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71.
Consonni R Cagliani LR Benevelli F Spraul M Humpfer E Stocchero M 《Analytica chimica acta》2008,611(1):31-40
This work presents the capability of NMR spectroscopy combined with Chemometrics in predicting the ageing of Balsamic and Traditional Balsamic Vinegar of Modena. The need of an analytical method is an important requirement for both research oriented and commercial evaluation of these very valuable products. 1H NMR spectroscopy, based on the advantage of rapid sample analysis without any manipulation or derivatization, is here proposed as a valid tool to describe Balsamic and Traditional Balsamic Vinegar of Modena. For this purpose, 72 reliable samples, were divided into three different groups according to their ageing process: young (<12 years), old (>12 and <25 years) and extra old (>25 years). Hierarchical Projection to Latent Structures Discriminant Analysis (PLS-DA) allowed us to characterize the ageing process. Variables showing the largest VIP (Variable Importance in the Projection) were extracted from PLS-DA model, thus shedding lights onto the role played by specific compounds in this complex ageing process. Two robust classification models, were built by PLS-DA and Naïve Bayes classifier and compared to prove the accuracy of the representation on both training and test sets. The predictions obtained for 41 “unknown” vinegar samples with these both methods gave more than 80% agreement among them. 相似文献
72.
基于高压制备液相的多维色谱技术在中药分离纯化中的应用 总被引:1,自引:0,他引:1
中药物质基础复杂,对其活性成分的分离一直是中药研究的难题.基于高压制备液相的多维色谱系统在高压制备液相色谱的基础上,结合了多种分离技术,极大地提高了色谱系统的分离性能和分离效率,更有利于对物质基础复杂的中药样品进行分离纯化.本文介绍了基于高压制备液相系统的多维色谱系统的基本原理、分离模式以及关键技术,并综述了其在中药分离纯化中的应用. 相似文献
73.
《Comptes Rendus Chimie》2016,19(9):1056-1061
Cinnamosma fragrans is an endemic plant used in traditional medicine. The geographical distribution of this Canellaceae is limited to Madagascar. Few phytochemical investigations performed on this plant have described atypical sesquiterpenes including drimane-type sesquiterpenes, drimane-type sesquiterpene lactones, sesquiterpene lactams and coloratane sesquiterpenes. These original sesquiterpenes are associated with pharmaceutical activities. 相似文献
74.
Separation and determination of flavonoids in three traditional chinese medicines by capillary electrophoresis with amperometric detection
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Wei Wang Ping Lin Lihong Ma Kaixuan Xu Xiuli Lin 《Journal of separation science》2016,39(7):1357-1362
Flavonoids are important active ingredients in many traditional Chinese medicines. In this paper, capillary electrophoresis with amperometric detection was employed to separate and detect eight flavonoids, rutin, quercetrin, quercetin, kaempferol, kaempferide, catechin, apigenin, and luteolin, in a home‐made capillary electrophoresis device. Under the separation voltage of 2000 V, the eight flavonoids could be completely separated within 33 min in 18 mM borax running buffer at pH 10.2. Good linear relationships were obtained for all analytes and the detection limits for flavonoids ranged from 0.46 to 0.85 μM. Then, the method was applied to separate and determine the flavonoids in three traditional Chinese medicines, hippophae rhamnoides, hypericum perforatum, and cacumen platycladi. Finally, rutin, kaempferol, quercetin, and quercetrin were discovered in these medicines and the concentrations ranged from 0.28 to 9.94 mg/g. The recoveries of flavonoids ranged from 84.7 to 113%, which showed the high reliability of this method. 相似文献
75.
Simultaneous quantitation of 14 active components in Yinchenhao decoction by using ultra high performance liquid chromatography with diode array detection: Method development and ingredient analysis of different commonly prepared samples
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YaXiong Yi Yong Zhang Lu Lu Tong Zhang Yuan Zhao XiaoJun Xu YuXin Zhang 《Journal of separation science》2016,39(21):4147-4157
We developed a novel quantitative analysis method based on ultra high performance liquid chromatography coupled with diode array detection for the simultaneous determination of the 14 main active components in Yinchenhao decoction. All components were separated on an Agilent SB‐C18 column by using a gradient solvent system of acetonitrile/0.1% phosphoric acid solution at a flow rate of 0.4 mL/min for 35 min. Subsequently, linearity, precision, repeatability, and accuracy tests were implemented to validate the method. Furthermore, the method has been applied for compositional difference analysis of 14 components in eight normal‐extraction Yinchenhao decoction samples, accompanied by hierarchical clustering analysis and similarity analysis. The result that all samples were divided into three groups based on different contents of components demonstrated that extraction methods of decocting, refluxing, ultrasonication and extraction solvents of water or ethanol affected component differentiation, and should be related to its clinical applications. The results also indicated that the sample prepared by patients in the family by using water extraction employing a casserole was almost same to that prepared using a stainless‐steel kettle, which is mostly used in pharmaceutical factories. This research would help patients to select the best and most convenient method for preparing Yinchenhao decoction. 相似文献
76.
Liquid chromatography with mass spectrometry and NMR spectroscopy based discovery of cytotoxic principles from Daphne tangutica Maxim 总被引:1,自引:0,他引:1
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Xinzhou Yang Mi Huang Sijian Zheng Xinhua Ma Dingrong Wan Yunjiang Feng 《Journal of separation science》2016,39(11):2179-2187
An ethyl acetate extract from the barks of the ethnic Chinese medicine Daphne tangutica Maxim. exhibited antihepatocellular carcinoma activity against HepG2 and Hep3B cell lines. By using high‐performance liquid chromatography based activity profiling in combination with offline liquid chromatography with mass spectrometry and NMR analysis, we rapidly identified ten major components of the extract, including seven active principles, coumarins ( 1–4 ) and biscoumarins ( 7, 8, 10 ), along with three inactive flavonoids ( 5, 6, 9 ). This study demonstrated that our combined protocol can be used as an important strategy for chemical profiling, dereplication as well as the identification of bioactive compounds from herbal medicines. 相似文献
77.
Bioassay‐guided isolation of an active compound with protein tyrosine phosphatase 1B inhibitory activity from Sargassum fusiforme by high‐speed counter‐current chromatography
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Miao Wang Xinfeng Guo Haoquan Li Yi Wang Hong Guo Yi Yang Jing Tian 《Journal of separation science》2016,39(22):4408-4414
A rapid and efficient method using high‐speed counter‐current chromatography was established for the bioassay‐guided separation of an active compound with protein tyrosine phosphatase 1B inhibitory activity from Sargassum fusiforme. Under the bioassay guidance, the ethyl acetate extract with the best IC50 value of 0.37 ± 0.07 μg/mL exhibited a potential protein tyrosine phosphatase 1B inhibitory activity, which was further separated by high‐speed counter‐current chromatography. The separation was performed with a two‐phase solvent system composed of n‐hexane/methanol/water (5:4:1, v/v). As a result, dibutyl phthalate (19.7 mg) with the purity of 95.3% was obtained from 200 mg of the ethyl acetate extract. Its IC50 was 14.05 ± 0.06 μM, which was further explained by molecular docking. The result of molecular docking showed that dibutyl phthalate enfolded in the catalytic site of protein tyrosine phosphatase 1B. The main force between dibutyl phthalate and protein tyrosine phosphatase 1B was the hydrogen bond interaction with Gln266. In addition, hydrogen bond, van der Waals force and hydrophobic interaction with the amino acids (Ala217, Ile219, and Gly220) were also responsible for the stable protein‐ligand complex. 相似文献
78.
Ultrafiltration‐LC–MS combined with semi‐preparative HPLC for the simultaneous screening and isolation of lactate dehydrogenase inhibitors from Belamcanda chinensis
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Senlin Li Sainan Li Ying Tang Chunming Liu Lina Chen Yuchi Zhang 《Journal of separation science》2016,39(23):4533-4543
Stroke represents the fourth leading cause of death in the USA and the second leading cause of death worldwide. Lactate dehydrogenase inhibitors are widely used in the treatment of ischemic stroke and natural products are considered a promising source of novel lactate dehydrogenase inhibitors. In this study, we used PC12 cells to determine the protective effect of extracts from the herb Belamcanda chinensis following toxic challenge. Using ultrafiltration high‐performance liquid chromatography coupled with photo‐diode array detection and electrospray ionization mass spectrometry, we screened and identified isoflavonoids from Belamcanda chinensis extracts. Semi‐preparative high‐performance liquid chromatography was then applied to separate and isolate the active constituents. Using these methods, we identified six major compounds in Belamcanda chinensis as lactate dehydrogenase inhibitors: tectoridin, iristectorin A, iridin, tectorigenin, irigenin, and irisflorentin, which were then isolated to >92% purity. This is the first report that Belamcanda chinensis extracts contain potent lactate dehydrogenase inhibitors. Our results demonstrate that the systematic isolation of bioactive components from Belamcanda chinensis guided by ultrafiltration high‐performance liquid chromatography coupled with photo‐diode array detection and electrospray ionization mass spectrometry represents a feasible and efficient technique that could be extended for the identification and isolation of other enzyme inhibitors. 相似文献
79.
Determination of sophoraflavanone G and kurarinone in rat plasma by UHPLC–MS/MS and its application to a pharmacokinetic study
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This study aimed to develop and validate a simple and sensitive ultra high performance liquid chromatography tandem mass spectrometry method for the simultaneous determination of sophoraflavanone G and kurarinone in rat plasma by using rutin as the internal standard. Then, the developed method was applied to investigate the pharmacokinetics of sophoraflavanone G and kurarinone in rats after dosing the flavonoid extract from Sophora flavescens. Plasma samples were processed using a liquid–liquid extraction procedure with ethyl acetate. The analysis was performed on a triple quadrupole tandem mass spectrometer by multiple reaction monitoring with an electrospray ionization source in negative ionization mode. Quantitative ion transitions of m/z 423.2→161.2, 437.2→161.1, and 609.3→300.3 were monitored for sophoraflavanone G, kurarinone, and rutin, respectively. The calibration curves of the two analytes exhibited good linearity (r2>0.9923) over the range of 0.1–200 ng/mL for sophoraflavanone G and 0.1–1000 ng/mL for kurarinone. Relative standard deviations were less than 13.2% for the intra‐ and inter‐day precisions and no more than 12.6% for the recovery, showing good precision and satisfactory accuracy of the developed method. The validated method was successfully applied to the pharmacokinetic study of sophoraflavanone G and kurarinone after a single intravenous (25 mg/kg) and oral (500 mg/kg) administration of the flavonoid extract from S. flavescens, and the absolute bioavailability for sophoraflavanone G and kurarinone was about 36 and 17%, respectively. 相似文献
80.
Differentiation of essential oils in Atractylodes lancea and Atractylodes koreana by gas chromatography with mass spectrometry
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Qiutao Liu Shanshan Zhang Xihui Yang Ruilin Wang Weiying Guo Weijun Kong Meihua Yang 《Journal of separation science》2016,39(24):4773-4780
Atractylodes rhizome is a valuable traditional Chinese medicinal herb that comprises complex several species whose essential oils are the primary pharmacologically active component. Essential oils of Atractylodes lancea and Atractylodes koreana were extracted by hydrodistillation, and the yield was determined. The average yield of essential oil obtained from A. lancea (2.91%) was higher than that from A. koreana (2.42%). The volatile components of the essential oils were then identified by a gas chromatography with mass spectrometry method that demonstrated good precision. The method showed clear differences in the numbers and contents of volatile components between the two species. 41 and 45 volatile components were identified in A. lancea and A. koreana, respectively. Atractylon (48.68%) was the primary volatile component in A. lancea, while eudesma‐4(14)‐en‐11‐ol (11.81%) was major in A. koreana. However, the most significant difference between A. lancea and A. koreana was the major component of atractylon and atractydin. Principal component analysis was utilized to reveal the correlation between volatile components and species, and the analysis was used to successfully discriminate between A. lancea and A. koreana samples. These results suggest that different species of Atractylodes rhizome may yield essential oils that differ significantly in content and composition. 相似文献