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1.
从广东蛇葡萄(Ampelopsis cantoniensis)藤茎的乙醇提取物的乙酸乙酯部分离得到13个化合物,经波谱技术鉴定为:白藜芦醇(1)、5,7-二羟基香豆素(2)、山奈酚(3)、二氢木犀草素(4)、槲皮素(5)、二氢槲皮素(6)、没食子酸(7)、杨梅素(8)、二氢杨梅素(9)、槲皮素-3-O-α-L-鼠李糖苷(10)、杨梅素-3-O-α-L-鼠李糖苷(11)、山奈酚-3-O-α-L-鼠李糖苷(12)、表儿茶素-3-O-没食子酸酯(13)。除化合物8和9,其余化合物均为首次从该植物中分离得到。  相似文献   

2.
利用色谱分离方法与现代波谱分析技术,对叶下珠乙酸乙酯提取物的化学成分进行了系统的研究。从中分离鉴定了14个黄酮类化合物,分别为槲皮素-3-(4"-O-乙酰基)-O-α-L-鼠李糖-7-O-α-L-鼠李糖苷(1)、槲皮素-7-O-α-L-鼠李糖苷(2)、槲皮素-3-O-α-L-鼠李糖苷(3)、槲皮素-3-O-β-D-葡萄糖苷(4)、芸香甙(5)、槲皮素(6)、山柰酚(7)、山柰酚-3-O-α-L-鼠李糖苷(8)、木犀草素(9)、木犀草素-7-O-β-D-葡萄糖苷(10)、蒙花苷(11)、山柰酚-3-O-β-芸香糖苷(12)、柚皮苷(13)、橙皮苷(14)。除5~7外的所有化合物均从该植物中首次分离。对分离所得的化合物进行了体外细胞毒和抗氧化活性测试,结果显示化合物6、9和10表现出一定的细胞毒活性,所有化合物均具有不同程度的抗氧化活性。  相似文献   

3.
采用硅胶色谱柱层析、聚酰胺色谱柱层析、制备薄层色谱及其它分离手段从香樟叶(Cinnamomum camphora Leaves)70%乙醇提取中分离得到9个化合物,根据化合物理化性质和波谱数据分别鉴定为:邻苯二甲酸二丁酯(1)、l-细辛脂素(2)、(8R,8'R)-3,3',4,4'-四甲氧基-9-氧代-8-8',9-O-9'-木脂素(3)、槲皮素-3-Ο-β-D-葡萄糖苷(4)、山奈酚-3-O-β-芸香糖苷(5)、山柰酚-3-O-α-L-吡喃鼠李糖苷(6)、槲皮素3-Ο-α-L-鼠李糖苷(7)、芦丁(8)、异鼠李素-3-O-β-芸香糖苷(9)。其中化合物1,2,6和9为首次从该种植物叶中分离得到。  相似文献   

4.
南山茶果皮化学成分的研究   总被引:1,自引:0,他引:1  
反复采用硅胶柱色谱法、Sephadex LH-20柱色谱法、ODS柱色谱法、反复重结晶等方法对南山茶果皮的化学成分进行分离纯化,并通过理化常数测定和波谱分析等方法进行结构鉴定。从南山茶果皮中分离并得到了10个化合物,分别鉴定为槲皮素(1)、山奈酚(2)、原儿茶酸(3)、山柰酚-3-O-β-D-葡萄糖基-(6→1)-2′′′,4′′′-O-二乙酰基-α-L-鼠李糖基-(3→1)-2′′′′,3′′′′,4′′′′-O-三乙酰基-α-L-鼠李糖苷(4)、山柰酚-3-O-β-D-葡萄糖基-(6→1)-4′′′-O-乙酰基-α-L-鼠李糖基-(3→1)-3′′′′-O-乙酰基-α-L-鼠李糖苷(5)、3-甲氧基鞣花酸(6)、鞣花酸(7)、羽扇豆烷醇(8)、β-谷甾醇(9)和胡萝卜苷(10)。化合物2、6、7均为首次从南山茶中分离得到,其中化合物6、7为首次从山茶属植物中分离得到。  相似文献   

5.
鬼针草黄酮类化学成分及其抗脂质过氧化作用的研究   总被引:9,自引:0,他引:9  
采用硅胶、Sephadex LH-20柱色谱等方法对鬼针草乙醇提取物的乙酸乙酯萃取部分进行化学成分研究,并利用IR,1H NMR,13C NMR,MS等光谱技术鉴定其化学结构.从鬼针草中分离得到了6个黄酮类化合物,经鉴定分别为:5-羟基-6,7-二甲氧基黄酮(1)、山奈酚-7-O-α-L-鼠李糖苷(2),槲皮素-7-O-葡萄糖苷(3)、槲皮素-3-O-α-L-鼠李糖苷(4),5,7,3‘,4‘-四羟基-3-甲氧基黄酮(5)和β-谷甾醇(6).这些化合物均为首次从该植物中分得.另外,针对分离得到的化合物进行测定小鼠血清MDA水平,SOD和GSH-Px活性,研究发现化合物2,3,4和5具有较强的抗脂质过氧化作用.  相似文献   

6.
罗汉果化学成分的研究   总被引:4,自引:0,他引:4  
用硅胶柱层析、制备薄层层析和Sephadex LH-20柱层析等方法对罗汉果[Siraitia grosvenorii(Swingle)C.Jeffrey]75%乙醇提取物化学成分进行分析,共分离得到8个化合物,通过质谱法和核磁共振波谱法及理化性质鉴定为:罗汉果醇苯甲酸酯(1)、厚朴酚(2)、双[5-甲酰基糠基]醚(3)、5-羟甲基糠酸(4)、山柰酚-7-O-α-L-鼠李糖苷(5)、山柰酚-3,7-O-α-L-二鼠李糖苷(6)、山柰酚(7)、琥珀酸(8).除化合物1、6和7外,其余均为首次从该植物中分离得到.  相似文献   

7.
研究罗汉果(Siraitia grosvenorii)水提果渣的化学成分及其体外抗炎活性。采用多种色谱方法对罗汉果果渣化学成分进行系统的分离纯化,得到了26个化合物,并结合MS、NMR等波谱学手段对其进行结构鉴定,分别为齐墩果酸28-O-β-D-吡喃葡萄糖苷(1)、齐墩果酸3-O-β-D-吡喃葡萄糖醛酸苷-6′-乙酯(2)、(3α)-3,29-dihydroxy-7-oxomultiflor-8-ene-3,29-diyl dibenzoate(3)、3,29-二苯甲酰基栝楼仁二醇(4)、isomultiflorenol(5)、curcasinlignan B(6)、urolignoside(7)、diospyrosin(8)、楝叶吴萸素B(9)、4′-羟基苯基乙基香草酸酯(10)、橙黄胡椒酰胺乙酸酯(11)、山柰酚-7-O-α-L-鼠李糖苷(12)、山柰苷(13)、山柰酚-3-O-β-D-吡喃葡萄糖基-7-O-α-L-鼠李糖苷(14)、山柰酚-3-O-α-L-鼠李糖苷-7-O-β-D-木糖苷(1→2)-O-α-L-鼠李糖苷(15)、sagittatin A(16)、葫芦烷-5,24-二烯-3β-醇(17)、balsaminol E(18)、大豆脑苷I(19)、β-谷甾醇(20)、β-胡萝卜苷(21)、胆甾-5-烯-3β,7α-二醇(22)、2 E-4-羟基-壬烯酸(23)、香兰素(24)、对羟基苯乙醇(25)、β-hydroxypropiovanillone(26)。化合物2、6~11为首次在葫芦科植物中分离得到,化合物1、3、4、14~16、18、19、22~26为首次从罗汉果属植物中分离得到。初步研究了化合物1~26的体外抗炎活性,化合物4、5、7、13、19和21能抑制TNF-α生成,化合物13和21能同时抑制IL-1β、IL-6的生成,化合物7、19、22能抑制IL-1β的生成,化合物5能抑制IL-6的生成。  相似文献   

8.
小花棘豆化学成分的研究   总被引:6,自引:0,他引:6  
从有毒植物小花棘豆(Oxytropis glabra DC.)的地上部分分离得到10种化合物,经光谱分析及理化常数测定,分别鉴定为槲皮素(Ⅰ)、山奈酚(Ⅱ)、3′,7-二羟基-2′,4′-二甲氧基-异黄烷(Ⅲ)、山奈-7-O-α-L-鼠李吡喃糖甙(Ⅳ)、山奈酚-3-O-β-D-葡萄吡喃糖甙(Ⅴ)、山奈酚--O-β-D-葡萄吡喃糖(1→2)-β-D-葡萄吡喃糖甙(Ⅵ)、山奈酚-3-O-β-D-葡萄吡喃糖-7-O-β-D-葡萄吡喃糖甙(Ⅶ)槲皮素-3-O-β-D-葡萄吡喃糖甙(Ⅷ)、杨梅树皮甙(Ⅺ)和3-O-[α-L-鼠李吡喃糖基(1→3)-β-D-葡萄吡喃糖基(1→6)-β-D-葡萄吡喃糖醛酸基]-黄豆醇B(Ⅹ)。上述成分均为首次从该植物中分得。化合物Ⅹ为新化合物。  相似文献   

9.
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   

10.
采用硅胶柱层析、Sephadex LH-20凝胶、制备液相等方法从连花清瘟胶囊原料药中分离得到17个化合物。通过IR、MS、1H NMR、13C NMR等波谱手段鉴定为(+)-松脂素(1)、连翘苷(2)、表松脂素-4'-O-β-D-葡萄糖苷(3)、罗汉松脂素-4'-O-β-D-葡萄糖苷(4)、大黄酚-1-O-β-D-葡萄糖苷(5)、芦荟大黄素-8-O-β-D-葡萄糖苷(6)、大黄酚(7)、大黄素(8)、大黄素甲醚(9)、芦荟大黄素(10)、芦荟大黄素乙酸酯(11)、槲皮素-3-O-α-L-鼠李糖苷(12)、山柰酚-3-O-α-L-鼠李糖苷(13)、五福花苷酸(14)、没食子酸(15)、苯甲酸(16)和β-谷甾醇(17)。本研究首次通过系统化学分离、鉴定手段从连花清瘟胶囊原料药中分离、鉴定17个化合物,为阐明连花清瘟胶囊的化学物质基础提供了重要的科学研究数据。  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.
13.
Parsimony analyses of the internal transcribed spacer regions of nuclear ribosomal DNA (ITS 1 & ITS 2) for 38 taxa sampled from the Phebalium group (Rutaceae: Boronieae) and two outgroups confirm that, with the exception of Phebalium sensu stricto and Rhadinothamnus, six of the currently recognised genera within the group are monophyletic. The data indicate that Phebaliums. str. is paraphyletic with respect to Microcybe, and Rhadinothamnus is paraphyletic with respect to Chorilaena. Rhadinothamnus and Chorilaena together are the sister group to Nematolepis. Drummondita, included as an outgroup taxon, clustered within the ingroup as sister to Muiriantha and related to Asterolasia.The phylogeny suggests that the evolution of major clades within a number of these genera (e.g. Phebalium) relates to vicariance events between eastern and south-western Australia. Leionema is an eastern genus, with the most basal taxon being the morphologically distinct Leionema ellipticum from northern Queensland. Leionema also includes one species from New Zealand, but this species (as with some others) proved difficult to sequence and its phylogenetic position remains unknown. Taxonomic changes at the generic level are recommended.The authors wish to thank Paul G.Wilson, PERTH, for advice and discussion, and Paul Forster, BRI, for collecting and providing material of Leionema ellipticum. The project was supported by a Melbourne University Postgraduate Award (to BM), the Australian Biological Resources Study (ABRS), Australian Systematic Botany Society and Wolf Den (Australia) Investments.  相似文献   

14.
Some closely related members of the monocotyledonous familiesAlismataceae, Liliaceae, Juncaceae, Cyperaceae, Poaceae andAraceae with variable modes of pollination (insect- and wind-pollination) were studied in relation to the ultrastructure of pollenkitt and exine (amount, consistency and distribution of pollenkitt on the surface of pollen grains). The character syndromes of pollen cementing in entomophilous, anemophilous and intermediate (ambophilous or amphiphilous) monocotyledons are the same in principal as in dicotyledons. Comparing present with former results one can summarize: 1) The pollenkitt is always produced in the same manner by the anther tapetum in all angiosperm sub-classes. 2) The variable stickiness of entomophilous and anemophilous pollen always depends on the particular distribution and consistency of the pollenkitt, but not its amount on the pollen surface. 3) The mostly dry and powdery pollen of anemophilous plants always contains a variable amount of inactive pollenkitt in its exine cavities. 4) A step-by step change of the pollen cementing syndrome can be observed from entomophily towards anemophily. 5) From the omnipresence of pollenkitt in all wind-pollinated angiosperms studied one can conclude that the ancestors of anemophilous angiosperms probably have been zoophilous (i.e. entomophilous) throughout.
  相似文献   

15.
seventeen new species and combinations are proposed in the generaChondrorhyncha, Cischweinfia, Cochlioda, Eloyella, Encyclia, Kefersteinia, Koellensteinia, Macroclinium, Rodriguezia, Solenidiopsis, andStenia. All new species are illustrated. A key is provided for 2-flowered species ofMacroclinium, PeruvianSigmatostalix, and PeruvianStenia. Solenidium (Solenidiopsis) peruvianum Schltr. is lectotypified.  相似文献   

16.
郭英兰 《菌物学报》1991,10(Z1):119-128
本文报导作者采自安徽枯牛降自然保护区的18种丝孢菌,分属于5个属,其中有3个新种:牛皮冻生尾孢(Cercospora paederiicola),山鸡椒假尾饱(Pseudocercospora litseae-cubebae),鸡血藤生假尾孢(P. millettiicola)和2个中国新纪录。文中对新种进行了描述及绘图,新记录种作了简要说明。研究的标本保存在中国科学院微生物研究所真菌标本室(HMAS)。  相似文献   

17.
Little is known about how tropical land-use systems contribute to the conservation of functionally important insect groups, including dung beetles. In a study at the margin of Lore Lindu National Park (a biodiversity hotspot in Central Sulawesi, Indonesia) dung-beetle communities were sampled in natural forest, young secondary forest, agroforestry systems (cacao plantations with shade trees) and annual cultures (maize fields), each with four replicates (n = 16 sites). At each site we used 10 pitfall traps, baited with cattle dung, along a 100 m transect for six 3-day periods. The number of trapped specimens and species richness at the natural forest sites was higher than in all land-use systems, which did not significantly differ. Each land-use system contained, on average, 75% of the species richness of the natural forest, thereby indicating their importance for conservation. However, a two-dimensional scaling plot based on NESS indices (m = 6) indicated distinct dung beetle communities for both forest types, while agroforestry systems and annual cultures exhibited a pronounced overlap. Mean body size of dung beetles was not significantly influenced by land-use intensity. Five of the six most abundant dung beetle species were recorded in all habitats, whereas the abundance of five other species was significantly related to habitat type. Mean local abundance and number of occupied sites were closely correlated, further indicating little habitat specialisation. The low dung beetle diversity (total of 18 recorded species) may be due to the absence of larger mammals in Sulawesi during historical times, even though Sulawesi is the largest island of Wallacea. In conclusion, the dung beetle fauna of the lower montane forest zone in Central Sulawesi appears to be relatively robust to man-made habitat changes and the majority of species did not exhibit strong habitat preferences.  相似文献   

18.
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   

19.
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.
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20.
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