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为了对比野生与种植青海川西獐牙菜中微量元素的变化,分别采集野生川西獐牙菜与种植青海川西獐牙菜种子采收前后的全植株,采用原子吸收光谱仪测定了其铜、锌、铁、锰、钴等微量元素含量。结果表明,野生川西獐牙菜较种植青海川西獐牙菜中微量元素含量高,种植川西獐牙菜在成熟种子采收后较采收前(花果期)铁、锰、钴、锌等元素含量高。 相似文献
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川西獐牙菜及制剂中齐墩果酸的高效液相色谱测定 总被引:3,自引:0,他引:3
中药及制剂中齐墩果酸分离测定的色谱方法的色谱条件是:ODS柱,甲醇一水(90:10V/V)为流动相,紫外检测器检测波长207nm。本研究为中药资源开发制剂的质量控制提供了简便、灵敏、准确、快速的分离测定方法。 相似文献
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《Journal of separation science》2017,40(11):2515-2521
In our present study, two groups of xanthones isomers (1‐hydroxy‐3,5,8‐trimethoxyxanthone and 1‐hydroxy‐3,7,8‐trimethoxyxanthone; 1,8‐dihydroxy‐3,7‐dimethoxyxanthone and 1,8‐dihydroxy‐3,5‐dimethanolxanthone) and other two xanthones (3‐methoxy‐1,5,8‐trihydroxyxanthone and 3,5‐dimethoxy‐1‐hydroxyxanthone) were separated from Swertia franchetiana . First, a solvent system composed of petroleum ether/methanol/water (2:1:0.6, v/v) was developed for the liquid–liquid extraction of these xanthones from the crude extract. Then, an efficient method was established for the one‐step separation of these six xanthones by high‐speed countercurrent chromatography using n‐hexane/ethyl acetate/methanol/ethanol/water (HEMEW; 6:4:4:2:4, v/v) as the solvent system. The results showed that liquid–liquid extraction could be well developed for efficient enrichment of target compounds. Additionally, high‐speed countercurrent chromatography could be a powerful technology for separation xanthones isomers. It was found ethanol could be a good methanol substitute when the HEMEW system could not provide good separation factors. 相似文献
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Chang-An Geng Xue-Mei Zhang Zhi-Yong Jiang Jun Zhou Ji-Jun Chen 《Tetrahedron letters》2010,51(18):2483-1825
Swerilactones E (1), F (2), and G (3), three unusual lactones with a phenyl group, were isolated from the traditional Chinese herb of Swertia mileensis. Their structures were determined based on extensive spectroscopic analysis and X-ray single crystal crystallography. Our anti-HBV assay on the Hep G 2.2.15 cell line in vitro showed that compounds 1 and 2 exhibited significant inhibitory activities against the secretion of HBsAg with IC50 of 0.22 and 0.70 mM and HBeAg with IC50 of 0.52 and >6.78 mM, respectively. 相似文献
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GaoFeng Shi RunHua Lu YunShang Yang ChunLei Li AiMei Yang LiXiang Cai 《Journal of chemical crystallography》2005,35(2):135-139
In order to study the relationship between biological and pharmacological activities with their structures, a series of tri-, tetra-oxygenated xanthones including 1-hydroxyl-2,3,4,7-tetramethoxy xanthone 1, 1-hydroxyl-2,3,4,5-tetramethoxyl xanthone 2, 1-hydroxyl-3,5-dimethoxy xanthone 3, 1,8-dihydroxyl-3,5-dimethoxyl xanthone 4, 1,5,8-trihydroxyl-3-methoxy xanthone 5 has been isolated from Swertia chirayita. Their structures were established on the basis of spectral and chemical evidence. The crystal structure of 5 was also investigated by single crystal X-ray diffraction analysis. It crystallizes in the triclinic system, space group P
, with a = 7.1540(10) Å, b = 7.520(2)
Å, c = 10.671(2) Å, V = 562.7(2) Å3, = 86.50(3), = 80.06(3), = 85.00(3), Z = 2, Dc = 1.618 g m–3, Rint = 0.0230, wR(F2) = 0.1028, F(000) = 284. The molecular structure is nearly plane and four substituents are much closer to the plane of the molecule. Compound 5 also shows three intermolecular hydrogen bonds. A recent study shows that phenolic hydroxyls in xanthones are the main active groups capable of scavenging OH and O2. 相似文献
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Zhi Xin LIAO Yu Lin LI Ming Kui WANG Li Sheng DING* Yao Zu CHEN State Key Laboratory of Applied Organic Chemistry Lanzhou University Lanzhou Northwest Plateau Institute of Biology Chinese Academy of Sciences Xining Chengdu 《中国化学快报》2001,(5)
Swertia tetraptera Maxim. is a high altitude perennial plant growing on grassy and moist meadows in the Qinhai-Xizang Plateau. It is used in Tibetan folk medicine for the treatment of hepatic, choleric and inflammatory disease1. In this paper, we report the structure elucidation of two new xanthone glycosides named tetraswerosides A ( 1 ) and B ( 2 ) isolated from the whole plant of Swertia tetraptera.Figure 1 The key HMBC correlations for 1Compound 1 was obtained as yellow amorphous sol… 相似文献
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Simultaneous determination of oleanolic acid,ursolic acid,quercetin and apigenin in Swertia mussotii Franch by capillary zone electrophoresis with running buffer modifier 下载免费PDF全文
Ruibin Gao Litao Wang Yan Yang Jingman Ni Liang Zhao Shuqing Dong Mei Guo 《Biomedical chromatography : BMC》2015,29(3):402-409
The method of capillary zone electrophoresis (CZE) with direct UV detection was developed for the determination of oleanolic acid, ursolic acid, quercetin and apigenin. and then for the first time successfully applied to the analysis of four analytes in Swertia mussotii Franch and its preparations. Various factors affecting the CZE procedure were investigated and optimized, and the optimal conditions were: 50 × 10?3 mol/L borate‐phosphate buffer (pH 9.5) with 5.0 × 10?3 mol/L β‐cyclodextrin, 15 kV separation voltage, 20 °C column temperature, 250 nm detection wavelength and 5 s electrokinetic injection time (voltage 20 psi). Under the conditions, oleanolic acid, ursolic acid, quercetin and apigenin could be determined within the test ranges with a good correlation coefficient (r2 > 0.9991). The limits of detection for conditions, oleanolic acid, ursolic acid, quercetin and apigenin were 0.3415, 0.2003, 0.0062 and 0.2538 µg/mL, respectively, and the intra‐ and inter‐day relative standard deviations were no more than 4.72%. This procedure provided a convenient, sensitive and accurate method for simultaneous determination of oleanolic acid, ursolic acid, quercetin and apigenin in S. mussotii Franch. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
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Characterization of metabolites of sweroside in rat urine using ultra‐high‐performance liquid chromatography combined with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry and NMR spectroscopy 下载免费PDF全文
Han Han Wenliang Zeng Chunyong He S. W. Annie Bligh Qing Liu Li Yang Zhengtao Wang 《Journal of mass spectrometry : JMS》2014,49(11):1108-1116
Sweroside, a major active iridoid in Swertia pseudochinensis Hara, is recognized as an effective agent in the treatment of liver injury. Based on previous reports, the relatively short half‐life (64 min) and poor bioavailability (approximately 0.31%) in rats suggested that not only sweroside itself but also its metabolites could be responsible for the observed hepato‐protective effect. However, few studies have been carried out on the metabolism of sweroside. Therefore, the present study aimed at identifying the metabolites of sweroside in rat urine after a single oral dose (100 mg/kg). With ultra‐high‐performance liquid chromatography coupled with electrospray ionization quadrupole time‐of‐flight tandem mass spectrometry (UHPLC/Q‐TOF‐MS), the metabolic profile revealed 11 metabolites in rat urine, including phase I, phase II and aglycone‐related products. The chemical structures of metabolites were proposed based on accurate mass measurements of protonated or deprotonated molecules and their fragmentation patterns. Our findings showed that the aglycone of sweroside (M05) and its glucuronide conjugate (M06) were principal circulating metabolites in rats. While several other metabolic transformations, occurring via reduction, N‐heterocyclization and N‐acetylation after deglycosylation, were also observed. Two metabolites (M05 and M06) were isolated from the rat urine for structural elucidation and identifcation of reaction sites. Both M05 and M06 were characterized by 1H, 13C and two‐dimensional nuclear magnetic resonance (NMR) spectroscopy. UHPLC/Q‐TOF‐MS analysis has provided an important analytical platform to gather metabolic profile of sweroside. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献