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1.
In the course of our study of bioactive natural products from Schisandra plants, we isolated a neolignan from an EtOAc extract of the stems of Schisandra propinqua (Wall.) Baill. The structure of the new com- pound was determined to be 4, 4-di (4-hydroxy-3-methoxyphenly)-2, 3-dimethylbutanol (compound 1) on the basis of 1H- and 13C-NMR spectra and 2D NMR methods. Eight known compounds, compounds 2-9, were also isolated and identified, of which compounds 3, 4, 6 and 9 were isolated for the first time from this plant. In addition, compounds 1-4 were evaluated for cytotoxicity by an 3-(4,5-dimethyl-2 thiazoyl)-2,5-diphenyl-2H- tetrazolium bromide (MTT) assay. Compound 1 showed significant potential cytotoxic ability in the bioassay.  相似文献   
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A petroleum ether extract of Kadsura longipedunculata enhanced the GABA-induced chloride current (IGABA) by 122.5 ± 0.3% (n = 2) when tested at 100 μg/ml in Xenopuslaevis oocytes expressing GABA A receptors (α1β2γ2S subtype) in two-microelectrode voltage clamp measurements. Thirteen compounds were subsequently identified by HPLC-based activity profiling as responsible for GABA A receptor activity and purified in preparative scale. 6-Cinnamoyl-6,7-dihydro-7-myrceneol and 5,6-dihydrocuparenic acid were thereby isolated for the first time. The determination of the absolute stereochemistry of these compounds was achieved by comparison of experimental and calculated ECD spectra. All but one of the 13 isolated compounds from K. longipedunculata potentiated IGABA through GABA A receptors composed of α1β2γ2S subunits in a concentration-dependent manner. Potencies ranged from 12.8 ± 3.1 to 135.6 ± 85.7 μM, and efficiencies ranged from 129.7 ± 36.8% to 885.8 ± 291.2%. The phytochemical profiles of petroleum ether extracts of Kadsura japonica fruits (114.1 ± 2.6% potentiation of IGABA at 100 μg/ml, n = 2), and Schisandra chinensis fruits (inactive at 100 μg/ml) were compared by HPLC-PDA-ESIMS with that of K. longipedunculata.  相似文献   
4.
五味子科的系统发育:核糖体DNA ITS区序列证据   总被引:13,自引:0,他引:13  
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5.
国产五味子科五种植物叶片脉序研究   总被引:4,自引:0,他引:4  
首次报道了国产五味子科5种植物的叶脉特征,对科、属、种的特征作了描述,编排有分种检索表.通过与八角科叶脉的比较,支持建立五味子科与八角科的观点,认为五味子属的系统位置在南五味子属之后,并讨论了八角目的演化趋势  相似文献   
6.
五味子科的系统发育:核糖体DNA ITS区序列证据   总被引:3,自引:0,他引:3  
The Schisandraceae is one of the most important taxa for understanding the origin and evolution of primitive angiosperms due to its basal position in the recent cladograms of the angiosperm based both on several gene sequences and on morphological characters, but phylogenetic relationships within the family are still unresolved. The sequences of nrDNA ITS region of 15 species representing four sections of Schisandra Michx., two sections of Kadsura Kaempf. ex Juss. and one outgroup, Illicium fargesii Finet et Gagnep., were used to reconstruct the phylogeny of Schisandraceae. Fourteen most parsimonious trees (Length=259, CI=0.934 and RI=0.889) were obtained from the analysis with I.fargesii as the outgroup. In the consensus tree, the genus Schisandra was found to be divided into three clades. Sect. Pleiostema formed a clade together with sect. Maximowiczia, sect. Sphaerostema was weakly supported to be the sister group of a clade comprising S. bicolor var. tuberculata and Kadsura species. In particular, S. bicolor var. tuberculata, a species of sect. Schisandra, was nested within Kadsura. It seems from this result and the morphological characters that Schisandra might not be a monophyletic group. According to the present molecular phylogeny, both elongated hypocarpium and deciduous habit originated independently at least twice in the Schisandraceae, and therefore, the value of the present morphological characters used in the classification of the family Schisandraceae should be reevaluated.  相似文献   
7.
林祁 《植物研究》2006,26(1):53-57
孙成仁在2002年《植物分类学报》第40卷第2期“五味子科植物种子表面微形态及其系统学意义”一文中对林祁(2000)所做的五味子科分类学修订提出了不同的看法。本文对此作出解答,认为由于双方在实验材料、实验方法、实验结果、植物分类学研究方法等方面存在差异,从而得出不同的研究结论。  相似文献   
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国产五味子科植物导管分子的比较解剖   总被引:11,自引:3,他引:8  
对五味子科 2属 1 9种植物导管分子的结构进行了比较观察。结果表明 :2属均以具缘纹孔导管为主 ,少有梯纹和螺纹导管 ,南五味子属多数种还有梯孔纹导管 ;2属导管长度和宽度差异很小 ,长 /宽比值有差异 ;根据穿孔板的结构可分为 2种形式 :( 1 )单穿孔板 ,这类穿孔板较普遍存在 ;( 2 )梯形穿孔板 ,发现 2属中的红花五味子 (Schisandrarubriflora)、五味子 (S .chinensis)、翼梗五味子 (S .henryi)、铁箍散 (S .propinquavar.sinensis)和黑老虎 (Kadsuracoccinea) 5种植物的导管分子具有此类穿孔板。其中五味子属中的五味子导管分子只具有梯形穿孔板 ,无单穿孔板 ,但横条较少 ,多为 2~ 3条。  相似文献   
9.
五味子科植物的木脂素成分   总被引:14,自引:0,他引:14  
五味子科植物分为五味子属 ( Schisandra)和南五味子属 ( Kadsura) 2个属 ,其中五味子 ( S.chinensis)为著名中药 ,其应用已有 2 0 0 0多年的历史 ,一直为我国药典所收载 ,该科其它许多种也在民间广泛应用 [1 ]。 2 0世纪 70年代初 ,我国临床研究中发现五味子能明显降低肝炎患者血清谷丙转氨酶水平 ,引起广泛研究的热潮 ,并由此开发出治疗肝炎药物联苯双酯 [2 ] 。迄今 ,国内外已对二十余种五味子科植物进行了研究 ,分离鉴定出大约 2 0 0个成分 ,其中 1 50多个为木脂素。五味子科木脂素结构类型多 ,立体化学复杂 ,而且生物活性广泛。除了…  相似文献   
10.
HPLC and TLC profiling was carried out for leaf and fruit extracts of five Schisandraceae species: Schisandra chinensis, S. rubriflora, S. spehenanthera, S. henryi and Kadsura japonica. HPLC measurements confirmed presence of lignans and phenolic compounds in fruits and leaves of all tested species. The most abundant in lignans was S. chinensis fruit extract in which 15 compounds were detected (e. g.: schisandrol A, schisanhenol, γ-schisandrin, gomisin N). The effect-directed detection, i. e., TLC-direct bioautography against Bacillus subtilis, showed exceptionally high activity for S. chinensis and S. rubriflora fruit extracts. On the other hand, TLC-DB enzyme tests (α-glucosidase, lipase, tyrosinase and acetylcholinesterase (AChE) inhibition assays) showed that all fruit and leaf extracts have ability to inhibit the above-mentioned enzymes (except for the K. japonica fruit). The leaf extracts showed much stronger antioxidant activity than the fruit ones, which were assessed and compared using both TLC-direct bioautography and spectrophotometric measurements based on ABTS, DPPH and FRAP tests.  相似文献   
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