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41.
From the press-residue of the fresh root tuber of Trichosanthes kirilowii Maim (Cucurbitaceae), a new ribosome-inactivating protein (RIP), trichobitacin, was isolated. It has the activity of RNA N-glycosidase and can inhibit the growth of human placental trophoblastic cells. Its molecular weight is 27,228 Da (ES-MS) and pI 9.6. It is a single chain basic RIP. Its amino acid composition was determined. It is a new RIP. It consists of 0.7~0.9% galactose and may be a glycoprotein. Its N- and C-terminal amino acid is Asp and Ala, respectively. Its N-terminal preliminary amino acid sequence has been determined.  相似文献   
42.
唇形科香茶菜属植物溪黄草(Rabdosia serra(Maxim·)Hara)具有清热祛湿、凉血散瘀、抗肿瘤、抗菌、消炎及对肝脏的保护作用[1,2]。据文献报道,溪黄草中的对映-贝壳杉烷型二萜化合物,是其具有抗癌作用的主要功效成分[3-5]。其结构与冬凌草甲素极为相似,在同一波长处具有相似的紫  相似文献   
43.
采用红外光谱的三级鉴定法分析鉴别了黄芪及其伪品刺果甘草。在一维红外光谱中,刺果甘草的1 737 cm-1CO伸缩振动峰,明显高于黄芪的1 737 cm-1特征峰,说明刺果甘草含有机酯类化合物的量相对高于黄芪。在高分辨的二阶导数谱中,刺果甘草有明显的1 620,1 317,782和516 cm-1的草酸钙特征峰,而黄芪没有。此外,两者都存在1 463,1 511和1 596 cm-1的芳香类化合物的特征峰,不同的是刺果甘草的1 468 cm-1峰的右侧还有一个1 453 cm-1的小肩峰。在二维相关红外光谱中,两者都存在1 070,1 095和1 140 cm-1的糖苷类化合物的自动峰,不同的是黄芪的1 140 cm-1的自动峰强度最大,但刺果甘草的1 090 cm-1自动峰强度最大。谱图的三级鉴定验证了黄芪及其伪品刺果甘草在糖苷类化合物、芳香类化合物和有机酯类化合物的相对含量上都是不一致的。该方法不仅可以快速有效地鉴别黄芪及其伪品刺果甘草,还提供了两者的有机酯类化合物以及芳香类和糖苷类化合物具有很大差别的一些有用的结构信息。因此,运用红外光谱法可以快速有效地分析和鉴定黄芪及其伪品刺果甘草。  相似文献   
44.
The essential oils of the flower-buds, leaves and stems of Filipendula palmata( Pall. ) Maxim. were analyzed by GC and GC-MS. Thirty-three, forty-seven and forty-seven compounds in the flower-buds, leaves and stems were identified, respectively. Methyl salicylate exists in a great amount which is up to 70. 10% in the flower-buds. Its amount is also high in other two parts. The data obtained show that it may be one of the main natural mosquito-expelling and pain-alleviating components in the three parts. The flower-buds are the main active part with the mosquito-expelling function.  相似文献   
45.
A simple and efficient method was developed for the simultaneous determination of eight isoquinoline alkaloids in methanol extracts of Dicranostigma leptopodum (Maxim) Fedde and the effective fractionation of the alkaloids of D. leptopodum by high‐performance liquid chromatography with diode array detection. The chromatographic conditions were optimized on a SinoChrom ODS‐BP column to obtain a good separation of the four types of alkaloid analytes, including two aporphines (isocorydine, corydine), two protopines (protopine and allocryptopine), a morphine (sinoacutine), and three quaternary protoberberine alkaloids (berberrubine, 5‐hydroxycoptisine, and berberine). The separation of these alkaloids was significantly affected by the composition of the mobile phase, and particularly by its pH value. Acetonitrile (A) and 0.2% phosphoric acid solution adjusted to pH 6.32 with triethylamine (B) were selected as the mobile phase with a gradient elution. With this method, a new quaternary protoberberine alkaloid was isolated and the two structural isomers (isocorydine and corydine) were baseline separated. The appropriate harvest period for D. leptopodum was also recommended based on our analysis. The method for the effective fraction of the alkaloids of D. leptopodum was optimized under this method with regard to the varying significant pharmacological activities of the alkaloids.  相似文献   
46.
Flavonoids are the main components of Meconopsis integrifolia (Maxim.) Franch, which is a traditional Tibetan medicine. However, traditional chromatography separation requires a large quantity of raw M. integrifolia and is very time consuming. Herein, we applied high‐speed counter‐current chromatography in the separation and purification of flavonoids from the ethanol extracts of M. integrifolia flower. Ethyl acetate/n‐butanol/water (2:3:5, v/v/v) was selected as the optimum solvent system to purify the four components, namely quercetin‐3‐O‐β‐d‐ glucopyrannosy‐(1→6)‐β‐d‐ glucopyranoside (compound 1 , 60 mg), quercetin 3‐O‐[2’’’‐O‐acetyl‐β‐d‐ glucopyranosyl‐(1→6)‐β‐d‐ glucopyranoside (compound 2 , 40 mg), quercetin 3‐O‐[3’’’‐O‐acetyl‐β‐d‐ glucopyranosyl‐(1→6)‐β‐d‐ glucopyranoside (compound 3 , 11 mg), and quercetin 3‐O‐[6’’’‐O‐acetyl‐β‐d‐ glucopyranosyl‐(1→6)‐β‐d‐ glucopyranoside (compound 4 , 16 mg). Among the four compounds, 3 and 4 were new acetylated flavonol diglucosides. After the high‐speed counter‐current chromatography separation, the purities of the four flavonol diglucosides were 98, 95, 90, and 92%, respectively. The structures of these compounds were identified by mass spectrometry and NMR spectroscopy.  相似文献   
47.
Two new benzoyl esters of glucose 1-O-(E)-4′-methoxybenzoyl-β-D-glucopyranose (1) and 1-O-(E)-4′-methoxybenzoyl-β-D-gluconic acid (2) were isolated from Lagotis yunnanensis, together with six previously known iridoid glucosides. The structures of these compounds were elucidated on the basis of spectral analysis, including 2D NMR spectroscopy. Published in Khimiya Prirodnykh Soedinenii, No. 6, pp. 529–530, November–December, 2006.  相似文献   
48.
Gao M  Wang L  Peng J  Xiao H 《色谱》2011,29(9):932-936
淫羊藿甙和朝藿定A、B、C是淫羊藿中重要的活性成分,本研究应用工业制备高效液相色谱从淫羊藿粗提物中分离制备了这4个成分。淫羊藿粗提物经大孔吸附树脂粗分离获得相应的组分后,利用工业制备高效液相色谱完成精制纯化。采用自装填Chromatorex C18制备柱(220 mm×77 mm, 10 μm),乙腈-水(26:74或30:70, v/v)为流动相进行洗脱,在35 min内,实现了这4种成分的基线分离及规模制备。从300 g粗提物(总黄酮含量约20%)中获得淫羊藿甙33 g、朝藿定C 4.6 g、朝藿定B 3.7 g和朝藿定A 0.6 g,产品纯度均达到98%以上。此方法通过两步分离即可实现这4种成分的完全分离,具有快速高效、产品纯度高的特点,适于淫羊藿中淫羊藿甙、朝藿定A、B、C系列对照品的规模制备。  相似文献   
49.
50.
Cynanchum auriculatum Royle ex Wight. (CA), Cynanchum bungei Decne. (CB) and Cynanchum wilfordii (Maxim.) Hemsl. (CW) are three close species belonging to the Asclepiadaceous family, and their dry roots as the bioactive part have been revealed to exhibit anti-tumor, neuroprotection, organ protection, reducing liver lipid and blood lipid, immunomodulatory, anti-inflammatory, and other activities. Until 2021, phytochemistry investigations have uncovered 232 compounds isolated from three species, which could be classified into C21-steroids, acetophenones, terpenoids, and alkaloids. In this review, the morphology characteristics, species identification, and the relationship of botany, extraction, and the separation of chemical constituents, along with the molecular mechanism and pharmacokinetics of bioactive constituents of three species, are summarized for the first time, and their phytochemistry, pharmacology, and clinical safety are also updated. Moreover, the direction and limitation of current research on three species is also discussed.  相似文献   
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