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1.
荫生鼠尾草植物中的三萜类化学成分研究   总被引:3,自引:2,他引:1  
刘青  刘珍伶  田瑄 《西北植物学报》2007,27(6):1141-1146
从采自陕西省太白山的唇形科(Labiatae)鼠尾草属(Salvia Linn.)植物荫生鼠尾草(Salvia umbratica Hance)丙酮提取物中分离得到14个五环三萜类化合物,并用现代波谱技术(MS、1H NMR、13C NMR、DEPT)和化学方法进行结构鉴定.结果显示:14个化合物分别为β-香树脂醇(1)、α-香树脂醇(2)、2α,3α-二羟基齐墩果-12-烯-28-酸(3)、3-氧-乌苏-12-烯-28-酸(4)、2α,3β-二羟基齐墩果-12-烯-28-酸(5)、3β,19-二羟基齐墩果-12-烯-28-酸(6)、齐墩果酸(7)、2α,3β-二羟基乌苏-12-烯-28-酸(8)、3β-羟基-11α-甲氧基-齐墩果-12-烯(9)、3β-羟基-11α-甲氧基-乌苏-12-烯(10)、3β,11α-二羟基-齐墩果-12-烯(11)、3β,11α-二羟基-乌苏-12-烯(12)、乌苏酸(13)、3β-羟基齐墩果-10,12-二烯(14).实验结果表明五环三萜类化合物是该植物中的主要成分.  相似文献   

2.
硬孔灵芝的化学成分研究   总被引:5,自引:0,他引:5  
采用硅胶柱层析法进行分离纯化,从硬孔灵芝Ganoderma duropora的氯仿萃取物中分离得到甾类化合物8种。根据波谱数据,化合物1-8结构分别被鉴定为:麦角甾醇、麦角甾-7,22-二烯-3β-醇、麦角甾-7,22-二烯-3-酮、6,9-环氧麦角甾-7,22-二烯-3β-醇、过氧麦角甾醇、3,5-二羟基麦角甾-7,22-二烯-6-酮、β-谷甾醇和胡萝卜苷。  相似文献   

3.
运用硅胶柱、反相硅胶柱、凝胶柱、HPLC和薄层制备等色谱技术及重结晶从白木香内生真菌Botryosphaeria rhodina A13的固体发酵产物中分离纯化了10个化学成分,通过化合物波谱数据及理化性质鉴定它们的结构分别为豆甾-4-烯-3-酮(1)、豆甾-5-烯-3β-醇-7-酮(2)、豆甾-4-烯-3,6-二酮(3)、(22E,24S)-5α,6α-环氧基-24-甲基胆甾-8(14),22-二烯-3β,7α-二醇(4)、5,4'-二羟-7-甲氧基黄酮(5)、香草酸(6)、对甲氧基苯甲酸(7)、尿嘧啶(8)、2-甲氧基对苯二酚(9)、2-甲基-3,5-羟基色酮(10)。其中化合物1~10均为首次从该属真菌中分离得到,化合物4具有细胞毒活性。  相似文献   

4.
该文采用ODS、硅胶、Sephadex LH-20等柱色谱技术,对柬埔寨野生柯拉斯那沉香(Aquilaria crassna)进行了研究。结果表明:从柬埔寨柯拉斯那所产沉香的乙醇提取物中进行分离共得到了10个化合物,包括一对对映异构体(9a/9b)。经波谱解析分别鉴定为6-甲氧基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(1)、6-甲氧基-2-[2-(3-甲氧基-4-羟基苯)乙基]色酮(2)、6,7-二甲氧基-2-(2-苯乙基)色酮(3)、6-羟基-2-(2-苯乙基)色酮(4)、6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(5)、8-氯-6-羟基-2-[2-(3-羟基-4-甲氧基苯)乙基]色酮(6)、8-氯-6-羟基-2-[2-(4-甲氧基苯)乙基]色酮(7)、oxidoagarochromone B(8)、4'-demethoxyaqusisnenone D(9)。其中,化合物6、7和9均为首次从柯拉斯那沉香中分离得到。活性测试结果显示,化合物1和2对乙酰胆碱脂酶具有一定的抑制活性,化合物2对人慢性髓原白血病细胞K562具有较弱的抑制作用。  相似文献   

5.
运用硅胶、凝胶和高效液相色谱进行分离纯化,根据理化常数和波谱数据鉴定化合物的结构。从中药枳壳中分离并鉴定了7个环肽成分:环-(亮氨酸1-异亮氨酸2-丙氨酸3-苏氨酸4-甘氨酸5-苏氨酸6-苯丙氨酸7)(1)、环-(甘氨酸1-亮氨酸2-缬氨酸3-亮氨酸4-脯氨酸5-丝氨酸6)(2)、环-(亮氨酸1-亮氨酸2-脯氨酸3-酪氨酸4-甘氨酸5-丝氨酸6-脯氨酸7)(3)、环-(甘氨酸1-甘氨酸2-亮氨酸3-亮氨酸4-亮氨酸5-脯氨酸6-脯氨酸7-苯丙氨酸8)(4)、环-(脯氨酸-丙氨酸)(5)、环-(丙氨酸-异亮氨酸)(6)、环-(丙氨酸-亮氨酸)(7)。除2和4外,其余环肽均为首次从中药枳壳中分离得到。  相似文献   

6.
为了解薏苡(Coixlachryma-jobi)糠壳的化学成分,利用多种柱色谱技术对其乙醇提取物乙酸乙酯萃取部位进行分离,经波谱数据分析鉴定了15个化合物,分别为香豆酸(1)、香豆酸甲酯(2)、2-羟乙基-香豆酸酯(3)、咖啡酸甲酯(4)、阿魏酸甲酯(5)、(E)-3-(4-甲氧基苯基)丙烯酸(6)、2,3-二羟基-1-(4-羟基-3-甲氧基苯基)-1-丙酮(7)、2,3-二羟基-1-(4-羟基-3,5-二甲氧基苯基)-1-丙酮(8)、对羟基苯甲酸(9)、3-羟基-4-甲氧基苯甲酸(10)、1,3,5-三甲氧基苯(11)、methyl (3-hydroxy-2-oxo-2,3-dihydroindol-3-yl)-acetate (12)、尿囊素(13)、2-(2-羟乙基)-3-甲基反丁烯二酸(14)和油酸(15),其中化合物3、7、12、13和14为首次从薏苡中分离得到。活性测试结果表明,化合物1、2、9、10和11对种子萌发具有较强的抑制作用。  相似文献   

7.
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   

8.
紫花重瓣玫瑰干品依次用CO2超临界萃取、水蒸汽蒸馏、乙醚萃取得到样品,样品经GC-MS分析鉴定71个化合物,据文献报道的香气特征成分并结合本文的研究结果综合分析,确定了12种香比强值和留香值较高的玫瑰干花香气特征成分:苯乙酸、3,4-二氢-4,4,5,7-四甲基-香豆素-6-醇、1,2-二甲氧基-4-丙烯基-苯(丁香酚甲醚)、芹菜脑、4-丙烯基-茴香醚(茴香脑)、苯甲醛、苯乙酮、5-烯丙-1,2,3-三甲氧苯(榄香素)、苯甲酸苯乙酯、苯甲酸甲酯、α-异-甲基紫罗兰酮,其中以苯乙酸、苯乙酮、苯甲酸苯乙酯、苯甲酸甲酯、榄香素、α-异-甲基紫罗兰酮组成了主要的玫瑰花香气。  相似文献   

9.
从长柄炭角菌(Xylaria longipes)的子实体中分离得到7个化合物,经波谱分析鉴定为3β-羟基-麦角甾-5,7,22-三烯(1)、麦角甾-4,6,8(14),22-四烯-3-酮(2)、integric acid(3)、1-羟基-6,8-二甲氧基-3-甲基-蒽醌(4)、3,9-二羟基-6,8-二甲氧基-3-甲基-3,4-二氢-1(2H)-蒽酮(5)、3β-羟基-5α,8α-过氧化麦角甾-6,22-二烯(6)和D-阿洛醇(7).  相似文献   

10.
对拟诺卡氏菌YIM90087的固体发酵提取物进行了化学成分研究,从中分离得到10个化合物。通过波谱数据分析,鉴定其结构分别为:(3S)-3-苄基-2,5-哌嗪二酮(1)、(3S,6S)-3-(2-丁基)-6-(1-羟乙基)-2,5-哌嗪二酮(2)、(3S,6S)-3-(2-丁基)-6-羟甲基-2,5-哌嗪二酮(3)、(4S)-4-苄基-1,3-恶唑-2,5-二酮(4)、6'-羟基-4,2',3',4'-四甲氧基-对三联苯(5)、(3S,6S)-3-(4-羟苄基)-6-异丁基-2,5-哌嗪二酮(6)、(3R,8aS)-3-异丙基-六氢吡咯并[1,2-a]吡嗪-1,4-二酮(7)、(3S,6S)-3-异丁基-6-甲基-2,5-哌嗪二酮(8)、(3S,6S)-3-苄基-6-(1-羟乙基)-2,5-哌嗪二酮(9)和(3S,6S)-3-苄基-6-(1-羟丙基)-2,5-哌嗪二酮(10)。化合物4目前只见化学合成报道,为新天然产物。  相似文献   

11.
Temperature changes were recorded continuously in eleven nests of Formica polyctena located in Southern Finland and the Czech Republic. Nest temperatures were recorded in the Czech site from 2003 to 2005 and in Finland during 2004 – 2005. Seasonal changes in nest temperature were very similar in both locations. During summer, the ants maintained a relatively high and constant temperature in their nest in both locations. Summer nest temperatures in Finland were higher than those in Czech during 2004 –2005 but did not differ from those in Czech during 2003– 2004. This indicated that the geographical differences were less important than difference between seasons. Nest temperature peaked in June. During summer, daily temperature fluctuations were significantly lower in Finland than in Czechia probably due to shorter nights in Finland. Apparent differences in daily temperature patterns were found in nests with different moisture in both locations. In dry nests, temperature peaked in the evening and decreased overnight, whereas the apparent increase was delayed to the night in wet nests. The spring increase in temperature in wet nests was much steeper that that in the dry ones when whole spring period is considered. During one day, temperatures fluctuated much more in dry nests than in wet ones. These differences seem to be caused by differences in thermal capacity between dry and wet nests. Received 24 July 2006; revised 19 February 2007; accepted 19 May 2007.  相似文献   

12.
Abstract

Sheep farming on Campbell Island began in 1895 and ended in 1931. The sheep population peaked at 8500 in 1910; only 1000 feral sheep were counted in 1961, but by 1969 there were 3000. The island was divided with a fence in 1970 and the sheep on the northern half were shot. Sheep continued to increase south of the fence, from 2088 in 1969 to 2521 in 1971 and, after a decline to 2400 in 1976, to 2861 in 1977. Breeding pairs of royal albatrosses numbered 2278 in 1958, 4344 in 1969, 5336 in 1976, and 4906 in 1977 - the first time the breeding population of this normally biennial breeder had been counted in two consecutive years. The number of feral cattle decreased from 20 in 1971 to 11 in 1977. These population trends are discussed in the context of changes to the flora in grazed and stock-free areas.  相似文献   

13.
Phytoplankton, submerged macrophytes, zoobenthos and zooplankton communities were studied concurrently in three lochs which progressively increased in trophic state. The phytoplankton showed a change in dominance from Bacillariophyceae (Pennales) and Desmidaceae in the mesotrophic Loch of the Lowes to Bacillariophyceae (Pennales) and Cyanobacteria in eutrophic Balgavies Loch and to Bacillariophyceae (Centrales) and Chlorophyceae in hypertrophic Forfar Loch. The Nygaard Compound phytoplankton quotient rose from 1.2 in the Lowes to 12 in Forfar. There was a decrease in number of species of submerged macrophytes, and in depth of colonisation from 5 m in the Lowes to 2 m in Forfar which was proportional to the decrease in mean transparency. Macrophyte biomass, however, increased in proportion to the concentration of total phosphorus in the lochs. There was a decrease in species of littoral zoobenthos, but an increase in density of profundal benthos from the Lowes to Forfar. Zooplankton also showed an increase in density with enrichment, accompanied by changes in dominance. Calanoida were dominant in the Lowes; Cladocera in Balgavies and Cyclopoda in Forfar. The importance of these differences in understanding the effects of progressive enrichment and to the management of the lochs is discussed.  相似文献   

14.
The young pistils in the melanthioid tribes, Hewardieae, Petrosavieae and Tricyrteae, are uniformly tricarpellate and syncarpous. They lack raphide idioblasts. All are multiovulate, with bitegmic ovules. The Petrosavieae are marked by the presence of septal glands and incomplete syncarpy. Tepals and stamens adhere to the ovary in the Hewardieae and the Petrosavieae but not in the Tricyrteae. Two vascular bundles occur in the stamens of the Hewartlieae and Tricyrtis latifolia. Ventral bundles in the upper part of the ovary of the Hewardieae are continuous with compound septal bundles and placental bundles in the lower part. Putative ventral bundles occur in the alternate position in the Tricyrteae and putative placental bundles in the opposite. position in the Petrosavieae. The dichtomously branched stigma in each carpel of the Tricyrteae is supplied by a bifurcated dorsal bundle.  相似文献   

15.
16.
Significant seasonal differences in intra- and interorgan prevalence, abundance and distribution of rodlet cells (RC) were observed in freshwater bream caught in May and August 1997 from a PCB-polluted lake, Lake Kernaala, Finland. In May, the majority of RCs in liver were seen in blood vessel endothelium, while in August most cells were located in the epithelium of the intrahepatic biliary ducts. In kidney, a significant increase in RCs in the columnar epithelium of the collecting ducts was observed from May to August. RCs in spleen were extremely rare in May, but were seen frequently in the endothelium of the splenic blood vessels in August. In gill and intestine, RCs were found in every tissue sample studied, with no statistical differences in their abundance or distribution between seasons. No RCs were seen in gonads. Total numbers of RCs increased dramatically from May to August in kidney and in spleen. The frequency of RCs corresponded strongly with the current phase of parasitic infections in liver, kidney, and spleen. It is concluded that RCs play a role in host defence mechanisms in fish, displaying induced expression at the times of peak parasitic prevalences.  相似文献   

17.
Aquaporins: water channel proteins of the cell membrane   总被引:37,自引:0,他引:37  
Aquaporins (AQP) are integral membrane proteins that serve as channels in the transfer of water, and in some cases, small solutes across the membrane. They are conserved in bacteria, plants, and animals. Structural analyses of the molecules have revealed the presence of a pore in the center of each aquaporin molecule. In mammalian cells, more than 10 isoforms (AQP0-AQP10) have been identified so far. They are differentially expressed in many types of cells and tissues in the body. AQP0 is abundant in the lens. AQP1 is found in the blood vessels, kidney proximal tubules, eye, and ear. AQP2 is expressed in the kidney collecting ducts, where it shuttles between the intracellular storage sites and the plasma membrane under the control of antidiuretic hormone (ADH). Mutations of AQP2 result in diabetes insipidus. AQP3 is present in the kidney collecting ducts, epidermis, urinary, respiratory, and digestive tracts. AQP3 in organs other than the kidney may be involved in the supply of water to them. AQP4 is present in the brain astrocytes, eye, ear, skeletal muscle, stomach parietal cells, and kidney collecting ducts. AQP5 is in the secretory cells such as salivary, lacrimal, and sweat glands. AQP5 is also expressed in the ear and eye. AQP6 is localized intracellular vesicles in the kidney collecting duct cells. AQP7 is expressed in the adipocytes, testis, and kidney. AQP8 is expressed in the kidney, testis, and liver. AQP9 is present in the liver and leukocytes. AQP10 is expressed in the intestine. The diverse and characteristic distribution of aquaporins in the body suggests their important and specific roles in each organ.  相似文献   

18.
Arginase, ornithine carbamoyl transferase (OCT) and arginine deiminase activities were found in cell-free extracts of Nostoc PCC 73102, a free-living cyanobacterium originally isolated from the cycad Macrozamia. Addition of either arginine, ornithine or citrulline to the growth medium induced significant changes in their in vitro activities. Moreover, growth in darkness, compared to in light, induced higher in vitro activities. The in vitro activities of arginase and arginine deiminase, two catabolic enzymes primarily involved in the breakdown of arginine, increased substantially by a combination of growth in darkness and addition of either arginine, or ornithine, to the growth medium. The most significant effects on the in vitro OCT activities where observed in cells grown with the addition of ornithine. Cells grown in darkness exhibited about 6% of the in vivo nitrogenase activity observed in cells grown in light. However, addition of external carbon (glucose and fructose) to cells grown in darkness resulted in in vivo nitrogenase activity levels similar to, or even higher than, cells grown in light. Growth with high in vivo nitrogenase activity or in darkness with the addition of external carbon, resulted in repressed levels of in vitro arginase and arginine deiminase activities. It is suggested that nitrogen starvation induces a mobilization of the stored nitrogen, internal release of the amino compound arginine, and an induction of two catabolic enzymes arginase and arginine deiminase. A similar and even more pronunced induction can be observed by addition of external arginine to the growth medium.  相似文献   

19.
The population biology of Bothriocephalus claviceps (Goeze) has been investigated in the European eel, Anguilla anguilla (L.), in three localities in southwest England. Monthly changes in prevalence and abundance show no statistically significant seasonality, in contrast to growth and reproduction of the cestode. The cestode reaches maximum size and becomes gravid mainly in summer. Gravid cestodes die and are lost soon after reproduction. This overlaps with recruitment of the new generation into eels, and may result in a rapid increase in infection levels and in a more over-dispersed distribution of the parasite in some localities, or in a more gradual change in infection levels and over-dispersion in others. Development and growth of the new generation may cease until the following spring, or continue at a slow rate over winter. Parasite numbers in each host decrease well before they actually reach maturity, since the majority of gravid individuals are present in those eels which harbour only one parasite. This suggests that few cestodes develop to maturity and most are lost from hosts as development proceeds.  相似文献   

20.
太原西山煤田太原组煤核中的科达植物雌性生殖器官   总被引:1,自引:0,他引:1  
报道了首次发现于我国的3种石化科达植物雌性生殖器官Cordaianthus sp.nov.,C.xishanensis sp.nov.和C.sp.,描述了它们的内部解剖构造特征,并与欧美植物区的雌性石化科达穗进行了比较,这些化石产于山西太原西山煤田太原组组上部7号煤层煤核中。  相似文献   

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