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Zhang Q.,CAS Northwest Institute of Plateau Biology | Zhang Q.,University of Chinese Academy of Sciences | Hu N.,CAS Northwest Institute of Plateau Biology | Hu N.,University of Chinese Academy of Sciences | And 9 more authors.
Asian Journal of Chemistry

A pre-column derivatization method using 2-(11 H-benzo[a]carbazol-11-yl) ethyl 4-methylbenzenesulfonate (BCETS) as labeling reagent followed by HPLC with fluorescence detection and on line APCI/MS for the determination and quantitative analysis of fatty acids from safflower has been successfully developed. The fatty acids could be easily and quickly labeled by BCETS at 95 °C in the presence of K2CO3 as catalyst in DMF within 35 min. The derivatives exhibited excellent fluorescence property with excitation and emission wavelengths of 272 and 505 nm, respectively. The method displayed good selectivity, sensitivity, reproducibility and applicability. Qinghai and Xinjiang safflower (QHS and XJS), which were planted in different places in Qinghai province, were analyzed by the established method. The result showed the contents of total fatty acids, saturated fatty acids and unsaturated fatty acids from Qinghai safflower sample were all much higher than that from Xinjiang safflower sample, especially for Qinghai safflower sample planted in Datong county. The main unsaturated fatty acids were C18:1, C18:2 and C18:3 and the dominated saturated fatty acids were C16, C18 and C20, respectively. This work would be helpful for the safety assessment and quality control of the two kinds of safflowers. Source

Zhang Q.,CAS Northwest Institute of Plateau Biology | Zhang Q.,University of Chinese Academy of Sciences | Luan G.,CAS Northwest Institute of Plateau Biology | Luan G.,University of Chinese Academy of Sciences | And 10 more authors.
Journal of Separation Science

A method that involved the combination of pH-zone-refining counter-current chromatography and semipreparative reversed-phase liquid chromatography has been established for the preparative separation of alkaloids from Hypecoum leptocarpum. From 1.2 g of crude sample, 31 mg N-feruloyltyramine, 27 mg oxohydrastinine, 47 mg hydroprotopine, 25 mg leptopidine, and 18 mg hypecocarpine have been obtained. The structure of the new compound, hypecocarpine, is confirmed based on the analysis of spectroscopic data, including NMR, UV, and IR spectroscopy and positive electrospray ionization mass spectrometry. The known chemical structures were characterized on the basis of 1H and 13C NMR spectroscopy. The purities of the five alkaloids are all over 92.7% as determined by high-performance liquid chromatography. The alkaloids' cytotoxicity in breast cancer cells is assessed by using a Cell Counting Kit assay and their inhibitory effect on fatty acid synthase expression is assessed by a Western blot assay. These results suggest that leptopidine could suppress growth and induce cytotoxicity in breast cancer cells and that the cytotoxicity of leptopidine may be related to its inhibitory effect on fatty acid synthase expression. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim. Source

Li W.-C.,CAS Northwest Institute of Plateau Biology | Li W.-C.,University of Chinese Academy of Sciences | Wang X.-Y.,University of Chinese Academy of Sciences | Lin P.-C.,Qinghai University for Nationalities | And 8 more authors.
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences

High-speed counter-current chromatography (HSCCC) was successfully applied for the first time to isolate and purify four cis-trans isomers of coumaroylspermidine analogs from Safflower. HSCCC separation was achieved with a two-phase solvent system composed of chloroform-methanol-water (1:1:1, v/v/v) with the upper phase as the mobile phase. In a single run, a total of 1.3mg of N1, N5, N10-(E)-tri-p-coumaroylspermidine (EEE), 4.4mg of N1(E)-N5-(Z)-N10-(E)-tri-p-coumaroylspermidine (EZE), 7.2mg of N1(Z)-N5-(Z)-N10-(E)-tri-p-coumaroylspermidine (ZZE), and 11.5mg of N1,N5,N10-(Z)-tri-p-coumaroylspermidine (ZZZ) were obtained from 100mg of crude sample. High Performance Liquid Chromatography (HPLC) analysis showed that the purities of these four components are 95.5%, 98.1%, 97.5% and 96.2%, respectively. The chemical structures were identified by ESI-MS, 1H NMR and 13C NMR. © 2013 Elsevier B.V. Source

Yang H.,Key Laboratory for Plateau Crop Germplasm Innovation and Utilization of Qinghai Province | Yang H.,CAS Northwest Institute of Plateau Biology | Liu J.,CAS Northwest Institute of Plateau Biology | Chen S.,CAS Northwest Institute of Plateau Biology | And 2 more authors.
Journal of Natural Medicines

Gentiana straminea is the famous Tibetan folk medicine thought to cure various diseases. Historically, the Qinghai-Tibetan region has been considered as the geoauthentic production area of "Mahua Jiao," where large quantities of the medicine are grown. However, there is still little known about the phytochemical constituent spatial variation of this species. In order to find the differences between the main phytochemical constituents of G. straminea and to provide comprehensive information for quality evaluation, four main bioactive compounds (loganic acid, swertiamarin, gentiopicroside and sweroside) were analysed in 26 populations grown in areas with elevations ranging from 2320 to 4720 m across the Qing-hai-Tibetan Plateau. The results showed that the four phytochemical constitutes' concentrations varied greatly in the spatial profiling of the Qinghai-Tibetan region. Throughout the range of distribution of this species, no altitudinal, latitudinal or longitudinal trends have proven to be significant in any of the four constitutes' concentrations or their summation. Furthermore, hierarchical clustering analysis and statistical tests showed that four populations (Liu0609-18, Liu0609-15, Liu2006-13-9 and Liu0609-22) had total constitute contents that were higher than other populations. The spatial profiling of the four phytochemical constituents suggests that the geo-authentic producing area of this species exists at a few regions within the Qinghai province, which could be attributed to specific environmental or genetic factors. © The Japanese Society of Pharmacognosy and Springer Japan 2013. Source

Zhang Q.,CAS Northwest Institute of Plateau Biology | Zhang Q.,University of Chinese Academy of Sciences | Ma T.,CAS Northwest Institute of Plateau Biology | Ma T.,University of Chinese Academy of Sciences | And 10 more authors.
Journal of Chromatographic Science

High-speed counter-current chromatography (CCC) was firstly and successfully applied for the preparative separation and purification of alkaloids from crude extract of Hypecoum leptocarpum. After the measurement of partition coefficient of five target alkaloids in the two-phase solvent systems, the CCC was performed well with a two-phase solvent system composed of tetrachloromethane-chloroform-methanol-0.1 M HCl at a volume ratio of 1.5: 2.5: 3: 2 (V/V/V/V). The upper phase was used as the stationary phase, and the lower phase was used as the mobile phase. From 120 mg crude extract, 5 mg leptopidine, 32 mg oxohydrastinine, 27 mg (-)-N-methylanadine, 7 mg N-feruloyltyramine and 3 mg hypecoleptopine could be successfully separated. The amides alkaloid, N-feruloyltyramine, was firstly separated from H. leptocarpum. High-performance liquid chromatography analysis showed that the purity of each of the five target alkaloids was over 92%. Their chemical structures were confirmed by 1H-NMR and 13C-NMR data. © The Author 2015. Published by Oxford University Press. Source

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