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《Biomedical chromatography : BMC》2017,31(11)
A simple and specific high‐performance liquid chromatographic method has been developed and validated to simultaneously determine seven secoiridoid glucosides for the first time. Three of them were separated from the ethanolic extract of the roots of Ilex pubescens for the first time, namely nuezhenide A, ligusides B and oleonuezhenide. In quantitative analysis, all of the calibration curves showed good linear regression (r > 0.999) within the tested ranges, and the mean recoveries of three different concentrations ranged from 97.6 to 101.2%. The limit of detection and limit of quantification were <4.18 and 11.63 ng mL−1, respectively. The relative standard deviation for repeatability and the precision of seven analytes were <3.4 and 1.9%, respectively. The established method was successfully applied to simultaneous determination of seven secoiridoid glucosides in 11 batches of samples collected from different habitats in China. 相似文献
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Wen-Wen Zhao Ke Zan Jing-Yue Wu Wei Gao Jie Yang Yin-Ying Ba 《Natural product research》2019,33(17):2435-2439
One new triterpenoid (1) and seven known analogues (2–8) were isolated from the leaves of Ilex hainanensis Merr.. Their structures were established by analysis of their MS, 1D and 2D NMR spectroscopic data and comparison with those in the literature. The antibacterial activity of compounds 1–8 were evaluated by determination of minimum inhibitory concentration using twofold microdilution broth method against Streptococcus mutans ATCC 25175 (Gram-positive) and Fusobacterium nucleatum ATCC 10953 (Gram-negative). Compounds 3 and 5 showed significant antibacterial activity against S. mutans in concentration of 9.7 μg/mL, while showed little antibacterial activity against F. nucleatum. On the contrary, the inhibitory activity of compounds 1, 2 and 6 against F. nucleatum were higher than them against S. mutans. 相似文献
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Phytochemical examination on the leaves of Ilex cornuta Lindl. (Aquifoliaceae) resulted in the isolation and identification of lupeol (I), 3β-hydroxylup-20(29)-en-30-al (II), oleanolic acid (III), and β-sitosterol-β-D-glucoside (IV). 相似文献
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Assis Jacques R dos Santos Freitas L Flores Peres V Dariva C de Oliveira JV Bastos Caramão E 《Journal of separation science》2006,29(18):2780-2784
The objective of this work was to investigate the extraction of Ilex paraguariensis leaves by means of three extraction techniques: pressurized liquid extraction (PLE, also called accelerated solvent extraction – ASE), maceration, and sonication. Samples of mate tea leaves were collected from an experiment conducted under agronomic control at Indústria e Comércio de Erva‐Mate Bar?o LTDA, Brazil. Six solvents with increasing polarities (n‐hexane, toluene, dichloromethane, ethyl acetate, acetone, and methanol) were used in this investigation. Chemical analysis of the extracts was performed by GC coupled with a mass spectrometer detector. The identification and quantification were accomplished by coinjections of certified standards. The results showed that no significant differences in the qualities of the extracts were noticed regarding the extraction methods. On the other hand, the PLE technique was found to be more effective for the extractions of caffeine, phytol, palmitic, and stearic acid. The use of PLE led to a significant decrease in the total extraction time, amount of solvent consumption, and manipulation of samples compared to maceration and ultrasound‐assisted extraction methods. 相似文献
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Yue Zhang Lu‐Jun Li Peng Zhang Hui‐Fang Pi Han‐Li Ruan Ji‐Zhou Wu 《Helvetica chimica acta》2011,94(12):2207-2214
Three new triterpenoid saponins with an 18,19‐secours‐13(18)‐ene skeleton, dunnianaolactones A–C ( 1 – 3 , resp.), together with nine known compounds i.e., the ursane‐type triterpene saponin 4 , the two benzofuran lignans 5 and 6 , five flavonoid glycosides, and 4‐hydroxybenzoic acid, were isolated from the leaves of Ilex dunniana Levl . (Aquifoliaceae). Their structures were elucidated by means of spectroscopic and chemical methods. The configuration of dunnianaolactone A ( 1 ) was further confirmed by X‐ray crystal‐structure analysis. 相似文献
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AbstractA pair of new diastereoisomeric flavan, containing an additional phenylpropanoid (C6–C3) unit in the molecule, has been isolated from the leaves of Ilex centrochinensis. Their structures were identified by extensive spectral analysis and comparison with the data of known analogues. 相似文献
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新三萜及其皂甙化学结构的NMR研究 总被引:6,自引:0,他引:6
从广东产的苦丁茶(Ilex kudincha)中分离出一个新三萜及三个新皂甙.用多种磁共振方法并结合其它结构信息,研究并确定了它们的化学结构,并对其进行了全归属. 相似文献