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121.
《Analytical letters》2012,45(12):1695-1712
This study established a new, rapid, and accurate method for bioactive compound screening by the combination of serum pharmacochemistry and serum pharmacology based on a spectrum-effect relationship model. HPLC/ESI-Q-TOF-MS was used for the chemical profiling of samples of dosed plasma, control plasma, and Radix Aconiti Lateralis decoction. A comparison was made of the resulting chemical profiles, which totaled 20 compounds including 16 prototype compounds and 4 metabolites derived from SF decoction that were detected as potential bioactive components. Using MS/MS analysis and accurate molecular weight assessments of TOF, 17 components in 20 potential bioactive compounds were structurally identified. Moreover, the pretreated plasma samples were injected into venous sinus of isolated toad hearts to investigate the cardio-toxicity according to heart ratio (HR) situation and electrocardiograph (ECG) parameters, including PR interval, QRS interval, and QT interval. Finally, 4 compounds in these 20 potential bioactive components that had closest correlation with 4 cardio-toxic experimental indexes respectively were investigated by spectrum-effect relationship model for the first time. The 4 compounds were considered as the real cardio-toxic components. This study proposed a series of potential bioactive components in Radix Aconiti Lateralis and provided a general research pattern to identify the potential bioactivity compounds in Chinese herbs or natural pharmacy.  相似文献   
122.
郭鹤男  杨学东  刘军  郑文凤 《色谱》2012,30(7):690-695
在高效液相色谱-质谱分析指导下,针对性地分离制备了黄芩药材中系列黄酮成分对照品。首先对黄芩药材乙醇提取物进行液相色谱-质谱分析,获得各色谱峰的保留时间、紫外光谱和质谱特征。经波谱数据解析结合文献对比,鉴定了黄芩药材中的19种黄酮类成分。然后根据液相色谱-质谱分析结果和文献,设计了目标成分对照品的制备流程,采用低压制备柱色谱法依次制备了黄芩苷、汉黄芩苷、黄芩素、汉黄芩素和千层纸素A共5种黄酮类成分的对照品。结果表明这5种黄酮类成分对照品的纯度均大于98%。该方法可用于针对性地快速分离制备中药中的化学成分。  相似文献   
123.
使用流动注射-氢化物发生-电感耦合等离子体原子发射光谱联用技术同时测定中药板蓝根中微量有害元素砷、铅、镉和汞的含量。对影响分析信号的主要工作条件进行了选择和优化。砷、铅、镉和汞的检出限分别为0.51、1.5、0.33和0.25μg/L;其回收率分别为98%、101%、103%和108%。本法用于中药板蓝根中微量有害元素的分析,结果满意。  相似文献   
124.
Xu S  Yang L  Tian R  Wang Z  Liu Z  Xie P  Feng Q 《Journal of chromatography. A》2009,1216(11):2163-2168
There are two species under the monograph of Radix Paeoniae Rubrae ("Chi-shao" in Chinese) in Chinese Pharmacopoeia 2005 edition-Paeonia lactiflora Pallas and Paeonia veitchii Lynch. Due to different species and growing conditions, there are significant chemical differences between the two species, which may result in the improper clinical usage under the same name. Chemical pattern expressed by high performance liquid chromatographic (HPLC) fingerprint analysis can play an important role in species differentiation and quality control of Radix Paeoniae Rubra. In the present work, HPLC fingerprints of two kinds of Radix Paeoniae Rubra have been established and analysed with chemometric methods including similarity evaluation and principal component analysis. Both of the fingerprint common patterns of the two species comprise 13 characteristic peaks, nine of which were common peaks of the two species. However, significant differences between the roots of P. veitchii and P. lactiflora exist not only in the content of certain constituents, especially phenolic acids but also in peak-to-peak ratios expressed by the fingerprint patterns. According to the recent pharmacological studies on polyphenolic constituents, root originating from P. veitchii may possess better efficacy and quality than that from P. lactiflora. Our research reveals that further pharmacological investigation is very necessary to determine whether the two species should be embodied under the same monograph in Chinese Pharmacopoeia.  相似文献   
125.
Yi L  Liang Y  Wu H  Yuan D 《Journal of chromatography. A》2009,1216(11):1991-2001
Radix Angelicae Sinensis, known as Danggui in China, is one of the most popular traditional Chinese medicines (TCMs), which is contained by more than 80 composite formulae. Modern researches indicate that phthalides, organic acids and their esters, polysaccharides are main chemical components related to the bioactivities and pharmacological properties of Danggui. Some of them, such as Z-ligustilide and ferulic acid, are selected as marker compounds to evaluate the quality of Danggui frequently. Because of the diversity of chemical structures and characters of these components, analytical methods of Danggui are various, including GC-MS, HPLC-DAD-MS, TLC, CE-DAD, and so on. Besides that, the development of analytical technology makes the quality control of Danggui more effective and reliable. Quality evaluation is from single or several components' analysis to fingerprinting, or in combination. Furthermore, bioactive components screening of Danggui has also attracted much attention, which will help us evaluate the selected marker components to some extent. In this paper, the literatures about the major phytoconstituents of Danggui, quality control and bioactive components screening methods have been reviewed. Main attention is given to the different methodologies developed to perform chemical analysis, including separation, detection and identification.  相似文献   
126.
YAN  Hongyuan  TIAN  Minglei  ROW  Kyung Ho 《中国化学》2009,27(11):2212-2216
A selective molecularly imprinted solid‐phase extraction procedure was developed for the selective separation of tanshinone I, tanshinone IIA, and cryptotanshinone from Radix Salvia Miltiorrhiza samples. Tanshinone IIA imprinted polymers (MIP) synthesized in ethanol‐dodecanol system show high affinity to tanshinone IIA and its structure analogs in aqueous environment and the affinity can be controlled by adjusting the intensity of the eluents. By using 60% water‐40% methanol (volume ratio) and 99.5% methanol‐0.5% trifluoroacetic acid (volume ratio) as washing and eluting solvents, most interferences originating from the salvia matrix were eliminated. The extracts were sufficiently clean enough to be directly injected into HPLC for further chromatographic analysis. Good linearity was obtained from 0.4 to 500.0 mg·L?1 (r2=0.999) with the relative standard deviations less than 4.2%. The mean recoveries of tanshinone IIA in Radix Salvia Miltiorrhiza were more than 85.6% at three different concentrations and the limits of detection were 0.06–0.09 mg·L?1. This method is a viable alternative tool to the existing HPLC methods for analyzing the content of the three tanshinones in Radix Salvia Miltiorrhiza samples.  相似文献   
127.
溶剂浮选法分离富集大黄中的有效成分   总被引:1,自引:0,他引:1  
采用溶剂浮选法对大黄提取液中的芦荟大黄素、大黄素、大黄酚以及大黄素甲醚进行了分离富集,并用高效液相色谱法分别测定了其含量。考察了料液浓度、浮选溶剂、浮选时间、浮选液pH值、氮气流速和电解质NaCl浓度对浮选效率的影响,并与泡沫浮选法和溶剂萃取法进行了比较。结果表明:溶剂萃取效果最差,泡沫浮选次之,溶剂浮选法分离富集效果最好。当料液浓度为6.4mg/mL,浮选时间为30min,浮选液pH一1~2,氮气流速为20mL/min,电解质NaCl浓度为0.4mol/L时,溶剂浮选效率最佳。  相似文献   
128.
利用化学计量学分辨方法和高效液相色谱法建立了黄芪中毛蕊异黄酮和芒柄花素的定量分析方法。色谱柱为Hypersic ODS柱(4.4mm×250mm,5μm),流动相为A:水含0.2%(V/V)醋酸,B:乙腈含0.2%(V/V)醋酸,线性梯度洗脱。借直观推导式演进特征投影(HELP)法分辨HPLC-DAD产生的二维数据得毛蕊异黄酮和芒柄花素的纯光谱和纯色谱,用总体积积分法定量分析其含量。毛蕊异黄酮和芒柄花素的校准曲线和相关系数分别为y=166.72x+127.8(r=0.9997)和y=178.39x+187.2(r=0.9993),线性范围分别为1.0—116.5μg·mL-1和1.2—112.5μg·mL-1,加标回收率分别在96.5%—98.7%和96.8%—98.5%之间。方法灵敏、选择性和可靠性好,可用于测定黄芪中毛蕊异黄酮和芒柄花素含量及质量控制。  相似文献   
129.
A rapid and sensitive liquid chromatography with tandem mass spectrometry method was developed and validated for simultaneous determination of puerarin, daidzin, daidzein, 3′‐hydroxy puerarin, and genistein in rat plasma after oral administration of Puerariae lobatae radix extract. The method of protein precipitation with acetonitrile was used for sample preparation. Chromatographic separation was achieved on a C18 column with the mobile phases of acetonitrile/water containing 0.1% formic acid. The analytes were detected by mass spectrometer with an electrospray ionization source operating in the negative ion mode. The linearity, precision, accuracy, dilution reliability, recovery, matrix effects, and stability of the method were within acceptable ranges. The developed method was successfully used to compare the pharmacokinetic characteristics of five analytes in normal and type 2 diabetics rats after oral administration of Puerariae lobatae radix extract. Several pharmacokinetic alterations were observed and this might be caused by the pathological state of type 2 diabetes.  相似文献   
130.
Astragali Radix (AR) is one of the well-known traditional Chinese medicines with a long history of medical use and a wide range of clinical applications. AR contains a variety of chemical constituents which can be classified into the following categories: polysaccharides, saponins, flavonoids, amino acids, and trace elements. There are several techniques to extract these constituents, of which microwave-assisted, enzymatic, aqueous, ultrasonic and reflux extraction are the most used. Several methods such as spectroscopy, capillary electrophoresis and various chromatographic methods have been developed to identify and analyze AR. Meanwhile, this paper also summarizes the biological activities of AR, such as anti-inflammatory, antioxidant, antitumor and antiviral activities. It is expected to provide theoretical support for the better development and utilization of AR.  相似文献   
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