相似文献   
4.
Angelica sinensis (Oliv.) Diels (Umbelliferae), known as Danggui in Chinese, one of the most important traditional Chinese medicines, is used for tonifying blood and treating female irregular menstruation and amenorrhoea. It is also used for treatment of …  相似文献   
5.
The study was carried out to determine the effects of gamma irradiation on the volatile flavor components including essential oils, of Angelica gigas Nakai. The volatile organic compounds from non- and irradiated A. gigas Nakai at doses of 1, 3, 5, 10 and 20 kGy were extracted by a simultaneous steam distillation and extraction (SDE) method and identified by GC/MS analysis. A total of 116 compounds were identified and quantified from non- and irradiated A. gigas Nakai. The major volatile compounds were identified 2,4,6-trimethyl heptane, α-pinene, camphene, α-limonene, β-eudesmol, α-murrolene and sphatulenol. Among these compounds, the amount of essential oils in non-irradiated sample were 77.13%, and the irradiated samples at doses of 1, 3, 5, 10 and 20 kGy were 84.98%, 83.70%, 83.94%, 82.84% and 82.58%, respectively. Oxygenated terpenes such as β-eudesmol, α-eudesmol, and verbenone were increased after irradiation but did not correlate with the irradiation dose. The yields of active substances such as essential oil were increased after irradiation; however, the yields of essential oils and the irradiation dose were not correlated. Thus, the profile of composition volatiles of A. gigas Nakai did not change with irradiation.  相似文献   
6.
Angelica sinensis (Danggui in Chinese), a well-known traditional Chinese medicine, is also used as a health food product for women's care in Europe and America. Therefore, the demand for Danggui is enormous throughout the world. Due to the shortage of Angelica sinensis, Angelica acutiloba and Angelica gigas are commonly used as the substitutes of Danggui in the market of southeast Asia. However, the three common Angelica roots showed variation in their genetic and chemical composition. Up to date, it is thought that ferulic acid, ligustilide and other phthalides such as butylidenephthalide are the biologically active components of Danggui. In this paper, the contents of 13 compounds including ferulic acid, Z-ligustilide, E-ligustilide, Z-butylidenephthalide, E-butylidenephthalide, 3-butylphthalide, 3-butylidene-4-hydroxyphthalide, senkyunolide A, 6,7-epoxyligustilide, senkyunolide F, senkyunolide H, senkyunolide I, and 6,7-dihydroxyligustilide were determined or estimated by using gas chromatography-mass spectrometry (GC-MS) coupled with pressurized liquid extraction (PLE). The results showed that GC-MS coupled with PLE offered a simple, rapid and high sensitive method to analysis of components in Angelica root. And the contents of investigated compounds in Angelica sinensis, Angelica acutiloba and Angelica gigas, which are used as Danggui in China, Japan and Korea, respectively, were highly variant. It is thought that interaction of multiple chemical compounds contributes to the therapeutic effects of Chinese medicines. However, the overall clinical efficacy of these different Danggui has not been determined. Therefore, comparison of chemical components and pharmacological activities of different Angelica root is helpful to elucidate the mechanism of therapeutic effects of Danggui.  相似文献   
7.
A method employing ultra‐high performance liquid chromatography–tandem mass spectrometry (UHPLC–MS/MS) for determination of eight components including ferulic acid, senkyunolide A, butylphthalide, ligustilide, butylidenephalide, senkyunolide I, senkyunolide H and levistolide A in Angelica sinensis was established. The separation was carried out using a Waters ACQUITY UHPLC BEH C18 column with gradient elution with 0.1% formic acid aqueous and acetonitrile at a flow rate of 0.4 mL/min. Good linearity was attained with R2 of 0.9983–0.9998 in wide concentration ranges. The method had limit of detection (LOD) and quantitation (LOQ) in the range of 0.42–6.98 ng/mL and 1.39–23.28 ng/mL, respectively. Intra‐ and inter‐day precisions varied with relative standard deviations (RSDs) from 0.33% to 0.88% and 0.37% to 1.04%, respectively. Moreover, the average recoveries were in a satisfactory range of 92.7%–102.1% with RSDs of less than 3.60%. Finally, the method was successfully applied to analyze 19 batches of A. sinensis samples grown in Min County, Gansu province, China, as well as that collected in other regions. The findings indicated that the established method is reliable and may thus be applied as a powerful tool for qualitative and quantitative analysis of components in A. sinensis, which has its implications in quality control of A. sinensis.  相似文献   
8.
明日叶黄酮类化合物清除羟基自由基活性研究   总被引:1,自引:0,他引:1  
为了研究明日叶黄酮类化合物对羟基自由基的清除作用,以明日叶(主要取叶片)为原料,用体积分数为65%乙醇提取明日叶总黄酮,测定其总黄酮含量.通过Fenton反应体系产生羟基自由基,利用明日叶提取液中的功能成分黄酮类化合物对羟基自由基的清除作用进行研究.结果表明:明日叶提取物总黄酮质量分数为10.18%,且黄酮类化合物对羟基自由基有较强清除效力,当提取物总黄酮浓度在0.1~1.0 mg/mL范围内,其与清除率呈正相关.明日叶中黄酮类化合物对羟基自由基有较强清除效力,作为天然抗氧化产品开发具有一定价值.  相似文献   
9.
A new discrimination method, called hit quality index (HQI)-voting, that uses the HQI for discriminant analysis has been developed. HQI indicates the degree of spectral matching between two spectra as known. In this method, a library sample yielding the highest HQI value for an unknown sample was initially searched and a group containing this sample was chosen as the group for the unknown sample. When overall spectral features of two groups are quite close to each other, many library samples with similar HQI values could be available for an unknown sample. In this situation, the simultaneous consideration of multiple votes (several library samples with close HQI values) for final decision would be more robust. In order to evaluate the discrimination performance of HQI-voting, three different near-infrared (NIR) spectroscopic datasets composed of two sample groups were used: (1) domestic and imported sesame samples, (2) domestic and imported Angelica gigas samples, and (3) diesel and light gas oil (LGO) samples. For the purpose of comparison, principal component analysis–linear discriminant analysis (PCA–LDA), partial least squares–discriminant analysis (PLS–DA) as well as k-nearest neighbor (k-NN) were also performed using the same datasets and the resulting accuracies were compared. The discrimination performances improved with the use of HQI-voting in comparison with those resulted from PCA–LDA and PLS–DA. The overall results support that HQI-voting is a comparable discrimination method to that of existing factor-based multivariate methods.  相似文献   
10.
FAAS测定酒当归中的微量元素   总被引:1,自引:0,他引:1  
采用硝酸-高氯酸(4+1)混合酸消解样品,用火焰原子吸收光谱法(FAAS)测定了酒当归中Fe、Cu、Mg、Ca、Mn、Zn、Ni、Cr、Pb 9种微量元素的含量。结果表明,9种元素的质量浓度在一定的范围内均与其峰面积呈线性关系。该法用于酒当归样品分析,9种元素测定值的相对标准偏差(n=6)均小于3%,标准加入法测得9种元素回收率在91.2%—109.7%之间。采用火焰原子吸收光谱法测定酒当归中9种微量元素稳定性好,结果准确可靠。  相似文献   
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