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101.
102.
A novel method, using high-performance liquid chromatography combined with principal component analysis, was developed for the quality evaluation of danshen through simultaneous determination of seven components, namely danshensu, protocatechuic acid, protocatechuic aldehyde, salvianolic acid B, tanshinone I, cryptotanshinone and tanshinone IIA. These seven components were simultaneously separated on a Zorbax SB-C(18) column. The mobile phase consisted of 0.05% phosphoric acid water and methanol:acetonitrile (1:1) with a gradient elution, and the detection wavelength was set at 280 nm. Thirty samples of danshen and its substitutes from different sources were investigated by the established method. The results showed that the content of each analyte varied considerably in different danshen samples. Among the seven components tested, salvianolic acid B, tanshinone IIA, cryptotanshinone, tanshinone I, danshensu and protocatechuic aldehyde were proved suitable and representative as chemical markers for the quality control of danshen except for protocatechuic acid. Moreover, principal component analysis was used for the similarity evaluation of different samples, and it could be straightforward and reliable to differentiate danshen samples of different origins. In conclusion, simultaneous quantification of multiple components by high-performance liquid chromatography combined with principal component analysis would be a better strategy for the quality evaluation of danshen.  相似文献   
103.
建立了固相萃取(SPE)-定量核磁共振波谱(qNMR)技术测定板蓝根饮片中有效成分表告依春含量的方法.样品用水超声提取两次,采用SPE对提取液进行富集浓缩,用qNMR测定表告依春的含量.考察了样品预处理和qNMR实验条件对测定结果的影响,选择氘代二甲基亚砜为溶剂,用基准试剂邻苯二甲酸氢钾标定的2,3,5-三碘苯甲酸为内标,选择脉冲宽度P1=14.1 μs,延迟时间d1=5 s,扫描次数NS=256为qNMR定量测定表告依春的最佳实验条件.表告依春的定量峰为δ 5.365~5.399 (H-7b, d,1H).结果表明,日内测量精密度(RSD)为0.5%,日间精密度为0.8%,表告依春与三碘苯甲酸峰面积比与质量比的零截距标准曲线线性相关系数为0.9991,且斜率与理论值相符.根据响应值标准偏差和标准曲线斜率法确定此法测定表告依春的检测限(LOD)为0.05 mg/g;定量限(LOQ, S/N ≥ 150)为0.19 mg/g.包括样品提取过程的表告依春的回收率为97.4%~101.7%.采用本方法测定板蓝根饮片中的表告依春的含量为<0.19~1.26 mg/g.研究结果表明,采用SPE进行富集,扩大了qNMR的应用范围,可用于低含量复杂样品的定量分析.  相似文献   
104.
The effect of Radix Scutellariae treated on type 2 diabetic rats has been investigated by a liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS) based urinary quantitative approach. In this research, multiple reactions monitoring mode of MS/MS in LC-MS/MS analysis was used to quantitatively analyze the concentrations of 7 endogenous compounds in urine of normal control group, type 2 diabetic model group and Radix Scutellariae-treated group, and multivariate statistical analysis was utilized for MS data processing. The above-mentioned three groups can be distinguished via pattern recognition. The obtained results indicated that Radix Scutellariae affect the urinary metabolic profiling of type 2 diabetic rats on the polyol pathway, protein glycation reaction and amino acids metabolism pathway. According to these results, Radix Scutellariae should have the pharmacological effect on preventing or delaying the onset and progression of diabetes and its complications.  相似文献   
105.
Radix Polygalae, roots of Polygala tenuifolia or of Polygala sibirica, is a Chinese herbal medicine commonly used to prevent dementia. Reliable chemical markers for quality assurance of this herb are missing. Here, a high performance liquid chromatography method coupled with diode array detection was developed to simultaneously determine nine different phenols in Radix Polygalae, including sibiricose A(5), sibiricose A(6), glomeratose A, tenuifoliside A, glomeratose D, 3',6-di-O-sinapoyl sucrose ester, mangiferin, polygalaxanthone III, and polygalaxanthone XI. By using two different detection wavelengths in the HPLC analysis, the developed method was able to determine the phenols with excellent resolution, precision, and recovery. This established method was therefore applied to determine the amounts of phenols in thirty-two samples from different cultivation regions and harvest seasons in China, and significant variations were revealed. The amounts of phenols in the roots of P. tenuifolia collected in Shanxi and Shannxi Provinces were markedly higher than in roots collected from other Provinces. Moreover, the samples harvested in the spring contained higher contents of phenols than those collected in other seasons.  相似文献   
106.
An improved high‐performance liquid chromatography with diode array detection combined with accelerated solvent extraction method was used to simultaneously determine six compounds in crude and processed Radix Scrophulariae samples. Accelerated solvent extraction parameters such as extraction solvent, temperature, number of cycles, and analysis procedure were systematically optimized. The results indicated that compared with crude Radix Scrophulariae samples, the processed samples had lower contents of harpagide and harpagoside but higher contents of catalpol, acteoside, angoroside C, and cinnamic acid. The established method was sufficiently rapid and reliable for the global quality evaluation of crude and processed herbal medicines.  相似文献   
107.
采用基于超高效液相色谱与串联四极杆飞行时间质谱仪(Ultra-high performance liquid chromatography coupled with quadrupole time-of-flight mass spectrometry,UHPLC-Q-TOF MS)联用的代谢组学方法,通过分析大鼠尿液内源性代谢物的变化,研究黄芩-栀子药对治疗糖尿病肾病的作用机制。利用高脂高糖饲料喂养并腹腔注射链脲佐菌素(STZ)建立糖尿病大鼠模型。给药12周后,采用UHPLC-Q-TOF MS对正常对照组、模型组、黄芩-栀子药对治疗组的尿液样品进行代谢轮廓分析。利用正交偏最小二乘判别分析(Orthogonal partial least squares discriminant analysis,OPLS-DA)对实验数据进行分析,挑选出对各组分分离贡献较大(VIP>1,p<0.05)的化合物在Human Metabolome Database(HMDB)等数据库进行质谱信息匹配,共鉴定出糖尿病肾病潜在生物标记物31个,给药后回调生物标记物16个。研究结果表明,黄芩-栀子药对通过影响胆汁酸的合成与代谢、尿毒素代谢、能量代谢、色氨酸代谢、苯丙氨酸代谢、酪氨酸代谢等通路对糖尿病肾病起到治疗作用,其中胆汁酸的合成与代谢、尿毒素代谢和能量代谢可能是黄芩-栀子药对发挥治疗作用的主要途径。与单味药相比,配伍后的药对具有了新的药理作用。  相似文献   
108.
Coumarins are the primary bioactive ingredients in Radix Glehniae, named Beishashen in China, which possesses many pharmacological activities, including anticancer, anti‐inflammation and antivirus activities. In the present study, we employed a sensitive and selective high‐performance liquid chromatography–electrospray ionization–tandem mass spectrometry (HPLC‐ESI‐MS/MS) method for the quantification of nine coumarins in rat urine and bile: scopoletin ( 1 ), xanthotoxol ( 2 ), xanthotoxin ( 3 ), psoralen ( 4 ), isoimpinellin ( 5 ), bergapten ( 6 ), oxypeucedanin ( 7 ), imperatorin ( 8 ) and isoimperatorin ( 9 ). Pimpinellin ( 10 ) was used as the internal standard (IS). The urine and bile samples were pretreated by liquid–liquid extraction with ethyl acetate (EtOAc). The chromatographic separation was carried out on a C18 column with gradient elution. The detection of analytes was performed on a tandem mass system equipped with a turbo ion spray interface in positive mode using multiple‐reaction monitoring (MRM). The specificity, linearity, accuracy, precision, recovery, matrix effect and several stabilities were validated for coumarins in rat urine and bile samples. The results showed that this method is robust, specific and sensitive and it can successfully fulfill the requirements of the excretion study of the nine coumarins in Radix Glehniae. Copyright © 2010 John Wiley & Sons, Ltd.  相似文献   
109.
以H+-Mn2+-BrO-3-CH3COCH3-甘草组成的化学振荡体系,应用电化学工作站记录电位(E)随时间(t)的变化,绘制化学振荡曲线.通过考察反应条件及反应物的浓度等因素对振荡曲线的影响,优化最佳的振荡反应条件,计算反应的活化能,推断反应的机理.为利用此方法鉴别中草药及研究中药治疗疾病提供理论依据.  相似文献   
110.
建立了白芷中欧前胡素,异欧前胡素和氧化前胡素的液相色谱-串联质谱分析法。白芷提取液经Waters XTerra-C18(150mm×3.9 mm,5μm)色谱柱分离,以1mmol/L乙酸铵溶液和乙腈为流动相进行洗脱,以电喷雾正离子(ESI+)模式电离,多反应监测(MRM)模式检测,外标法定量。欧前胡素,异欧前胡素和氧化前胡素分别在0.05~10μg/mL,0.05~13μg/mL和0.1~120μg/mL范围内呈线性相关,相关系数(r)分别为0.9993,0.9991和0.9994,检出限分别为30,30和50 ng/mL,平均加标回收率为100.1%,99.4%和98.4%,相对标准偏差分别为2.2%,2.6%和2.8%(ρ=0.5μg/mL,n=6),该法可以满足同时检测白芷中欧前胡素,异欧前胡素和氧化前胡素的需求。  相似文献   
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