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1.
In order to study hybridisation, taxonomic boundaries and phylogeography in the genus Pseudopanax (Araliaceae), we developed seven novel microsatellite loci from enriched genomic libraries of P. lessonii and P. crassifolius. These loci were characterised in 16 individuals from a single population of P. crassifolius, and displayed 2–11 alleles per locus. Observed heterozygosities ranged from 0.063 to 0.688. Most loci were polymorphic in the closely related Pseudopanax species, and several loci amplified widely across the Araliaceae.  相似文献   
2.
A new triterpenoid saponin named bafouoside C 3-O-β-d-glucopyranosyl-(1  4)-[β-d-galactopyranosyl-(1  2)]-β-d-glucuronopyranosyloleanolic acid 28-O-β-d-glucopyranosyl ester; (1), together with five known compounds 3-O-β-d-galactopyranosyl-(1  2)-β-d-glucuronopyranosyloleanolic acid (2), 23-hydroxyursolic acid (3), 28-O-α-l-rhamnopyranosyl-(1  4)-O-β-d-glucopyranosyl-(1  6)-O-β-d-glucopyranosyl-23-hydroxyursolic acid (4), 3-O-β-d-glucopyranosyl-23-hydroxyursolic acid (5), and 3-O-α-l-arabinopyranosyl-23-hydroxyursolic acid (6), were isolated from the roots of Cussonia bancoensis Aubrev. & Pellegr. Their structures were established on the basis of 1D- and 2D NMR data, mass spectrometry and chemical methods. The NMR data of the known compounds, as far as we know, are herein reported for the first time in CD3OD. Compound 3 exhibited a weak cytotoxic activity against MDA-MB 231 human breast adenocarcinoma, A375 human malignant melanoma, and HCT116 human colon carcinoma cell lines.  相似文献   
3.
Traditional phylogenies based on analysis of multiple genes have failed to obtain a well‐resolved evolutionary history for the backbone of the Asian Palmate group of Araliaceae, the largest clade of the family. In this study, we applied the genome skimming approach of next‐generation sequencing to address whether the lack of resolution at the base of the Asian Palmate tree is due to molecular sampling error or the footprint of ancient radiation. Twenty‐nine complete plastid genomes of Araliaceae (17 newly sequenced) were analyzed (RAxML, Beast, Lagrange, and BioGeoBears) to provide the first phylogenomic reconstruction of the group (95% of genera included). As a result, the early divergences of the Asian Palmate group have been clarified but the backbone of its core is not totally resolved, with short internal branches pointing to an ancient radiation scenario. East Asia is inferred as the most likely ancestral area for the Asian Palmate group (from late Paleocene to Eocene) from which early colonization of the Neotropics is inferred during the Eocene. The radiation of the core Palmate group took place during the late Eocene, most likely in the context of the Boreotropical hypothesis. Recurrent episodes of southward migration (to the tropics) coupled with northern latitude local extinctions (promoting geographic isolation of lineages) followed by northward expansion (promoting contact of lineages that erased the trace of preceding geographic isolation) are hypothesized to have linked to the alternation of the cold and warm periods of the Eocene.  相似文献   
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5.
三七环二肽成分   总被引:15,自引:2,他引:13  
从三七(Panax notoginseng)的根中分离得到14个环二肽成分,通过波谱解析其结构分别鉴定为环-(亮氨酸-苏氨酸)(1)、环-(亮氨酸-异亮氨酸)(2)、环-(亮氨酸-缬氨酸)(3)、环-(异亮氨酸-缬氨酸)(4)、环-(亮氨酸-丝氨酸)(5)、环-(亮氨酸-酪氨酸)(6)、环-(缬氨酸-脯氨酸)(7)、环-(丙氨酸-脯氨酸)(8)、环-(苯丙氨酸-酪氨酸)(9)、环-(苯丙氨酸-丙氨酸)(10)、环-(苯丙氨酸-缬氨酸)(11)、环-(亮氨酸-丙氨酸)(12)、环-(异亮氨酸-丙氨酸)(13)、环-(缬氨酸-丙氨酸)(14)。其中化合物1为新化合物,化合物4~10为新天然化合物,化合物2~3、11~14为已知化合物;化合物2和11、3和4、12和13分别为一对混合物,比例分别为2:1、1:1和2:1。  相似文献   
6.
分子与形态证据表明湖南参 (HunaniopanaxhypoglaucusC .J.Qi&T .R .Cao)起源于木属 (AraliaL .) ,湖南参的近缘种为寄生五叶参 (Araliaparasitica)和轮伞五叶参 (Araliaverticillata) ,形态证据支持湖南参为轮伞五叶参的姐妹种 ,此 2种具轮伞花序这一共衍征。为了保证木属的单系性 ,现将湖南参并入木属 ,并作如下新组合 :Araliahypoglauca (C .J .Qi&T .R .Cao)J.Wen&Y .F .Deng .本文报道了湖南参在广西的新分布。目前的形态学和分子数据均不支持早先提出的湖南参与树参属 (Dendropanax)的近缘关系。本文亦报道了木属的 1新种、 2新种组合和 1个新名称 :AraliashangianaJ .Wen .sp .nov .(向氏五叶参 ,新种 ) ;Araliaglabrifoliolata (C .B .Shang)J .Wen .comb .nov . (光叶五叶参 ,新组合 ) ;Araliastellata (King)J.Wen ,comb .nov . (星毛羽叶参 ,新组合 )和AraliadelavayiJ .Wen .nom .nov .(云南五叶参 ,新名称 )。  相似文献   
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8.
Processive phytochemistry and pharmacological investigation of Schefflera leucantha R.Vig. (Araliaceae) led to the isolation of fifteen known compounds: a nucleobase (1), six small aromatic molecules (27), three phenylpropanoids (8–10), four lignans (1114) and a fatty acid derivative (15). Spectroscopic methods were used to establish the structure and configuration of isolates, followed by their unambiguous confirmation with literature data. We report for the first time (to the best of our knowledge), the isolation of β-amino-3-methoxy-4-hydroxybenzene-ethanol (4) from a natural source. Furthermore, compounds 1, 5, 915 are being reported from Araliaceae family for the first time, whereas compounds 2, 3, 68 from the genus Schefflera for the first time. The biological screening results show that compounds 9 and 10 induce a moderate inhibitory effect on aldose reductase, while compounds 3, 5, and 8 display significantly high neuroprotective activities.  相似文献   
9.
The allometry of axis length, diameter, and taper is described for the trunk, rachis, and rachilla of nonbranching ramets of Aralia spinosa. Significant log-linear relationships were found between length and diameter for all axis categories, and in all cases, scaling was negatively allometric. Linear models best described the relationship between length and diameter for the rachis and rachilla, while a quadratic model best described this relationship for the trunk. During the trunk-building stage, the safety factors for trunk height were size dependent, with larger trunks exceeding their predicted critical buckling height. Taper was described by a linear relationship between diameter and position along the axis for all axis categories. All rachises and rachillas sampled exhibited taper along the length of the axis, however, only 51% of the trunks showed continuous taper. The trunk was less tapered than the rachis, but no differences in taper were found between the trunk and the rachilla, or the rachis and the rachilla. In unbranched ramets the large bipinnately compound leaves occupy the space normally occupied by lateral branches. We suggest that the rachis and rachilla are functionally equivalent to branches, that is, acting as axes of exploration and exploitation of the environment.  相似文献   
10.
报道了寄生在人参(PanaxginsengMeyer)上的白粉菌属一新种:人参白粉菌(ErysiphepanacisR.L.Bai.etW.C.Liusp.nov.),此为白粉菌有性型在五加科(Arali aceae)植物上寄生的首次记载。模式标本存放在解放军农牧大学真菌标本室  相似文献   
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