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排序方式: 共有94条查询结果,搜索用时 15 毫秒
21.
Peng-Yu Zhuang Ming-Hua Chen Ya-Nan Wang Ya-Jing Feng Dan-yang Zhang 《Natural product research》2018,32(20):2468-2475
One new sesqui-neolignan compound, namely, sesqui-illisimonan A (1), one new neolignan, illisimonan A (2), and one new phenylpropanoid compound, illisimoid A (3) were isolated from the fruits of Illicium simonsii Maxim. The structures and absolute configurations of these compounds were determined by extensive spectroscopic, including NMR, circular dichroism and calculated electronic circular dichroism methods. The antioxidant activities of compounds 1–3 were also evaluated. Vitamin E was selected as the positive control (IC50 = 49.73 ± 0.88 μM). Compounds 1 and 2 exhibited in vitro antioxidant activity with an IC50 value of 55.76 ± 1.30 and 59.36 ± 0.50 μM, respectively. However, the compound 3 didn’t show obvious antioxidant activity. 相似文献
22.
藏药短穗兔耳草化学成分的研究 总被引:8,自引:0,他引:8
从短穗兔耳草(Lagotis brachystachya Maxim)的全草中分离出一种新的黄酮甙,经光谱和化学方法确定为[3,5-二羟基-3′,5′-二甲氧基-7-O-葡萄糖甙],定名为兔耳草甙(2)(Lagotiside),还分离鉴定了6种已知化合物。 相似文献
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石香薷中两个新黄酮甙的研究 总被引:4,自引:0,他引:4
石香薷中两个新黄酮甙的研究郑尚珍,孙丽萍,沈序维王毅(西北师范大学化学系,兰州,730070)(中国科学院兰州化学物理研究所)关键词石香薷,唇形科,黄酮甙唇形科植物石香薷(MOslachinensisMaxim)作为中药,用来治疗暑湿感冒、头痛、腹痛... 相似文献
26.
Three new sesquiterpenes,namely schensianol A(1),schensianolside A(2) and schensianolside B(3) were isolated from the stems and leaves of Euonymus schensianus Maxim.Their structures were established by chemical methods and spectroscopic techniques including 2D NMR. 相似文献
27.
中草药溪黄草低极性组份的研究 总被引:1,自引:0,他引:1
1前言溪黄草(Rabdosia.serra(Maxim.)Hara)属于唇形科香茶菜属植物,是一种多年生草本植物。据中华大辞典记载,其具有清热祛湿,凉血散瘀之功效,对急性肝炎,肠炎,痢疾等有较好效果。但是该植物化学组成的研究目前在国外尚未有报道,国内研究报道有4篇卜’1。共分出8个化合物:RabdoserrinA,RabdoserrinB,BxclsanlnA,Kamebakaunn,Za一羟基乌索酸,乌索酸,卜谷自醇及一p谷尚醇一D一葡萄糖贰。该植物的石油醚提取层的化学组分未见报道。我们利用高… 相似文献
28.
The cause of liver damage by using black cohosh preparation has been concerned but remains unclear. After a preliminary investigation, the black cohosh medicinal materials sold in the market were adulterated with Asian cohosh (Cimicifuga) without removing the fibrous roots. The safety of Cimicifuga rhizome and fibrous roots is unknown and has not been reported. Therefore, in this paper, the rhizome and fibrous roots of Cimicifuga dahurica (Turcz.) Maxim (C. dahurica) were completely separated, extracted with 70% ethanol, and freeze-dried to obtain crude rhizome extract (RC) and fibrous roots extract (FRC). UHPLC-Q-TOF-MS was used to identify 39 compounds in the rhizome and fibrous roots of Cimicifuga, mainly saponins and phenolic acids. In the L-02 cytotoxicity experiment, the IC50 of fibrous roots (1.26 mg/mL) was slightly lower than that of rhizomes (1.417 mg/mL). In the 90-day sub-chronic toxicity study, the FRC group significantly increased the level of white blood cells, ALP, ALT, AST, BILI and CHOL (p < 0.05); large area of granular degeneration and balloon degeneration occurred in liver tissue; and the expression of p-NF-kB in the nucleus increased in a dose-dependent manner. Overall, Fibrous roots of Cimicifuga are at risk of hepatotoxicity and should be strictly controlled and removed during the processing. 相似文献
29.
青海地道中藏药材山莨菪人工引种栽培试验成功。采集两年生和三年生种植山莨菪在不同生长期的植物全植株,采用流动注射氢化法原子吸收光谱分别测试了其不同组织中铅、砷、汞、镉等重金属元素含量。结果表明,山莨菪在生长周期内吸收的重金属元素并非全部蓄积在根组织器官中,部分重金属元素通过年生长周期内的生长发育而随着地上茎叶部分等组织器官的枯萎被代谢排出植物体外。 相似文献
30.