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51.
SeonJu Park Yun Na Kim Hee Jae Kwak Eun Ju Jeong Seung Hyun Kim 《Bioorganic & medicinal chemistry letters》2018,28(4):552-557
Stilbenes have been reported to be phytoestrogen compounds owing to its structural similarity to the estrogenic agent diethylstilbestrol. To find new stilbene-derivative phytoestrogens, isolation of stilbene-rich R. undulatum was performed and led to identify six new compounds (1–5 and 28), one newly determined absolute configurations compound (27) together with 21 previously reported compounds (6–26). The structures of compounds were determined on the basis of extensive spectroscopic methods including 1D and 2D NMR and CD spectra data. All the isolated compounds were tested for their estrogenic activities in HepG2 cells transiently transfected with ERα, ERβ and ERE-reporter plasmid. Among them, stilbene-derivatives, piceatannol 3′-O-β-d-xylopyranoside (12), cis-rhaponticin (16) and rhapontigenin 3′-O-β-d-glucopyranoside (17), showed the more potent binding affinity for estrogen receptors than 17β-estrodiol. 相似文献
52.
Patrik Mráz 《Biologia》2006,61(1):115-120
Second part of commented chromosome number and DNA ploidy level reports from Central Europe comprising the whole Carpatho-Pannonian
region includes the data for following taxa: Tephroseris aurantiaca (2n = 96), T. capitata (2n = 64) and T. integrifolia (2n = 48) by J. Kochjarová from Poland and Slovakia (reports nos. 12–14); Urtica diocia and U. kioviensis (both 2n = 26) by M. Kolník & K. Goliašová from Slovakia (nos. 15–16); Viola hirta (2n = 20), V. odorata (2n = 20), V. reichenbachiana (2n = 20), V. riviniana (2n = 40, 2n ∼ 8x, based on x = 5), V. suavis (2n = 40) and V. × bavarica [V. reichenbachiana × v. riviniana] (2n ∼ 6x, based on x = 5) by P. Mereďa jun., I. Hodálová, P. Mártonfi & V. Kolarčík from Slovakia (nos. 17–22); Fallopia × bohemica [F. japonica × F. sachalinensis] (2n = 66), Thladiantha dubia (2n = 18) and Hieracium longifoliosum (2n = 36) by P. Mráz from Romania and Slovakia (nos. 23–25); Amsinckia calycina (2n = 34) by M. Perny & H. Šípošová from Slovakia (no. 26).
For further details and arrangements of reports see the first part (Mráz, 2005). 相似文献
53.
蓼科植物((Polygonaceae)具有重要的经济意义.其中有粮食作物,著名中药,蜜源植物,观赏植物以及其它经济植物.柄锈菌(Puccinia)是蓼科植物的重要的病原真菌.本文对我国寄生于蓼科植物的柄锈菌进行了分类研究. 在中国首先报告蓼科植物柄锈的是日本人三宅市郎(1914).我国真菌学家从30年代起分别描述或记载过各种蓼科植物的柄锈,并发表过一些中国特有的新种. 本文作者重新研究了中国科学院微生物研究所真菌标本室收藏的全部蓼科植物柄锈的标本以及近年来采集的未定名标本.共鉴定标本262号,得柄锈30种,包括5个新种:汶川柄锈(Pucinia wencuanensis),雾灵柄锈(P. wulingensis),南迩巴瓦柄锈(P.namjagbarwana),太白柄锈(P. taibaiana),掌叶大黄柄锈(P. rhei palmati),和五个国内新记录种:装饰柄锈(P, ornata),岩手山柄锈(P. iwateyamensis),山蓼柄锈(P. oxyriae),赫尔顿柄锈(P.hultenii),箭叶蓼柄锈(P.polygoni-sieboldii).寄主植物包括蓼科8属47种. 相似文献
54.
应用解剖镜和电子扫描显微镜对中国产蓼属萹蓄组Polygonum sect.Polygonum 16种1变种及1变型植物的果实形态进行了研究。发现该组5种一年生植物的果实具有两型性,即有长、短两种果实类型。短果类型为卵形,具三棱,包于宿存花被内或与花被近等长,呈黑褐色。在解剖镜下观察到其表面具小点、无光泽,而在电子扫描显微镜下观察到其表面具有散乱分布或排列成行的瘤状颗粒;长果类型为狭卵形,具三棱,长于宿存花被,黄褐色或淡黄绿色,在解剖镜下观察到其表面平滑、有光泽,而在电子扫描显微镜下观察到其表面上部具有散乱分布的瘤状颗粒,中、下部则具不规则洼点、星花状褶皱或浅波纹状。果实具两型性的植物有萹蓄P.aviculare、乌鲁木齐萹蓄P.urumqiense、展枝萹蓄P.patulum、直立萹蓄P.avicularef.erectum和尖果萹蓄P.rigidum。果实微形态可分为两种类型:1.果实表面无瘤状颗粒或疣状突起、有光泽,此类型又可以分为2种亚类型:(1)果实表面平滑、浅波纹状,如岩萹蓄P.cognatum、松叶萹蓄P.acerosum和帚萹蓄P.argyrocoleum;(2)果实表面具浅洼点或洼点,如铁马鞭P.plebeium和针叶萹蓄P.polycnemoides。2.果实表面有瘤状颗粒或疣状突起,无或具微光泽,此类型又可分为4种亚类型:(1)果实表面具疣状突起,如圆叶萹蓄P.intramongolicum.;(2)果实表面具散乱分布的瘤状颗粒,如普通萹蓄P.humifusum和展枝萹蓄的短果;(3)果实表面具有纵行排列的瘤状颗粒,如萹蓄和乌鲁木齐萹蓄的短果;(4)果实表面上部具散乱分布的瘤状颗粒,中、下部具不规则洼点、星花状褶皱或浅波纹状,如萹蓄、展枝萹蓄、直立萹蓄和尖果萹蓄的长果。因此果实两型性和果实微形态特征对蓼属萹蓄组种、变种的鉴定具有较大的分类学价值。基于果实微形态特征以及其他形态特征,确定了新种晖春萹蓄Polygonum huichunense F.Z.Li,Y.T.Hou&C.Y.Qu,同时恢复褐鞘萹蓄Polygonum aviculareL.var.fusco-ochreatum(Kom.)A.J.Li为原种,即Polygonum fusco-ochreatum Kom.。 相似文献
55.
The taxonomy of the Polygonum douglasii complex is revised. A summary of relevant taxonomic information is provided, along with a key to the species and subspecies,
plus typification, synonymy, discussion, distribution, and ecology. Morphology and micromorphology of stems, leaves, perianth,
pollen, and achenes are analyzed and illustrated. Based on these data, 12 species and two subspecies are recognized. A new
species, P. gabrielae, is described and illustrated from Oregon. 相似文献
56.
57.
Three new species in Polygonum section Polygonum (Polygonaceae) from Xinjiang, China, are described and illustrated. Polygonum urumqiense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. aviculare L. in habit, but differs by having flowers densely clustered and spicate in the upper part of branches, stamens 5–6, and two types of achenes (the longer one densely and irregularly granulate on surface). Polygonum tachengense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. aviculare in the flowers not forming a raceme in the upper part of branches, the stamens 8, and the achenes striate-granulate on surface, but differs by the leaf blades linear-lanceolate, the midvein and lateral veins conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, the flowers 3–6 clustered together in the upper axils of branches. This species is also similar to P. patulum M. Bieb. in the erect stem, and the flowers 3–6 clustered together in the axils of the upper part of branches, but differs by the midvein and lateral veins of leaves conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, the leaves in the upper part of branches not becoming smaller gradually, and the flowers clustered in the upper axils of branches not forming a raceme, and the achenes striate-granulate on surface. Polygonum shiheziense F. Z. Li, Y. T. Hou & F. J. Lu is similar to P. argyrocoleon Steud. ex Kunze in the erect stem, the 3–6 flowers clustered in the upper axils of branches, the stamens 8, and the slightly smooth achenes, but differs by the midvein and lateral veins of leaves conspicuously raising abaxially, the ochreae longer, up to 1.1 cm, 15–20-veined, and the flowers clustered in the upper axils of branches not forming a raceme. This species is also similar to P. tachengense in habit, but differs in the leaves borne in the upper part of branches becoming smaller gradually and the smooth, slightly shiny achenes. The pollen morphology, leaf epidermal characters and achene micromorphology of the three new species and their relatives were comparatively observed under the scanning electron microscope (SEM). 相似文献
58.
59.
《Saudi Journal of Biological Sciences》2022,29(3):1801-1807
Phytochemicals from plant extracts belong to an important source of natural products which have demonstrated excellent cytotoxic activities. However, plants of different origins exhibit diverse chemical composition and bioactivities. Therefore, discovery of plants based new anticancer agents from different parts of the world is always challenging. In this study, methanolic extracts of different parts of 11 plants from Saudi Arabia have been tested in vitro for their anticancer potential on human liver cancer cell line (HepG2). Particularly, for this study, plants from Asteraceae, Resedaceae and Polygonaceae families were chosen on the basis of locally available ethnobotanical data and their medicinal properties. Among 12 tested extract samples, three samples obtained from Artemisia monosperma stem, Ochradenus baccatus aerial parts and Pulicaria glutinosa stem have demonstrated interesting cytotoxic activities with a cell viability of 29.3%, 28.4% and 24.2%, respectively. Whereas, four plant extracts including Calendula arvensis aerial parts, Scorzonera musilii whole plant, A. monosperma leaves show moderate anticancer properties bearing a cell viability ranging from 11.9 to 16.7%. The remaining extracts have shown poor cytotoxic activities. Subsequently, GC-MS analysis of methanolic extracts of four most active plants extracts such as C. comosum, O. baccatus, P. glutinosa and A. monosperma detected the presence of 41 phytomolecules. Among which 3-(4-hydroxyphenyl) propionitrile (1), 8,11-octadecadiynoic acid methyl ester (2), 6,7-dimethoxycoumarin (3) and 1-(2-hydroxyphenyl) ethenone (4) were found to be the lead compounds of C. comosum, O. baccatus P. glutinosa and A. monosperma, respectively. 相似文献
60.