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61.
新疆红柳花中红色素的提取及理化性质的研究 总被引:3,自引:0,他引:3
报道了新疆红柳花中红色素的提取及物理化学性质的研究,为红柳花红色素的提取和利用提供了科学依据。 相似文献
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63.
Comparative pharmacokinetics and tissue distribution of schisandrin,deoxyschisandrin and schisandrin B in rats after combining acupuncture and herb medicine (schisandra chinensis)
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Xiaoyan Wu Yuan Zhou Fangzhou Yin Guoliang Dai Lin Li Bin Xu De Ji Yong Sun Chunqin Mao Tulin Lu 《Biomedical chromatography : BMC》2014,28(8):1075-1083
Recently, combination therapy with acupuncture and medicine as a practical strategy to treat diseases has gained increasing attention. The present study aimed to investigate whether acupuncture stimulation at ST.36 had a potential impact on the pharmacokinetics and tissue distribution of lignans. An HPLC‐ESI/MS analytical method was established and successfully applied to a comparative study of drug concentration in plasma and tissues of three lignans. The parameters area under the plasma concentration–time curve from time zero to the final measurable point and from time zero to infinity, and peak concentration were significantly increased, with a prolonged mean residence time and a corresponding decrease in clearance in comparision with the Schisandra‐alone group. Additionally, tissue concentrations of three lignans were improved in the group with acupuncture, especially in liver. The results indicated that acupuncture has a synergistic effect on the pharmacokinetics and tissue distribution of the three lignans, which could postpone their elimination, resulting in a longer blood circulating time in rat plasma and prolonged residence time in target tissues, leading to higher tissue concentration. The findings provide some scientific evidence for the mechanism of the combined use of acupuncture and herbal medicine. Furthermore, we suggest that acupuncture and its combination with herbal medicine should be investigated further as a possible adjuvant therapy in clinical treatment for liver injury. Copyright © 2014 John Wiley & Sons, Ltd. 相似文献
64.
采用原子荧光光谱法测定了产于吉林长白山北五味子中的重金属元素的含量.建立了测定各元素的最佳实验条件,并讨论了酸度、还原剂等条件对实验的影响.结果表明,As、Hg、Se和Cd的检出限分别为0.17 ng·mL-1、0.10 ng·mL-1、0.011 ng·mL-1和0.61 ng· mL-1.各元素的回收率分别为90.... 相似文献
65.
A sensitive HPLC–MS/MS method for the simultaneous determination of anemoside B4, anemoside A3 and 23‐hydroxybetulinic acid: Application to the pharmacokinetics and liver distribution of Pulsatilla chinensis saponins
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《Biomedical chromatography : BMC》2018,32(3)
Pulsatilla chinensis saponins, the major active components in the herb, have drawn great attention as potential hepatitis B virus infection and hepatoma treatments. Here, a sensitive and accurate HPLC–MS/MS method was established for simultaneous determination of three saponins – anemoside B4, anemoside A3 and 23‐hydroxybetulinic acid – in rat plasma and liver, and fully validated. The method was successfully applied to a pharmacokinetics and liver distribution study of P. chinensis saponins. Consequently, 23‐hydroxybetulinic acid, with an extremely low content in the P. chinensis saponins, exhibited the highest exposure in the liver and in sites before and after hepatic disposition, namely, in the portal vein plasma and systemic plasma, followed by anemoside B4, which showed the highest content in the herb, whereas anemoside A3 displayed quite limited exposure. The hepatic first‐pass effects were 71% for 23‐hydroxybetulinic acid, 27% for anemoside B4 and 37% for anemoside A3, corresponding to their different extents of liver distribution. To our knowledge, this is the first investigation on the liver first‐pass effect and distribution of P. chinensis saponins to date. These results also provide valuable information for the understanding of the pharmacological effect of P. chinensis saponins on liver diseases. 相似文献
66.
Rapid separation of polysaccharides using a novel spiral coil column by high‐speed countercurrent chromatography
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The separation of polysaccharides is time consuming. We developed and optimized a type‐J counter‐current chromatography system with a novel tri‐rotor spiral coil column for the rapid separation of polysaccharides. The optimal composition of an aqueous PEG1000/K2HPO4/KH2PO4 system was found to be 14:16:14 w/w/w where the lower phase was the mobile phase. Optimal performance was achieved at a column rotational speed, temperature, and flow rate of 1200 rpm, 45°C, and 3.0 mL/min, respectively. The mobile phase was pumped from the inner terminal in a ‘‘head‐to‐tail’’ elution mode. Polysaccharide LCP‐1 (10.7 mg) was successfully obtained in high purity in one step from 50.0 mg of a crude polysaccharide extracted from the lychee fruit (Litchi chinensis) within 100 min. LCP‐1 possess a number‐average molecular weight and weight‐average molecular weight of 1.05 × 105 and 1.59 × 105 kDa, respectively. The monosaccharide composition consists of the molar ratio of glucose, galactose, and arabinose of 1.3:3.5:1. 相似文献
67.
Chunxia Lu Xiaoling Luo Liliang Lu Hongmin Li Xia Chen Yong Ji 《Journal of separation science》2013,36(5):959-964
In recent years, ionic liquids have become increasingly attractive as ‘green solvents’ used in the extraction of bioactive compounds from natural plant. However, the separation of ionic liquid from the target compounds was difficult, due to their low vapour pressure and high stabilities. In our study, ionic liquid‐based ultrasonic and microwave‐assisted extraction was used to obtain the crude tannins, then the macroporous resin adsorption technology was further employed to purify the tannins and remove the ionic liquid from crude extract. The results showed that XDA‐6 had higher separation efficiency than other tested resins, and the equilibrium experimental data were well fitted to Langmuir isotherms. Dynamic adsorption and desorption were performed on XDA‐6 packed in glass columns to optimise the separation process. The optimum conditions as follows: the ratio of column height to diameter bed was 1:8, flow rate 1 BV/h (bed volume per hour), 85% ethanol was used as eluant while the elution volume was 2 BV. Under the optimised conditions, the adsorption and desoption rate of tannins in XDA‐6 were 94.81 and 91.63%, respectively. The content of tannins was increased from 70.24% in Galla chinensis extract to 85.12% with a recovery of 99.06%. The result of ultra‐performance liquid chromatography (UPLC)‐MS/MS analysis showed that [bmim]Br could be removed from extract. 相似文献
68.
Jiaye Wang Bin Jiang Yingying Shan Xiaoli Wang Xi Lv Jihan Mohamed He Li Chunmei Wang Jianguang Chen Jinghui Sun 《Journal of separation science》2020,43(2):378-388
Schisandra chinensis lignans are the main active components of the traditional Chinese medicine Schisandra chinensis in East Asia. At present, there are more and more medicines and health foods in which the total S. chinensis lignans extracts are considered as the main active components, but little research has been done on the active components of S. chinensis lignans in the blood and main target organs. In this study, the components of S. chinensis lignans in the blood, liver and brain tissues of rats at different time points after the intragastrical administration of S. chinensis lignans were determined by a metabolomic method based on high‐performance liquid chromatography with quadrupole time‐of‐flight tandem mass spectrometry spectrometry. Twelve Schisandra chinensis lignans and 15 metabolites in the blood, liver, and brain of rats were identified. The results showed that the main metabolic ways of S. chinensis lignans in rats were hydroxylation, demethylation, and demethylation‐hydroxylation, and some of them might undergo demethylation, dehydrogenation, epoxidation, and elimination reaction. The time‐dose characteristics of S. chinensis lignans and their metabolites in the blood and target organs were analyzed, which may be helpful to elucidate the active substances that really exert the pharmacodynamic effects of S. chinensis lignans in organisms. 相似文献
69.
Xiao-shu Zhang Jia-qing Cao Guo-hui Shi Zhen-ting Liu Jing-xin Liu 《Natural product research》2016,30(3):358-361
Two new isoaurones derivatives were obtained from Callistephus chinensis flower. Their structures were elucidated on the basis of extensive spectroscopic analyses. Both of the new compounds were evaluated cytotoxic activity. Phytochemical investigation of Callistephus chinensis flower led to the isolation of two new isoaurones derivatives (Z)-4′,4,10-trihydroxy-siamaurone (1) and (E)-4′,4,10-trihydroxy-siamaurone (2). The structures of these new compounds were identified by the interpretation of spectroscopic data (mainly 1D and 2D NMR) and by comparison with data reported in the literature. Both of the new compounds were evaluated for their cytotoxicity. 相似文献
70.
GC-MS of volatile components of Schisandra chinensis obtained by supercritical fluid and conventional extraction 总被引:1,自引:0,他引:1
In this paper, the volatile compounds of Schisandra chinensis obtained by different extraction techniques including supercritical fluid extraction (SFE), steam distillation (SD), Soxhlet extraction (SE) and ultrasound-assisted extraction (UAE) were investigated for the first time. The sample preparation procedure for GC-MS analysis of the volatile compounds was optimized and then 37, 45, 27 and 37 compounds were identified in the samples obtained by SFE, SD, SE and UAE methods, respectively. As the therapeutic effect of the traditional Chinese medicine is usually based on multifarious essential components or the combination of them instead of only one component, the volatile compounds were compared in groups with the extracts by SE, SD and UAE. This would be more reasonable to evaluate the effects of an alternative technique to extracting multifarious essential components. Among the identified components in the SFE extract, 32 compounds were the same as that by three conventional methods, accounting for 90.5% of the volatile compounds identified. However, as the volatile compounds were classed into groups, it was easy to see that the Schisandra chinensis oil extracted by SFE was made up largely of aromatics and sesquiterpenoids (52.1 and 27.6%, respectively), with less amounts of monoterpenoids and other compounds, distinguishing SFE from the conventional extractions. 相似文献