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1.
蓝桉果实中的脂溶性成分   总被引:2,自引:0,他引:2  
从蓝桉(Eucalyptus globulusLabill.)果实乙醇提取物的石油醚部位分离鉴定出6个化合物,通过理化和波谱分析结构鉴定为:5-羟基-4′,7-二甲氧基-6-甲基黄酮(1)、blumenol A(2)、蓝桉醇(3)、绿花白千层醇(4)、β-谷甾醇(5)、二十二烷酸(6),其中化合物1~4和化合物6系首次从该植物中分离得到,化合物1和2首次从桉属植物中分离得到.  相似文献   

2.
运用硅胶和凝胶色谱等天然产物分离技术从红背山麻杆根中分离得到9个化合物,结合各化合物理化性质和光谱数据鉴定其结构,包括6个三萜类成分鲨烯(1)、乙酰基木油醇酸(2)、木栓酮(3)、3-乙酰氧基-12-齐墩果烯-28-酸甲酯(4)、马斯里酸(5)、马斯里酸甲酯(6)和3个甾醇成分β-谷甾醇(7)、β-谷甾醇-3-O-硬脂酸酯(8)、豆甾-4-烯-3,6-二酮(9)。化合物2、3和7为首次从该植物中分离得到,其余化合物均为首次从该属植物中分离得到。以体外酶学方法测定化合物PTP1B抑制活性,化合物2、5、6和8具有PTP1B抑制活性。  相似文献   

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为探讨小叶米仔兰(Aglaia odorata var.microphyllina)中的抗菌活性成分,从其枝条的乙醇提取物中分离得到6个化合物,通过波谱分析,分别鉴定为:4(15)-桉叶烯-1β,7,11-三醇(1)、4α,10β,11-三羟基-1,5-反-愈创木烷-6-烯(2)、6,15α-环氧-1β,4β-二羟基桉烷(3)、2-羟基-丁二酸-1-甲酯(4)、巴西红厚壳素(5)和胡萝卜苷(6)。以上化合物均为首次从该植物中分离得到,其中化合物1、2、4和5为首次从米仔兰属植物中分离得到。用滤纸片琼脂扩散法测定了化合物1~5的抗菌活性,结果显示化合物4和5对金黄色葡萄球菌有抑制作用。  相似文献   

4.
吴颖瑞  赵友兴  周俊 《广西植物》2010,30(6):884-886
从山龙眼属植物潞西山龙眼的叶子中分离了6个化合物,利用核磁共振等方法,鉴定为熊果苷(1)、ro-bustaside B(2)、robustaside D(3)、β-谷甾醇(4)、helicide(5)和(E)-(4-羟基苯基)-丙烯酸甲酯(6)。这6个化合物均为首次从该植物中分离得到。  相似文献   

5.
本文采用现代色谱分离手段从嗜低温真菌Pseudogymnoascus pannorum的大米发酵产物中分离得到8个化合物,采用现代波谱技术鉴定其结构,分别为:L-pyroglutamyl-L-phenylalanine(1)、(R)-N-acetylphenylalanine(2)、(R)-Nacetyltryptophan (3)、methyl 2-hydroxy-4-(3-hydroxy-5-methylphenoxy)-6-methylbenzoate (4)、2-hydroxy-4-(2-hydroxy-3-methoxy-5-methylphenoxyl)-6-methylbenzoate(5)、vanillic acid(6)、1,3,5-三甲氧基苯(7)和亚油酸(8)。其中化合物1和2为首次从天然界分离得到,化合物3~8为首次从假裸囊菌属真菌中分离得到。化合物1~8对人肝癌细胞Hep G-2和人乳腺癌细胞MCF-7未显示细胞毒作用。  相似文献   

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为了解三叶木通[Akebia trifoliata(Thunb.)Koidaz]的化学成分,从其茎的乙醇提取物中分离得到7个苯丙素类化合物。经过光谱分析,分别鉴定为osmanthuside E(1)、木通苯乙醇苷B(2)、2-(4-hydroxyphenyl)ethyl-(6-O-feruloyl)-β-D-glucopyranoside(3)、dunalianoside D(4)、dunalianoside C(5)、咖啡酸(6)、秦皮乙素(7)。除化合物6外,其他化合物均为首次从该植物中分离获得,化合物4和5为首次从木通属植物中分离得到。  相似文献   

7.
采用色谱法从黑果枸杞中分离得到7个化合物,借助波谱学方法鉴定了它们的结构,分别鉴定为2-O-(3-甲氧基4,5-二羟基苯甲酰基)-4-羟基-6-O-β-D-吡喃葡萄糖基苯乙酸(1)、绿原酸(2)、绿原酸甲酯(3)、glucoacetosyringone(4)、丁香酸(5)、对羟基苯甲醛(6)和3,4-二羟基-5-甲氧基苯甲酸甲酯(7)。其中化合物1为新化合物,化合物4和7为首次从本属中被分离得到。  相似文献   

8.
从北美盐角草中分离得到6个化合物,运用波谱手段分别鉴定为东莨菪内酯(1),杜松脑(2),金丝桃苷(3),槲皮素(4),异鼠李素-3-O-β-D-葡萄糖苷(5)和β-谷甾醇(6)。其中,化合物1和2为该属植物中首次分离得到,化合物4和6为首次从该种植物中得到。  相似文献   

9.
肾蕨的化学成分研究   总被引:2,自引:0,他引:2  
从肾蕨乙醇提取物中分离得到6个化合物,根据理化和光谱分析,鉴定为β-谷甾醇(1)、羊齿-9(11)-烯(2)、齐墩果酸(3)、肉豆蔻酸十八烷基酯(4)、正三十一烷酸(5)和正三十烷醇(6),化合物3~6为首次从该植物中分离得到。  相似文献   

10.
从珍珠菜(Lysimachia clethroidesDuby)的70%丙酮提取物中分离得到11个化合物,经理化性质及波谱数据分析分别鉴定为23-羟基乌苏酸(1)、Isotachioside(2)、对羟基苯甲酸(3)、3-甲氧基-4-羟基苯甲酸(4)、原儿茶酸(5)、3,5-二羟基苯甲酸(6)、甲基-α-D-呋喃果糖苷(7)、尿苷(8)、β-谷甾醇(9)、胡萝卜苷(10)和齐墩果酸(11)。化合物1、2、4、7和8为首次从该属植物中分离得到,化合物3、5、6、9~11为首次从该种植物中分离得到。  相似文献   

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It has now been over twenty years since a novel herpesviral genome was identified in Kaposi's sarcoma biopsies. Since then, the cumulative research effort by molecular biologists, virologists, clinicians, and epidemiologists alike has led to the extensive characterization of this tumor virus, Kaposi's sarcoma-associated herpesvirus(KSHV; also known as human herpesvirus 8(HHV-8)), and its associated diseases. Here we review the current knowledge of KSHV biology and pathogenesis, with a particular emphasis on new and exciting advances in the field of epigenetics. We also discuss the development and practicality of various cell culture and animal model systems to study KSHV replication and pathogenesis.  相似文献   

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Comprises species occurring mostly in subtidal habitats in tropical, subtropical and warm-temperate areas of the world. An analysis of the type species, V. spiralis (Sonder) Lamouroux ex J. Agardh, a species from Australia, establishes basic characters for distinguishing species in the genus. These characters are (1) branching patterns of thalli, (2) flat blades that may be spiralled on their axis, (3) width of the blade, (4) primary or secondary derivation of sterile and fertile branchlets and (5) position of sterile and fertile branchlets on the thalli. Application of the latter two characters provides an important basic method for separation of species into three major groups. Osmundaria , a genus known only in southern Australia, was studied in relation to Vidalia , and its separation from the Vidalia assemblage is not accepted. Species of Vidalia therefore are transferred to the older genus name, Osmundaria. Two new species, Osmundaria papenfussii and Osmundaria oliveae are described from Natal. Confusion in the usage of the epithet, Vidalia fimbriala Brown ex Turner has been clarified, and Vidalia gregaria Falkenberg, described as an epiphyte on Osmundaria pro/ifera Lamouroux, is revealed to be young branches of the host, Osmundaria prolifera.  相似文献   

18.
Fifteen chromosome counts of six Artemisia taxa and one species of each of the genera Brachanthemum, Hippolytia, Kaschgaria, Lepidolopsis and Turaniphytum are reported from Kazakhstan. Three of them are new reports, two are not consistent with previous counts and the remainder are confirmations of very scarce (one to four) earlier records. All the populations studied have the same basic chromosome number, x = 9, with ploidy levels ranging from 2x to 6x. Some correlations between ploidy level, morphological characters and distribution are noted.  相似文献   

19.
肝癌中HBV和HCV基因和抗原的分布及意义   总被引:1,自引:0,他引:1  
采用原位分子杂交方法检测HCV RNA及HBV X基因;采用免疫组织化学方法研究HCV核心抗原,非结构区C33c抗原及HBxAg在肝细胞肝癌中的定位及分布.结果表明(1)HCV RNA、HBV X基因在肝细胞肝癌组织检出率分别为40%(55/136)和82%(112/136).HCV RNA定位于癌细胞的胞浆内,阳性细胞呈散在、灶状及弥漫分布三种形式;HBV X基因在肝癌细胞中的分布呈胞浆型、核型及核浆型,阳性细胞也呈上述三种分布形式;(2)HCV C33c抗原、核心抗原在肝细胞肝癌中的阳性率为81%(133/164)及86%(141/164).C33c抗原定位于癌细胞及肝细胞的胞浆内;核心抗原既定位于癌细胞核中,又可定位于胞浆中.C33c抗原阳性细胞以灶状分布为主;而核心抗原阳性细  相似文献   

20.
For a plant selection model with frequency-independent viabilities, fertilities and selfing rates, it is shown that apart from global fixation, for certain parameter combinations a protected polymorphism and facultative fixation (either allele may become fixed according to initial frequencies) may both occur. Facultative fixation requires different selling rates for the dominant and recessive type. Protection of the polymorphism requires resource allocation for male and female function. In this connection the problem of purely genetically caused population extinction is discussed.
For general frequency dependence and regular segregation, the chances for establishment of a completely recessive gene are compared to those of a completely dominant gene. It is proven that the process of establishment of the recessive gene, despite a fitness advantage, may be considerably endangered by drift effects if random mating prevails. The recessive gene may reach the same effectivity in establishment as a dominant gene, only if the recessive homozygote mates exclusively with its own type during the period of establishment.  相似文献   

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