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1.
红树林植物木果楝细胞毒活性和化学成分研究   总被引:2,自引:0,他引:2  
本研究采用MTT法对红树林植物木果楝(Xylocarpus grantum)正己烷提取物进行细胞毒活性筛选,结果显示对宫颈癌Hela细胞有较强的生长抑制活性。为了确定其中的活性成分,利用GC/MS法对正己烷提取物的化学成分进行分析,共鉴定了17种成分,大部分为有机酸类化合物。其中油酸(Oleic acid,24.89%)、棕榈酸(Palmitic acid,24.82%)和亚油酸(Linoleic acid,16.86%)为主要成分,据文献报道亚油酸具有肺腺癌细胞生长抑制活性。  相似文献   
2.
The fatty acid, sterol and hydrocarbon compositions of the fresh leaves from eleven species of mangroves, cultivated in a shadehouse, are reported. The fatty acid and sterol analyses, whilst generally typical of higher plants, showed several chemotaxonomically significant differences between the species. The epicuticular wax hydrocarbons and fatty acids were low in abundance compared to previous reports of mangrove leaf lipids, which may reflect the importance of environmental influences on this group of compounds. Cluster analysis of selected subsets of the data showed clear chemotaxonomic divisions amongst the mangroves. The results grouped the mangroves into genera, except for the Rhizophora and Ceriops tagal which were not separated, and grouped the family Rhizophoraceae distinct from all other species except Xylocarpus granatum. Avicennia marina var. resinifera was able to be distinguished from Avicennia marina by cluster analysis, supporting its assignment as a distinct variety. The results show that the lipids of mangroves are chemotaxonomically significant.  相似文献   
3.
A new andirobin, thaimoluccensin A (1), and two new phragmalin-type limonoids, thaimoluccensins B (2) and C (3), were isolated from seeds of a Thai mangrove plant, Xylocarpus moluccensis, together with eight known compounds. The structures of these compounds were elucidated on the basis of spectroscopic data. Only 7-deacetylgedunin (7), a gedunin-type limonoid, exhibited significant inhibitory activity against nitric oxide production from activated macrophages with IC50 value less than 10 μM, suggesting that the compound has anti-inflammatory activity.  相似文献   
4.
Ten limonoids, named godavarins A-J (1-7, 9-11), were isolated from seeds of an Indian mangrove (Xylocarpus moluccensis) collected in the mangrove wetlands of Godavari estuary, Andhra Pradesh. Eight known limonoids, viz. xyloccensins L (8), P (12), Q (13), mexicanolide (14), 6-deoxy-3-detigloyl-swietenine acetate (15), fissinolide (16), methyl 3β-acetoxy-1-oxomeliaca-8(30),14-dienoate (17), and methyl 3β-acetoxy-1-oxomeliaca-8(9),14-dienoate (18), were also obtained. The structures of these compounds were established on the basis of spectroscopic data or comparison with data in the literature (known compounds). The stereostructure of godavarin D was confirmed by means of single-crystal X-ray analysis. Godavarins A-C are the first mexicanolide derivatives with a C7-C28 ester-linked δ-lactone ring, while godavarins D-G are further additions to the small group of limonoids with a C1-C29 oxygen bridge. Godavarin H is a phragmalin with five acetoxy groups. Two limonoids, mexicanolide and fissinolide, were found to exhibit marked antifeedant activity against the third-instar larvae of Brontispa longissima (Gestro) at a concentration of 0.5 mg/mL. The most potent compound was mexicanolide. It also showed moderate insecticidal activity.  相似文献   
5.
Eight new species in seven new genera of follicular fruits are described from the Late Cretaceous of southern Sweden. They are Agapitocarpus emisxus , Chontrocarpus pachytoichus , Maiandrocarpus moirasmenus , Malliocarpus batrachoides , Mitocarpus elegans , Xylocarpus rhitidoides , Zeugarocarpus adroagathus and Z. leptoagathus . The fossil follicles are borne along infructescence axes or more commonly occur as isolated, dispersed fruits. Three genera, Maiandrocarpus , Mitocarpus and Zeugarocarpus , have follicles in distinct pairs borne spirally on an infructescence axis. Each follicle of a pair faces the axis with its ventral slit, which strongly indicates that the paired follicles were derived from two separate, monocarpellate flowers rather than from a single, bicarpellate flower. One genus ( Malliocarpus ) has follicles borne individually in the infructescence and three others ( Agapitocarpus , Chontrocarpus and Xylocarpus ) are known only as dispersed follicles. The paired follicles share many features with most of the dispersed follicles, including a sessile stigmatic area, a three-layered simple follicle wall, a simple vascular system composed of one dorsal and two lateral bundles, as well as a marginal-linear placentation bearing several anatropous ovules. Accordingly they are thought to belong to the same complex of taxa. The general structure of the fossils and comparison with modern angiosperms suggest that the fossils might represent an extinct lineage within or close to basal eudicots and many characters are shared with members of extant Proteaceae.  © 2005 The Linnean Society of London, Botanical Journal of the Linnean Society , 2005, 148 , 377–407.  相似文献   
6.
7.
Ten limonoids, named granatumins L–U ( 1 – 10 , resp.), were isolated from the seeds of an Indian mangrove, Xylocarpus granatum, collected in the estuary of Krishna, Andhra Pradesh. The structures of these compounds were established on the basis of spectroscopic data. The relative configuration of granatumin L ( 1 ) was confirmed by a single‐crystal X‐ray diffraction analysis. Granatumins L–T ( 1 – 9 , resp.) belong to the small group of limonoids with an oxygen bridge between C(1) and C(29), while granatumin U ( 10 ) is a 28‐Me‐oxidized mexicanolide. This is the first report of limonoids with an O‐bridge between C(1) and C(29) from the Indian X. granatum. The pronounced structural diversity of limonoids from this mangrove might originate from environmental factors.  相似文献   
8.
9.
Cell-free extracts of petioles of Arctium lappa catalyzed enantioselective formation of (+)-secoisolariciresinol [about 20% enantiomer excess (e.e.)] from achiral coniferyl alcohol in the presence of NADPH and H2O2. This is the first report of an enzymatic reaction to afford (+)-secoisolariciresinol enantioselectively.  相似文献   
10.
Two new mexicanolides, named granatumins H and I ( 1 and 2 , resp.), and two phragmalins, named granatumins J and K ( 3 and 4 , resp.), were isolated from the seeds of an Indian mangrove, Xylocarpus moluccensis, collected from the swamps of Krishna estuary, Andhra Pradesh. The structures of these limonoids were established on the basis of spectroscopic data. Granatumin J ( 3 ) is a highly oxidized phragmalin with five AcO groups, whereas granatumin K ( 4 ) is the first phragmalin found in nature with conjugated C(8)?C(30) and C(14)?C(15) bonds.  相似文献   
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