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1.
Mancek B  Kreft S 《Talanta》2005,66(5):1094-1097
Purple coneflower (Echinacea purpurea) is an immunostimulating drug, containing multiple substances. The most important in activity are polysaccharides, caffeic acid derivatives (cichoric acid), alkamides and glycoproteins. It is not clear yet, which substances are responsible for activity. Cichoric acid is an appropriate marker of the quality of E. purpurea containing product, because it has immune stimulatory effects and it is susceptible to degradation.

In this work, an improved capillary electrophoresis method for determining cichoric acid in dried press juice from purple coneflower was developed. The optimal conditions were: electrophoretic buffer—75 mM borate, pH 8.8; injection 20 mbar for 20 s; separation at 20 kV; detection at 350 nm, temperature 35 °C.  相似文献   


2.
A rapid and sensitive assay based on ultra‐high performance liquid chromatography with electrospray ionization tandem mass spectrometry was established and validated for the simultaneous determination of cichoric acid, chlorogenic acid, quinic acid, and caffeic acid in rat plasma after oral administration of Echinacea purpurea extract using butylparaben as the internal standard. Samples were pretreated by liquid–liquid extraction with ethyl acetate. The separations for analytes were performed on an ACQUITY UPLC HSS C18 column (1.8 μm 2.1 × 100 mm) using a gradient elution program with acetonitrile/10 mM ammonium acetate (pH 5.6) at a flow rate of 0.3 mL/min. The analytes were detected in multiple reaction monitoring mode with negative electrospray ionization. The lower limit of quantification of each analyte was not higher than 10.85 ng/mL. The relative standard deviation of the intraday and interday precisions was less than 14.69%. The relative errors of accuracies were in the range of –13.80 to 14.91%. The mean recoveries for extraction recovery and matrix effect were higher than 80.79 and 89.98%, respectively. The method validation results demonstrated that the proposed method was sensitive, specific, and reliable, which was successfully applied to the pharmacokinetic study of four components after oral administration of Echinacea purpurea extract.  相似文献   

3.
应用气相色谱-质谱法测定了地板中甲苯、乙苯、邻二甲苯、间二甲苯、对二甲苯、苯乙烯、乙酸丁酯、正十一烷等8种挥发性有机物质的含量。地板样品(5g)用甲醇(15mL)超声提取20min,所得提取液用Rxi-5ms毛细管色谱柱分离,在选择离子监测模式下测定。8种挥发性有机物质的质量浓度(间二甲苯与对二甲苯合并计算)均在0.5~10.0mg·L-1范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.05~1.0mg·L-1之间。加标回收率在98.0%~105%之间,测定值的相对标准偏差(n=5)在2.3%~6.6%之间。  相似文献   

4.
Echinacea purpurea (EP) is a common medicinal material for extracting anti-RSV components. However, up to now, there has been no effective and simple method to comprehensively reflect the quality of EP. In our current study, the quality of Echinacea purpurea (L.) Moench samples from six different cultivation locations in China was evaluated by establishing a high-performance liquid chromatography (HPLC) fingerprint, combining chemical pattern recognition and multi-component determination. In this study, the chemical fingerprints of 15 common peaks were obtained using the similarity evaluation system of the chromatographic fingerprints of traditional Chinese medicine (2012A Edition). Among the 15 components, three phenolic acids (caftaric acid, chlorogenic acid and cichoric acid) were identified and determined. The similarity of fingerprints of 16 batches of Echinacea purpurea (L.) Moench samples ranged from 0.905 to 0.998. The similarity between fingerprints of five batches of commercially available Echinacea pupurea (L.) Moench and the standard fingerprint ”R” ranged from 0.980 to 0.997, which proved the successful establishment of the fingerprint. PCA and HCA were performed with the relative peak areas of 15 common peaks (peak 3 as the reference peak) as variables. Anhui and Shaanxi can be successfully distinguished from the other four cultivation areas. In addition, the index components of caftaric acid, chlorogenic acid and cichoric acid were in the range of 1.77–8.60 mg/g, 0.02–0.20 mg/g and 2.27–15.87 mg/g. The results of multi-component index content determination show that the contents of the Shandong cultivation area were higher, followed by Gansu, Henan and Hebei, and the lowest were Anhui and Shaanxi. The results are consistent with PCA and HCA, which proved that the quality of Echinacea purpurea (L.) Moench from different origins was different. HPLC fingerprint combined with chemical pattern recognition and multi-component content determination was a reliable, comprehensive and prospective method for evaluating the quality of Echinacea purpurea (L.) Moench. This method provides a scientific basis for the quality control and evaluation of Echinacea purpurea (L.) Moench.  相似文献   

5.
HPLC法同时测定松果菊属中4种酚类化合物   总被引:4,自引:0,他引:4  
松果菊属(Echinacea Moenck.)是原产于美洲的一类菊科野生花卉,也称“紫锥菊”。该属植物共有8种及数个变种,均为多年生草本,其中已开发为药品者主要为淡紫松果菊(E.palli-a)、狭叶松果菊(E.angustifolia)及紫花松果菊(E.purpurea)[1]。松果菊属植物主要用于促进机体的免疫功能  相似文献   

6.
《Electroanalysis》2017,29(4):1131-1140
A simple and rapid electrochemical method was established to quantify the total polyphenol (TP) content and assess their antioxidant activity (AA) in roots of three Echinacea purpurea (E. purpurea ) species using square wave voltammetry (SWV). Individual polyphenol components were identified, and then quantified by ultra‐high performance liquid chromatography coupled with mass spectrometery (UPLC‐MS). Two major polyphenols, chicoric (ChA) and caftaric (CFT) acids, were identified by mass spectroscopy in the extract of E. purpurea samples. The Accuracy of the proposed SWV electrochemical method for TP content and AA analysis was validated by the highly sensitive UPLC‐MS technique and standard ABTS method, respectively. A high correlation was noticed between the results, indicating the high sensitivity and reliability of the proposed SWV method for polyphenols analysis and AA evaluation in natural herbal samples.  相似文献   

7.
A series of ubiquitously occurring saturated and monounsaturated six-carbon aldehydes, alcohols and esters thereof is summarised as ‘green leaf volatiles’ (GLVs). The present study gives a comprehensive data collection of retention indices of 35 GLVs on commonly used non-polar DB-5, mid-polar DB-1701, and polar DB-Wax stationary phases. Seventeen commercially not available compounds were synthesised. Thus, the present study allows reliable identification of most known GLV in natural plant volatile samples. Applications revealed the presence of several seldom reported GLVs in headspace samples of mechanically damaged plant leaves of Carpinus betulus and Fagus sylvatica.  相似文献   

8.
赵迪  沈铮  闫晓辉  吴大朋  丁坤  关亚风 《分析化学》2013,41(8):1153-1158
基于多孔膜萃取水中挥发性有机物和微捕集技术,构建了一套水中挥发性有机物(Volatile OrganicCompounds,VOCs)样品前处理装置,可自动、在线、连续完成水中挥发性有机物萃取、富集、热解析,传输给气相色谱分离检测。实验分别对膜萃取材料、萃取温度、萃取时间、吹扫气流速等进行了系统优化,并用于氯仿、1,2-二氯甲烷、四氯化碳、三氯乙烯、甲苯、四氯乙烯、乙苯、氯苯、苯乙烯9种挥发性有机物的检测。研究结果表明,采用膜萃取/微捕集装置,与气相色谱联用,在萃取温度60℃,萃取时间30 min,吹扫气流速8 mL/min条件下,采用氢焰离子化检测器(Flame ionization detector,FID),对氯代烃的检出限达到0.003~0.041μg/L,精确度为2.7%~13.0%,线性相关系数均大于0.9936,适用于在线检测水中挥发性有机物。  相似文献   

9.
土壤中挥发性有机化合物的GC-MS测定   总被引:12,自引:0,他引:12  
利用气相色谱-质谱联用技术,对某废弃化工厂原厂区及附近农田的土壤中可能存在的60种挥发性有机化合物进行了定性和定量分析;采用质量保证和质量控制步骤对分析结果进行监测,结果令人满意。  相似文献   

10.
提出了热脱附-气相色谱-质谱法测定空气中54种挥发性有机物含量的方法。用HP-INNOWAX毛细管色谱柱分离,电子轰击离子源全扫描和选择离子检测模式检测。54种挥发性有机物的方法检出限在0.11~0.28μg.m-3之间。回收率在85%~107%之间,相对标准偏差(n=7)小于15%。  相似文献   

11.
Abstract

The high volatility and low water solubility of volatile organic compounds (VOCs), make the collection of representative samples difficult. The standard grab sampling method only gives information of that moment in time when the sample is taken. When the composition of VOCs is varying, continuous composite sampling will give a more representative sample. However, no thorough evaluation of its use for VOCs has been reported.

The use of an automatic continuous composite sampler for the analysis of VOCs in water was studied. The causes and magnitude of the VOCs losses during the sampling process were determined.

Adsorbent cartridges were used to trap the VOCs escaping from solution during the sampling process. Sorption phenomena occurring on the containers and/or tubings were also evaluated. Sorption losses were much more significant than volatilization losses.

The results indicate that a modified version of this sampler can be an alternative for the long term sampling of water for VOC analysis.  相似文献   

12.
建立了高速逆流色谱(HSCCC)分离制备紫锥菊花色苷类化合物的方法,并对所获得的2个花色苷单体进行了体外抗氧化性实验。以新鲜紫锥菊花瓣为原料,含0.1%HCl的60%乙醇为溶剂避光冷浸提取,经乙酸乙酯萃取和D101大孔吸附树脂(100 mL,2 cm×30 cm)纯化后,得2.1 g紫锥菊花色苷提取物干粉样品。以水-正丁醇-甲基叔丁基甲醚-乙腈-三氟乙酸(6∶3∶2∶1∶0.001)为HSCCC分离溶剂系统,上相为固定相,下相为流动相,流速2.0 mL/min,进样量160 mg,通过一次分离得到2种花色苷单体化合物,经HPLC检测其纯度分别达95.1%(9.8 mg)、98.2%(14.3 mg),MS及NMR技术鉴定其结构分别为矢车菊素-3-O-β-D葡萄糖苷(化合物1)和矢车菊素-3-O-(6″-O-丙二酰-β-D葡萄糖苷)(化合物2)。以Vc为对照组,对所获得的2种花色苷单体化合物进行了1,1-二苯基-2苦肼基(DPPH.)体外抗氧化性能评价,结果显示2种花色苷对DPPH.的半清除率(EC50)均小于10 mg/L,小于对照样Vc,表明2种花色苷均具有较强的自由基清除作用,且化合物1的清除能力强于化合物2。  相似文献   

13.
提出了顶空固相微萃取-气相色谱-质谱法测定食用植物油中35种挥发性有机物(VOC′s)含量的方法。为使固相微萃取达到更高的效率,选用75μm碳分子筛-聚二甲基硅氧烷纤维作为微萃取的涂层,萃取温度及时间为90℃和30 min。用DB-5MS毛细管色谱柱分离,电子轰击离子源全扫描监测模式检测。35种VOC′s在一定的质量浓度范围内与其峰面积呈线性关系,方法的检出限(3S/N)在0.03~6.84μg·L-1之间。在3个添加水平上做回收试验,加标回收率在91.0%~108.3%之间,相对标准偏差(n=5)小于10%。  相似文献   

14.
采用热脱附与稳定同位素质谱联用技术分析了城市不同源及大气环境中挥发性有机物排放的单体同位素特征。系统考察了样品进样量、进样方式和样品分离度对同位素分馏影响情况。使用填有Tenax TA的吸附管采集汽油车尾气、汽油挥发、柴油车尾气、柴油挥发、溶剂挥发和餐饮油烟等污染源,以及城市不同功能区的挥发性有机物(VOCs)样品,不同污染源中挥发性有机物的稳定碳同位素δ13C值不同,97#汽油车尾气的δ13 C值偏重,平均值为-25.84‰,富集13 C;餐饮油烟的δ13 C值偏轻,平均值为-30.26‰。油品挥发比燃烧后以尾气的形式排放的苯系物δ13 C值重。厦门市各功能区挥发性有机物的δ13 C平均范围在-27.03‰~-25.40‰,接近于汽油和柴油挥发及尾气中的δ13 C值,表明厦门市空气中挥发性有机物以机动车排放源为主。  相似文献   

15.
研究了富勒烯烟炱对挥发性有机物(VOCs)的吸附作用.17种VOCs气体在烟炱上的比保留体积Vg20为17.4~2634L/g.富勒烯烟炱充填的吸附管对VOCs气体的吸附-热脱附回收率在40.8%~117%之间,大部分为(100±20)%.结果表明,富勒烯烟炱能够用于吸收和富集大气中痕量的VOCs  相似文献   

16.
应用吹扫捕集-气相色谱-质谱法测定土壤中27种挥发性有机物的含量。选定在25℃条件下吹扫捕集11min,取样品溶液5mL于吹扫瓶中,利用Tekmar Stratum吹扫捕集器直接进样,经TR-5MS毛细管色谱柱分离,电子轰击电离(EI)全扫描和选择离子扫描检测,内标法进行定量测定。27种挥发性有机物的质量浓度与其峰面积在一定的浓度范围内呈线性关系,方法检出限(3S/N)在0.077~0.69μg·kg~(-1)之间。样品加标平均回收率在86.5%~117.5%之间,相对标准偏差(n=7)在1.6%~8.2%之间。  相似文献   

17.
Summary Volatile organic compounds (VOC) are present in indoor air at concentrations generally higher than in outdoor air. In this study VOC concentrations in the air of two classrooms differing in insulation, and in the expired air of children in them, were investigated. Qualitative and quantitative determinations were done by gas chromatography-mass spectrometry techniques. Differences in the concentrations of VOC in indoor air and in the expired air of the children were linked to the endogeneous or exogeneous origin of the compounds, to the activities of the children and to the quality of indoor-outdoor air exchanges.  相似文献   

18.
Cichoric acid and caftaric acid are the main phenolic compounds in Echinacea purpurea tops. The level of these phenolic compounds in E. purpurea extracts is affected by different factors such as seasonal variations, drying methods, extraction methods, and growing location of the plant. HPLC analysis of caffeic acid derivatives in extracts of Echinacea purpurea (Cultivar) aerial parts, produced by boiling water extraction and ethanol-water extraction methods, showed various levels of the derivatives. Our findings revealed that the Iranian cultivated E. purpurea had a high level of cichoric acid (3.5–5.7 %). Caftaric acid was also the main phenolic compound in E. purpurea tops (3.1–4.5 %). After 2 h of boiling water extraction, the level of cichoric acid was 5.7 %, whereas the level of this acid in 60:40 ethanol-water extraction did not exceed 3.9 %. Published in Khimiya Prirodnykh Soedinenii, No. 2, pp. 150–152, March–April, 2008.  相似文献   

19.
催化燃烧是目前最有效的处理挥发性有机物(VOCs)技术之一. 本文从催化剂活性组分、催化剂载体、有效组分颗粒大小、水蒸汽的影响及催化燃烧反应中的积碳等几个方面, 对近年来催化燃烧处理VOCs的研究进行了总结. 分析表明: 贵金属催化剂的研究主要着重于选择有效的载体和双组分贵金属催化剂; 非贵金属催化剂的研究主要集中在高活性的过渡金属复合氧化物、钙钛矿和尖晶石型等催化剂的研制, 还有这些活性组分粒径大小及载体对催化燃烧VOCs反应活性的影响;此外, 在实际应用中,水蒸汽和催化剂积碳失活等问题对催化燃烧VOCs的反应也有很大影响. 本文的评述将为选择合适的催化燃烧技术处理VOCs污染物提供一定参考.  相似文献   

20.
催化燃烧是目前最有效的处理挥发性有机物(VOCs)技术之一. 本文从催化剂活性组分、催化剂载体、有效组分颗粒大小、水蒸汽的影响及催化燃烧反应中的积碳等几个方面, 对近年来催化燃烧处理VOCs的研究进行了总结. 分析表明: 贵金属催化剂的研究主要着重于选择有效的载体和双组分贵金属催化剂; 非贵金属催化剂的研究主要集中在高活性的过渡金属复合氧化物、钙钛矿和尖晶石型等催化剂的研制, 还有这些活性组分粒径大小及载体对催化燃烧VOCs反应活性的影响;此外, 在实际应用中,水蒸汽和催化剂积碳失活等问题对催化燃烧VOCs的反应也有很大影响. 本文的评述将为选择合适的催化燃烧技术处理VOCs污染物提供一定参考.  相似文献   

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