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1.
白花蛇舌草的化学成分研究   总被引:14,自引:0,他引:14  
从白花蛇舌草(Hedyotis diffusaWilld)的全草中分离得到12个化合物,应用波谱学方法鉴定为p-香豆酸(p-coumaric acid,1)、阿魏酸(ferulic acid,2)、齐墩果酸(oleanolic acid,3)、熊果酸(ursolic acid,4)、2-甲基-3-羟基-蒽醌(2-methyl-3-hydroxyanthraquinone,5)、2-甲基-3-甲氧基蒽醌(2-methyl-3-methoxyanthraqui-none,6)、东莨菪内酯(scopolin,7)、槲皮素(quercetin,8)、山奈酚(kaeperferol,9)、胡萝卜苷(daucosterol,10)、豆甾醇(stigmasterol,11)和β-谷甾醇(-βsitosterol,12)。化合物2、7为首次从该植物中分得。  相似文献   

2.
蔓生百部的化学成分研究   总被引:2,自引:0,他引:2  
从蔓生百部(Stemona japonica)根中分离得到13个化合物,通过波谱数据,它们鉴定为β-谷甾醇(1)、豆甾醇(2)、5,11-豆甾二烯-3β-醇(3)、苯甲酸(4)、4-甲氧基苯甲酸(5)、1,8-二羟基-3-甲基蒽醌(6)、1,8-二羟基-6-甲氧基-3-甲基蒽醌(7)、氧代狭叶百部碱(8)、百部定碱(9)、异狭叶百部碱(10)、绿原酸(11)、栀子苷(12)和藏红花素A(13).所有化合物均为首次从该植物中分离得到.  相似文献   

3.
应用多种色谱技术进行分离纯化,从刺五加果肉水提取物中分离得到10个化合物,经理化性质和波谱分析鉴定其结构分别为左旋芝麻脂素(1)、紫丁香树脂酚(2)、6,7-二甲氧基香豆素(3)、7-羟基-6-甲氧基香豆素(4)、儿茶酚(5)、芦丁(6)、12-羟基硬脂酸(7)、豆甾醇(8)、β-谷甾醇(9)和蔗糖(10)。化合物3、4、5、7和8为首次从该植物中分得,其中化合物7为新的天然产物。  相似文献   

4.
为了研究元宝草(Hypericum sampsonii Hance)全草的化学成分,利用硅胶柱层析、Sephadex LH-20等色谱技术对元宝草三氯甲烷部位进行分离和纯化,共得到6个化合物,通过1H NMR、13C NMR、HMQC、HMBC等波谱技术分别鉴定为2,6-二羟基-4,3’,5’-三甲氧基二苯甲酮(1)、1,3,6-三羟基-2-甲基蒽醌(2)、山奈酚(3)、木犀草素(4)、3,4-二羟基苯甲酸乙酯(5)、β-谷甾醇(6),其中化合物1为新化合物,化合物2和5首次从该植物中分离得到。  相似文献   

5.
黄桐树皮的化学成分研究   总被引:1,自引:0,他引:1  
从黄桐(Endospermum chinense Benth.)树皮中分离获得了10个化合物。通过光谱分析,分别鉴定为3-羰基齐墩果酸(1)、齐墩果酸(2)、7-羰基谷甾醇(3)、β-谷甾醇(4)、β-胡萝卜甙(5)、7-羰基-β-胡萝卜甙(6)、4-羟基-3-甲氧基苯甲醛(7)、7-羟基-6-甲氧基香豆素(8)、3-羟基-4-甲氧基苯甲酸(9)和壬二酸(10)。10个化合物均为首次从黄桐树皮中分离得到。  相似文献   

6.
柴胡红景天化学成分的研究   总被引:2,自引:0,他引:2  
董礼  李磊  廖志华  陈敏  孙敏 《西北植物学报》2007,27(12):2564-2567
采用正相与反相硅胶柱色谱和薄层色谱分离纯化的方法,从景天科红景天属植物柴胡红景天(Rhodiola bupleuroides)根茎70%乙醇提取物的乙酸乙酯萃取部分中分离得到7个化合物,用光谱分析(UV,IR,MS,1H-NMR,13C-NMR)和化学反应鉴定化合物分别为:没食子酸(1)、山奈酚-7-O-α-L-吡喃鼠李糖苷(2)、草质素-7-O(3″-O-β-D-葡萄糖基)-α-L鼠李糖苷(3)、槲皮素(4)、丁香酸(5)、3,5-二甲氧基-4-羟基-苯甲酸-7-O-β-D-葡萄糖苷(6)、β-谷甾醇(7).以上化合物均为首次从该植物中分离得到,其中化合物5和6为首次从红景天属植物中发现.  相似文献   

7.
利用多种层析方法,从白头树(Garuga forrestii)树枝95%的乙醇提取物中分离得到10个化合物,通过理化性质和波谱分析,分别鉴定为13α,14β,17α-羊毛甾-7,24-二烯-1β,3β-二醇(1)、豆甾-5-烯-3β,7α-二醇(2)、豆甾-5-烯-3β,7β-二醇(3)、豆甾-3β,6α-二醇(4)、β-谷甾醇(5)、儿茶素(6)、(Z)阿魏酸二十四烷基酯(7)、(E)阿魏酸二十四烷基酯(8)、4-羟基-3-甲氧基苯甲酸(9)和1-甲氧基2,3苯并环戊烷(10).这些化合物均为该种植物首次报道.  相似文献   

8.
采用硅胶柱层析结合制备液相从巴戟天(Morinda officinalis)中分离得到8个蒽醌类化合物。根据化合物的波谱数据并与文献对照进行了结构鉴定,分别为2-羟甲基-3-羟基蒽醌(2-hydroxymethyl-3-hydroxyanthraquinone,1)、3-羟基-2-羟甲基-1-甲氧基蒽醌(3-hydroxy-2-hydroxymethyl-1-methoxyanthraquinone,2)、2-羟基-1-甲氧基蒽醌(2-hydroxy-1-methoxyanthraquinone,3)、3-羟基-1,2-二甲氧基蒽醌(3-hydroxy-1,2-dimethoxyanthraquinone,4)、甲基异茜草素-1-甲醚(rubiadin-1-methyl ether,5)、1,3-二羟基-2-甲氧基蒽醌(1,3-dihydroxy-2-methoxyanthraquinone,6)、1,3-二羟基-2-乙氧甲基蒽醌(ibericin,7)、1,2-二羟基-3-甲基蒽醌(1,2-dihydroxy-3-methylanthraquinone,8)。其中蒽醌(2)为首次从该植物中分得。利用MTT法对分离出的蒽醌的体外抗癌活性进行筛选,结果显示蒽醌(3)、(5)和(7)对肝癌细胞SMMC-7721增殖有明显的抑制作用,当蒽醌的浓度为400μmol/L时,蒽醌(3)、(5)和(7)对肝癌细胞的抑制率分别为44. 63%、20. 52%、54. 89%。  相似文献   

9.
镰形棘豆化学成分的研究   总被引:1,自引:0,他引:1  
采用柱层析(CC)、短柱减压层析、重结晶等分离手段,从镰形棘豆乙醇提取液中分得7个已知化合物,经波谱分析鉴定为N-苯甲酰基-2-苯基乙胺(1),N-肉桂酰基-2-苯基-2-乙胺(2),N-苯甲酰基-2-羟基-2-苯基乙胺(3),2′-羟基-4′-甲氧基查儿酮(4),7-甲氧基黄烷酮(5)、5-羟基-7-甲氧基黄烷酮(6),β-谷甾醇(7).化合物1~3、5、6均为首次从该植物中分到.药理实验表明化合物4,5对人胃癌细胞株SGC有较强的细胞毒活性,IC50分别为3.61和6.11 μg/mL.  相似文献   

10.
竹叶兰化学成分的研究   总被引:1,自引:0,他引:1  
从竹叶兰(Arundina graminifolia) 90%乙醇提取物中利用MCI、硅胶、大孔树脂通过柱色谱技术分离得到8个化合物,经波谱分析鉴定为4-(4-羟苄基)-3,4,5-三甲氧基环己-2,5-二烯酮(1)、apigenin 6,8-di-C-β-glucopyranoside (vicenin-2,2)、7-羟基-2,4-二甲氧基-9,10-二氢菲(orchinol,3)、7-羟基-2-甲氧基菲-1,4-二酮(densiflorol B,4)、1-(4-羟基-3,5-二甲氧基苯基)丙烷-1-酮(5)、正二十四饱和脂肪酸甘油酯-1(6)、β-谷甾醇(7)、胡萝卜苷(8),化合物1为新化合物,化合物2、5和6为首次从该植物中得到.  相似文献   

11.
Scirtothrips perseae Nakahara was discovered attacking avocados in California, USA, in 1996. Host plant surveys in California indicated that S. perseae has a highly restricted host range with larvae being found only on avocados, while adults were collected from 11 different plant species. As part of a management program for this pest, a “classical” biological control program was initiated and foreign exploration was conducted to delineate the home range of S. perseae, to survey for associated natural enemies and inventory other species of phytophagous thrips on avocados grown in Mexico, Guatemala, Costa Rica, the Dominican Republic, Trinidad, and Brazil. Foreign exploration efforts indicate that S. perseae occurs on avocados grown at high altitudes (>1500 m) from Uruapan in Mexico south to areas around Guatemala City in Guatemala. In Costa Rica, S. perseae is replaced by an undescribed congener as the dominant phytophagous thrips on avocados grown at high altitudes (>1300 m). No species of Scirtothrips were found on avocados in the Dominican Republic, Trinidad, or Brazil. In total, 2136 phytophagous thrips were collected and identified, representing over 47 identified species from at least 19 genera. The significance of these species records is discussed. Of collected material 4% were potential thrips biological control agents. Natural enemies were dominated by six genera of predatory thrips (Aeolothrips, Aleurodothrips, Franklinothrips, Leptothrips, Scolothrips, and Karnyothrips). One genus each of parasitoid (Ceranisus) and predatory mite (Balaustium) were found. Based on the results of our sampling techniques, prospects for the importation of thrips natural enemies for use in a “classical” biological control program in California against S. perseae are not promising.  相似文献   

12.
Komárek has recently reviewed the various species assigned to the green algal genusNeochloris Starr (Chlorococcales, Chlorococcaceae) and removed those with uninucleate vegetative cells to a new genus,Ettlia. Watanabe & Floyd, unaware ofKomárek's work, also reviewed the species ofNeochloris and distributed them among three genera—Neochloris, Chlorococcopsis gen. nov., andParietochloris gen. nov.—on the basis of details of the covering of the zoospore and the arrangement of the basal bodies of the flagellar apparatus. This paper reconciles these two treatments and makes additional recommendations at the ranks of genus, family, order, and class.  相似文献   

13.
The cardinalfishes (Apogonidae) are a diverse clade of small, mostly reef-dwelling fishes, for which a variety of morphological data have not yielded a consistent phylogeny. We use DNA sequence to hypothesize phylogenetic relationships within Apogonidae and among apogonids and other acanthomorph families, to examine patterns of evolution including the distribution of a visceral bioluminescence system. In conformance with previous studies, Apogonidae is placed in a clade with Pempheridae, Kurtidae, Leiognathidae, and Gobioidei. The apogonid genus Pseudamia is recovered outside the remainder of the family, not as sister to the superficially similar genus Gymnapogon. Species sampled from the Caribbean and Western Atlantic (Phaeoptyx, Astrapogon, and some Apogon species) form a clade, as do the larger-bodied Glossamia and Cheilodipterus. Incidence of visceral bioluminescence is found scattered throughout the phylogeny, independently for each group in which it is present. Examination of the fine structure of the visceral bioluminescence system through histology shows that light organs exhibit a range of morphologies, with some composed of complex masses of tubules (Siphamia, Pempheris, Parapriacanthus) and others lacking tubules but containing chambers formed by folds of the visceral epithelium (Acropoma, Archamia, Jaydia, and Rhabdamia). Light organs in Siphamia, Acropoma, Pempheris and Parapriacanthus are distinct from but connected to the gut; those in Archamia, Jaydia, and Rhabdamia are simply portions of the intestinal tract, and are little differentiated from the surrounding tissues. The presence or absence of symbiotic luminescent bacteria does not correlate with light organ structure; the tubular light organs of Siphamia and chambered tubes of Acropoma house bacteria, those in Pempheridae and the other Apogonidae do not.  相似文献   

14.
The genusKarschia, in the earlier sense, including saprophytes and parasites on lichens, has been thought to be a non-lichenized parallel genus of the lichen genusBuellia. Modern workers included it on the one hand inBuellia, on the other hand combined it with bitunicate ascomycetes. It is now proved thatKarschia is heterogeneous and contains but superficially similar members both of the genusBuellia of theLecanorales and of typical or masked bitunicateAscomycetes. Therefore, it can not be regarded as a link betweenLecanorales andDothideales. The type species ofKarschia belongs to theDothideales.
  相似文献   

15.
Since 1999, four specific weevils (Coleoptera, Curculionidae) were released in the Republic of Congo against three exotic floating water weeds: Neochetina eichhorniae Warner and N. bruchi Hustache against water hyacinth, Neohydronomus affinis Hustache against water lettuce, and Cyrtobagous salviniae Calder and Sands against water fern. Recoveries of exotic weevils were made from all 24 release sites except one, and all four species have established and spread (up to 800 km for water hyacinth weevils). Within a few years of releases, control of water fern and water lettuce was such that fishing and navigation could be resumed, while reductions of water hyacinth populations were only beginning.  相似文献   

16.
A molecular phylogeny of Hebeloma species from Europe   总被引:2,自引:1,他引:1  
In order to widen the scope of existing phylogenies of the ectomycorrhizal agaric genus Hebeloma a total of 53 new rDNA ITS sequences from that genus was generated, augmented by sequences retrieved from GenBank, and analysed using Bayesian, strict consensus and neighbour joining methods. The lignicolous Hebelomina neerlandica, Gymnopilus penetrans, and two species of Galerina served as outgroup taxa. Anamika indica, as well as representatives of the genera Hymenogaster and Naucoria, were included to test the monophyly of Hebeloma, which is confirmed by the results. Hebeloma, Naucoria, Hymenogaster and Anamika indica cluster in a strongly supported monophyletic hebelomatoid clade. All trees largely reflect the current infrageneric classification within Hebeloma, and divide the genus into mostly well-supported monophyletic groups surrounding H. crustuliniforme, H. velutipes, H. sacchariolens, H. sinapizans, and H. radicosum, with H. sarcophyllum being shown at an independent position; however this is not well supported. The section Indusiata divides with strong support into three groups, the position of the pleurocystidiate Hebeloma cistophilum suggests the possible existence of a third subsection within sect. Indusiata. Subsection Sacchariolentia is raised to the rank of section.  相似文献   

17.
18.
Systematic significance of mature embryo of bamboos   总被引:1,自引:0,他引:1  
The mature embryo of seven species belonging to five genera of Indian bamboos is described. In all these the basic pattern of embryo organisation is same: the scutellar and coleoptilar bundles are not separated by an internode, the epiblast is absent, the lower portion of the scutellum and the coleorhiza are separated by a cleft and the margins of embryonic leaves overlap. The features unique to fleshy fruited bamboos are: presence of a massive scutellum, the juxtaposition of plumule and radicle and the occurrence of a bud in the axil of the coleoptile. The fleshy fruit bearing bamboos should be classified into one group, the tribeMelocanneae. Evidence is provided to recognise additional groups in the subfamilyBambusoideae.  相似文献   

19.
Synopsis In a fourteen month study (May 1976 – June 1977) I examined the following characteristics of an intertidal bay goby (Lepidogobius lepidus) in Morro Bay, California, U.S.A.: annual and seasonal patterns of abundance, age composition and growth rates, survivorship and mortality patterns, and the reproductive cycle for female gobies. Fishes were collected with the aid of quinaldine and otoliths and ovaries removed. Age and growth rates were estimated from otolith annuli using a back calculation formula and a Brody-Bertalanffy growth curve. Mortality rates were derived using the methods of Heincke (1913), Robson & Chapman (1960), mean age, and a catch curve (Ricker 1975). A gonad index was used to describe the annual reproductive cycle. Results indicated that abundance fluctuated seasonally and that these fluctuations appeared to be caused by reproductive emigrations. Bay gobies reached an age of 7+ and a standard length of 87 mm. Growth was relatively constant (6 mm yr−1) until age 5, at which point it began to decline. The mean rates of survivorship, mortality, and instantaneous mortality were 0.75, 0.25, and 0.29 respectively. Mortality rates for individual age classes ranged from 0.13 to 0.51 and increased with age. This stock appears to reproduce mainly during the winter.  相似文献   

20.
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