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Summary A capillary zone electrophoresis method for identification and determination of aesculin and aesculetin has been established
using borate-phosphate buffer containing 30% ethanol with on-column UV detection. A detailed investigation of the influence
of changes in borate concentration, pH, applied voltage, temperature and organic modifier was then carried out. For both aesculin
and aesculetin, a linear plot of migration time (MT) against borate concentration was obtained, and ln[measured peak area
(MA)] and lnMT both gave linear plots against ln(applied voltage) with correlation coefficient r>0.999, which also resulted
in a linear correlation between MA and MT (r≥0.9998) under varied voltage. Ethanol as organic modifier to the background electrolytes
helped in separating aesculin and aesculetin from other components in ash barks. The reproducibility with relative standard
deviation in MT and in normalized peak area(NA) and linearity based on NA against concentration were evaluated. Finally, the
method was successfully applied to monitor the quality of different ash barks and to compare the effect of sample preparation
on content of bioactive components in ash bark. Results indicate that CZE promises to be applicable to quality control of
traditional Chinese medicines containing aesculin and aesculetin. 相似文献
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A consecutive preparation method based upon accelerated solvent extraction (ASE) coupled with high‐speed counter‐current chromatography (HSCCC) was presented and aesculin was obtained from Cortex fraxinus. The extraction condition of ASE was optimized with response surface methodology; some significant parameters such as the solvent system and its stability, the amount of loading sample in HSCCC were also investigated. The original sample was first extracted with methanol at 105°C and 104 bar for 7 min using ASE, then the extracts were consecutively introduced into the HSCCC system and separated and purified with the same ethyl acetate/n‐butanol/water (7:3:10, v/v/v) solvent system for five times without further exchange and equilibrium. About 3.1 ± 0.2 mg/g in each time and total of 15.4 mg/g aesculin with purity over 95% was isolated from Cortex fraxinus. The results demonstrated that the consecutive preparation method was time and solvent saving and high throughput, it was suitable for isolation of aesculin from Cortex fraxinus, and also has good potential on the separation and purification of effective compounds from natural product. 相似文献
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Isolation and purification of coumarin compounds from Cortex fraxinus by high-speed counter-current chromatography 总被引:6,自引:0,他引:6
High-speed counter-current chromatography (HSCCC) was successfully used for the isolation and purification of coumarin compounds from Cortex fraxinus, the Chinese herbal drug. n-Butanol-methanol-0.5% acetic acid (5:1.5:5, v/v) was used as the two-phase solvent system. 14.3 mg of fraxin, 26.5 mg of aesculin, 5.8 mg of fraxetin and 32.4 mg of aesculetin with the purity of 97.6, 99.5, 97.2 and 98.7%, respectively were obtained from 150 mg of crude extracts of C. fraxinus in a single run. The structures of the isolated compounds were identified by 1H NMR and 13C NMR. 相似文献
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虚拟组分-人工神经网络用于中药紫外光度法中多组分的同时测定 总被引:1,自引:1,他引:0
采用虚拟组分自修正、自拟合的方法消除了干扰组分的影响,实现了人工神经网络(ANN)-紫外分光光度法不经分离的中药多组分浓度的同时测定。建立了包含训练网络和拟合网络的双网络ANN算法,提高了ANN算法的自学习、自判别能力,使复杂中草药体系多组分浓度预报的准确度大大提高。对21种不同来源的秦皮中秦皮甲素和秦皮乙素的含量进行了预测,预测结果与HPLC法相比较,以相对误差小于10%计,预测准确率大于90%。该法对秦皮甲素和秦皮乙素的测定精密度分别为0.37%,1.5%。 相似文献
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《Analytical letters》2012,45(18):2819-2832
The goal of this study was to optimize the parameters for capillary electrophoresis to separate and determine aesculin, aesculetin, umbelliferone, and dihydrocoumarin in plant materials. A simple and rapid capillary zone electrophoresis method is reported for this separation that required less than nine minutes. A bare fused silica capillary was employed using 20 mM borax in 5% methanol at pH 10.1 as the background electrolyte with an applied voltage of 30 kV at 27°C. Good linearity and reproducibility were obtained with high correlation coefficients. The analytes were determined by molecular absorption at 194 and 206 nm. Coumarins were determined in Aesculus hippocastanum L., Cichorium intybus L., Melilotus officinalis L., and Juniperus communis L. “Pendula.” The concentrations of aesculin and aesculetin were 3.07 and 6.31 mg g?1 in Aesculus hippocastanum. In Cichorium intybus, the aesculetin concentration was 2.42 mg g?1. The dihydrocoumarin concentration was 0.54 mg g?1 in Melilotus officinalis, and the concentration of umbelliferone was 0.58 mg g?1 in Juniperus communis “Pendula.” 相似文献
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建立了在线测定秦皮甲素和秦皮乙素水解反应速率常数的扫集-流动注射-胶束电动色谱新方法.该方法进样频率为12次/h,可在5 min内完全分离反应体系中的所有组分,30 min即可完成一个温度下的反应速率常数测定.由于该在线测定方法不需要终止水解反应,通过一次连续进样分析得到水解反应过程电泳谱图,从而可以获得水解反应过程中的一些信息.在最佳条件时,用0.1 mol/L KOH为催化剂,测得25,30,35,40和45C时秦皮甲素的水解反应速率常数分别为3.65×10-2/min、5.24× 10-2/min、7.12× 10-2/min、10.5×10-2/min和16.3×10-2/min,活化能为58.57 kJ/mol.用10 mmol/L KOH为催化剂,测得15,20,25,30和35℃时秦皮乙素的水解反应速率常数分别为2.26× 10-2/min,2.85× 10-2/min,3.55× 10-2/min,4.38× 10-2/min和5.29× 10-2/min,活化能为31.55 kJ/mol. 相似文献
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Philipp Drosky Madlen Sander Kazuhide Nakata Hans‐Ullrich Siehl Klaus‐Peter Zeller Stefan Berger Dieter Sicker 《Chemie in Unserer Zeit》2014,48(6):450-459
The closely related glycosides fraxin and esculin have been isolated in pure form from an ash bark extract by gel permeation chromatography. This challenging separation is a prime example for the preparative value of a crosslinked dextran gel. Silicagel 60 only leads to pure esculin. The terms optical brighteners and fluorescence are discussed. All analytical spectra were recorded and are reproduced and interpreted either in the main part or in the supporting information. The project is a follow up of the recent book “Classics in Spectroscopy” by S. Berger und D. Sicker (Wiley‐VCH 2009). 相似文献
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