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1.
中国千金藤属植物化学分类概况   总被引:2,自引:0,他引:2  
探讨了各结构类型的异喹啉类生物碱在千金藤属植物中的分布规律及千金藤属植物的亲缘关系,在较原始的类群中,生物碱的结构类型和数量均较少,而在较进化的类群中内,其结构类型得到较大的发展,化合物的数量也相对增多,显示异喹啉类生物碱的结构类型及数量与属内植物群的进化有一定的对应关系,一些结构类型特化的生物碱和在植物界中分布极为狭窄的化学成分对亚属下各植物组的划分起着重要作用。  相似文献   

2.
本文详细讨论了苄基异喹啉生物碱的生源和进化趋势,化学结构类型的分布规律,植物来源,药理作用以及它们之间的联系性。研究表明:苄基异喹啉生物碱主要存在于较原始的木兰亚纲植物群中,阿朴菲型、双苄基异喹啉型、原小檗碱型为普遍存在的结构类型。由于按生源路线产生的不同结构类型在植物中呈现有规律的分布,因此苄基异喹啉生物碱可作为很好的分类学指标。  相似文献   

3.
全球紫堇属Corydalis约400余种,广泛分布于北温带和非洲南部地区。在我国,该属多种物种作为民间用药具有上千年历史。紫堇属植物富含异喹啉生物碱,对该类成分通常以回流、超声加热、湿法超微粉碎法和酶解辅助技术等方法提取,并使用溶剂分离法、硅胶柱色谱法、反向填料柱色谱法、HPLC法、离子交换树脂法、高效逆流色谱法和活性引导技术等方法进行分离纯化法。紫堇属生物碱有效部位或单体成分都具有较强药理活性,现代药理学表明,该属所含生物碱类成分对心脑血管、抗肿瘤、镇痛、消炎、保肝和抗血小板凝集等均具有显著的药理作用。本文对已报道的紫堇属植物生物碱类成分的结构类型、特征、药理作用以及提取分离方法研究进行综述,为植物药用化学成分富集和安全用药提供借鉴。  相似文献   

4.
植物异喹啉生物碱(plant isoquinoline alkaloids,PIAs)包括吗啡、可待因、加兰他敏及小糵碱等药用活性产物和其他天然活性产物。从植物中提取异喹啉生物碱,受制于低含量、种植季节及提取方法。人们开始研究利用微生物异源合成和改造天然异喹啉生物碱,从而获得低成本的药用活性物质。异喹啉生物碱合成途径长,反应复杂,为实现微生物异源合成带来了诸多挑战。随着合成途径和酶的解析和鉴定,合成生物学技术为在微生物中合成异喹啉生物碱提供了可能。综述了PIAs合成途径解析的最新进展,以及微生物异源合成PIAs的代谢工程策略,讨论了目前存在的问题和未来的发展趋势。  相似文献   

5.
异甾体生物碱类结构多变,药理活性多样,主要分布于百合科贝母属和藜芦属植物中。近十五年内共报道了80个新发现的异甾体生物碱类成分,药理活性涉及抗炎、镇痛、降压、平喘、抗血栓、胆碱酯酶抑制、抗病毒和抗肿瘤等作用。本文综述了2006至2020年间该类化合物的植物来源、化学结构及药理活性,并对该类化合物的未来研究探索进行了讨论与展望。  相似文献   

6.
丁三七即大花荷包牡丹(Dicentra macranlha Oliv.) 为紫堇科荷包牡丹属植物。分布于我国云南、四川、贵州和湖北西部。在云南昭通地区的彝良和大关县海拔1500—2600米山地有较丰富的资源。民间用其根茎治疗支气管炎,并有祛瘀消肿的作用。从同属植物中曾分离到多种异喹啉生物碱。丁三七的化学成分迄今未见报道。本文报道从云南昭通地区大关县产的丁三七根茎中分离得到的5个异喹啉生物碱的结构鉴定。  相似文献   

7.
异叶苣苔属地上茎的生长式样及其系统发育意义   总被引:3,自引:0,他引:3  
对异叶苣苔属植物地上茎形态发生过程的观察旨在揭示该属地上茎的生长式样。该研究发现异 叶苣苔属植物地上茎的生长式样并不是以往所认为的简单顶端生长。该属植物的顶芽已完全受到抑制。其地上茎实际上是萌发于小型叶叶腋的侧芽替代顶芽生长所形成的各级侧枝系统,即合轴分枝系统。异叶苣苔属植物地上茎的不分枝情况是位于大型叶叶腋的腋芽受到抑制所致,纯粹是一种次生现象,并不是尖舌苣苔族植物原始祖先的孑遗性状。尖舌苣苔族其他属植物地上茎的生长式样并不均是从异叶苣苔属植物的生长式样演化而来。出蕊苣苔属和异叶苣苔属植物地上茎的生长式样可能来自同一个不太远的祖先,但已经向着不同的方向演化。独叶苣苔属植物复杂的圆锥状对花聚伞花序并非从异叶苣苔属地上茎上部,即生殖生长部分退化而来,乃幼态成熟的复化过程所致。尖舌苣苔属的总状花序可能更接近尖舌苣苔族的原始祖先类型。  相似文献   

8.
在对世界异叶藓属(Kindbergia Ochyra)植物进行系统研究基础上,作者对中国分布的该属植物进行了分类学修订。结果表明:(1)中国分布的“树状异叶藓”[K.arbuscula(Broth.)Ochyra]、“异叶藓”[K.praelonga(Hedw.)Ochyra]和密枝燕尾藓[Bryhnia serricuspis(Müll Hal.)Y.F.Wang & R.L.Hu]为K.dumosa(Mitt.)Ignatov & Huttunen的错误鉴定;(2)因树状分枝的植物体、异形的茎枝叶、近及顶的强壮中肋和明显下延的叶基等特征不同于青藓科现存任一类群,故将中国分布的“异叶藓属”植物移入新建属——拟异叶藓属(Pseudokindbergia M.Li,Y.F.Wang,Ignatov & B.C.Tan)中;(3)拟异叶藓属区别于异叶藓属的主要形态特征为:假鳞毛半圆形至三角状半圆形,先端钝或平截;孢蒴倾立至水平;蒴盖圆锥形。(4)到目前为止,中国尚未发现异叶藓属植物的分布。  相似文献   

9.
本文就1982年至1994年来双苄基异喹啉类生物碱(BBI)在植物资源,化学成分,生理活性等方面的研究作一简要概述。  相似文献   

10.
本文对双基异喹啉生物碱的化学反应作了总结  相似文献   

11.
The Cuban species of Calisto are reviewed based on the morphology of adult and immature stages, as well as DNA sequences of six genes (COI, EF1α, wingless, GAPDH, RpS5, CAD). A new species, Calisto occultasp. n., is described from the northeastern Cuban mountains. Calisto smintheus Bates, 1935 and Calisto bruneri, Michener 1949 are revised and revalidated. A new status, the species level, is proposed for Calisto brochei, Torre 1973, Calisto muripetens, Bates 1939 and Calisto bradleyi, Munroe 1950. The immature stages of Calisto smintheus, Calisto brochei,and Calisto occulta are described for the first time, and those of Calisto herophile, Hübner 1823 are redescribed. Useful morphological characters for adults are the shape and conspicuousness of androconial patch, the number and relative size of white dots on underside of hindwing, the shape of aedeagus, the shape of digitiform projection of genitalia valve, the shape and relative size of tegumen and uncus, the relative size of female genitalia, the height of sterigmal ring dorsal crown of the latter, and the relative size of corpus bursae and ductus bursae. For the immature stages, the most important characters are the color pattern of head capsule, the number and width of longitudinal lines of body, in the larvae; and the color pattern and the absence or presence of dorsal ridges on the abdomen of pupae. The phylogenetic relationships between the Cuban Calisto species are quite robust and well-supported; however, conflict between mitochondrial and nuclear datasets was detected in Calisto brochei, Calisto muripetens and to a lesser degree in Calisto bradleyi.  相似文献   

12.
Numbers of species and genera,endemic genera,extant primitive genera,relationship and distribution patterns of presently living Chenopodiaceae(two subfamilies,12 tribes,and 118 genera)are analyzed and compared for eight distributional areas,namely central Asia,Europe,the Mediterranean region,Africa,North America,South America, Australia and East Asia. The Central Asia,where the number of genera and diversity of taxa are greater than in other areas,appears to be the center of distribution of extant Chenopodiaceae.North America and Australia are two secondary centers of distribution. Eurasia has 11 tribes out of the 12,a total of 70 genera of extant chenopodiaceous plants,and it contains the most primitive genera of every tribe. Archiatriplex of Atripliceae,Hablitzia of Hablitzeae,Corispermum of Corispermeae,Camphorosma of Camphorosmaea,Kalidium of Salicornieae,Polecnemum of Polycnemeae,Alexandra of Suaedeae,and Nanophyton of Salsoleae,are all found in Eurasia,The Beteae is an Eurasian endemic tribe,demonstrating the antiquity of the Chenopodiaceae flora of Eurasia.Hence,Eurasia is likely the place of origin of chenopodiaceous plants. The presence of chenopodiaceous plants is correlated with an arid climate.During the Cretaceous Period,most places of the continent of Eurasia were occupied by the ancient precursor to the Mediterranean,the Tethys Sea.At that time the area of the Tethys Sea had a dry and warm climate.Therefore,primitive Chenopodiaceae were likely present on the beaches of this ancient land.This arid climatic condition resulted in differentiation of the tribes Chenopodieae,Atripliceae,Comphorosmeae,Salicornieae,etc.,the main primitive tribes of the subfamily Cyclolobeae. Then following continental drift and the Laurasian and Gondwanan disintegration, the Chenopodiaceae were brought to every continent to propagate and develop, and experience the vicissitudes of climates, forming the main characteristics and distribution patterns of recent continental floras. The tribes Atripliceae, Chenopodieae, Camphorosmeae, and Salicornieae of recent Chenopodiaceae in Eurasia, North America, South America, southern Africa, and Australia all became strongly differentiated. However, Australia and South America, have no genera of Spirolobeae except for a few maritime Suaeda species. The Salsoleae and Suaedeae have not arrived in Australia and South America, which indicates that the subfamily Spirolobeae developed in Eurasia after Australia separated from the ancient South America-Africa continent, and South America had left Africa. The endemic tribe of North America, the tribe Sarcobateae, has a origin different from the tribes Salsoleae and Suaedeae of the subfamily Spirolobeae. Sarcobateae flowers diverged into unisexuality and absence of bractlets. Clearly they originated in North America after North America had left the Eurasian continent. North America and southern Africa have a few species of Salsola, but none of them have become very much differentiated or developed, so they must have arrived through overland migration across ancient continental connections. India has no southern African Chenopodiaceae floristic components except for a few maritime taxa, which shows that when the Indian subcontinent left Africa in the Triassic period, the Chenopodiaceae had not yet developed in Africa. Therefore, the early Cretaceous Period about 120 million years ago, when the ancient Gondwanan and Laurasian continents disintegrated, could have been the time of origin of Chenopodiaceae plants.The Chinese flora of Chenopodiaceae is a part of Chenopodiaceae flora of central Asia. Cornulaca alaschnica was discovered from Gansu, China, showing that the Chinese Chenopodiaceae flora certainly has contact with the Mediterranean Chenopodiaceae flora. The contact of southeastern China with the Australia Chenopodiaceae flora, however, is very weak.  相似文献   

13.
The creation of the Veterinary Schools in the 18th century would reveal a plethora of scientists, some of whom would be the precursors of Pasteur, some rivals, others followers collaborators or friends of the Master. Among the precursors let us name Chabbert, Huzard, Girard, Delafond, Renault, Toussaint, Galtier ; among the rivals: Chauveau, Arloing, Cornevin and Thomas; among the followers, collaborators or friends of Pasteur: Bouley, at first a resolute spontaneist, then the most fervent in defense of Pasteur (President of the Academy of Medicine and of the Academy of Sciences) and Nocard, Director of the School in Alfort, an important collaborator of Pasteur. Later, there was Leclainche, who created the International Office of Epizootics, and who was President of the Academy of Sciences; Guérin, who with Calmette developed the BCG vaccination; Ramon, the father of anatoxins (vaccines against diphtheria, and tetanus, combined vaccines, adjuvants to immunity). Thus, the creation of the Veterinary Schools contributed not only to the evolution of the notion of contagion, to the amelioration of animal health and the economics of agricultural production, but also to serious advances in human care, and to the protection of public health.  相似文献   

14.
The development of new taxonomical theories and approaches, particularly molecular phylogenetics, has led to the expansion of traditional morphology-based taxonomy into the concept of "integrative taxonomy." Taxonomic knowledge has assumed greater significance in recent years, particularly because of growing concerns over the looming biodiversity crisis. Since its establishment in 1938, the Kunming Institute of Botany (KIB), which is located in Yunnan province in Southwest China, has focused attention on the taxonomy and conservation of the flora of China. For the forthcoming 80th anniversary of KIB, we review the achievements of researchers at KIB and their associates with respect to the taxonomy of land plants, fungi, and lichen. Major taxonomic advances are summarized for families of Calymperaceae, Cryphaeaceae, Lembophyllaceae, Neckeraceae, Polytrichaceae and Pottiaceae of mosses, Pteridaceae and Polypodiaceae of ferns, Taxaceae and Cycadaceae of gymnosperms, Asteraceae, Begoniaceae, Ericaceae, Euphorbiaceae, Gesneriaceae, Lamiaceae, Orchidaceae, Orobanchaceae, Poaceae, Theaceae and Urticaceae of angiosperms, Agaricaceae, Amanitaceae, Boletaceae, Cantharellaceae, Physalacriaceae Russulaceae, Suillaceae and Tuberaceae of fungi, and Ophioparmaceae and Parmeliaceae of lichens. Regarding the future development of taxonomy at KIB, we recommend that taxonomists continue to explore the biodiversity of China, integrate new theories and technologies with traditional taxonomic approaches, and engage in creative monographic work, with support from institutions, funding agencies, and the public.  相似文献   

15.
During the years 1996 and 1997, a team of the Laboratory of Prehistory, National Museum of Natural History, Paris, and of the Departments of Archaeology, Karachi and Peshawar University, Pakistan, leads the first prehistoric field investigation in the District of Chitral, Hindu Kush, close to the Wakhan Corridor (the Amu Daria course in the Pamir). Problematics are the origins and the becoming of the Epipaleolithic/Neolithic hunters-gatherers known in the Pamir Plateau and the Gissar Range, the lithics tradition of which share common roots with the Sub-Himalayan Soanian tradition (Mode 1). A second field investigation has been conduced in the North West India, where Soan developed from Early Pleistocene, in the Frontal Range of the Siwaliks and Himachal Pradesh during the years 2003, 2005 and 2006 in cooperation with the Department of Archaeology and Museums of Punjab, India. New discoveries in both countries support new hypothesis for the understanding of human evolution in Asia and Homo sapiens origins.  相似文献   

16.
云南复叶耳蕨属的分类修订   总被引:7,自引:0,他引:7  
研究了云南产复叶耳蕨属植物,提出了新的分类处理。云南共有本属植物20种2变种,其中包括1新组,3个改级新组合,7个云南分布新记录,并清理出了54个云南及其他省区种类的新异名。  相似文献   

17.
Here we report the results of a comprehensive biogeochemical monitoring of Rostherne Mere in 1998, including changes in dissolved oxygen, organic carbon and nitrogen, nitrate/nitrite, ammonia, Al, Na, S, K, Mg, Ca, Si, Fe, Mn, orthophosphate, particulate N & P, suspended solids, temperature, pH, chlorophyll-a and zooplankton. The results demonstrated the major influence of primary producers on the overall geochemical cycling of N, P and Si, and suggested that the significance of zooplankton might have been previously underestimated. For major anions and cations, however, the influence of biota on lake water concentrations appeared to be negligible, reflecting the fact that these chemicals were present far in excess of plankton requirements. Thus changes in concentrations of Ca, K, Na, Mg and S were rather limited and must have reflected changes in hydrological and meteorological parameters. K, however, demonstrated a transitional pattern, reflecting some influence of biological uptake. During the stratification period, the slow processes of bacterial decomposition in the hypolimnion gradually released chemicals contained in the materials accumulated in the bottom layer, remarkably increasing the concentrations of dissolved compounds of those elements present in amounts comparable with the pool stored in the sedimenting detritus (e.g. orthophosphate P, ammonia N, Si and DOC). The decomposition also resulted in a drop in the redox potential, followed by partial denitrification and chemical release from the sediments. The hypolimnion of the Mere was confirmed to remain at the stage of Mn release, characterised by accumulation of DOC, orthophosphates, ammonia and initial stages of denitrification. High levels of P released from the sediments during the stratification period suggest that the lake’s recovery after sewage diversion might be further delayed.  相似文献   

18.
19.
性状(Trait)或功能性状(Functional trait)是植物、动物和微生物等对外界环境长期适应和进化后所呈现出来的可量度的特征,也是人们认识自然、利用或改造自然的重要途径和技术手段。近几十年来,科学家对植物、动物和微生物功能性状的研究取得了令人瞩目的成就,尤其在物种水平的植物叶片和根性状的研究领域;然而,自然生态系统是复杂的,植物、动物和微生物自身的多种性状间及其不同生物间性状的相互作用是广泛存在的,因此需要跨学科、系统性、集成式地调查和研究。以中国东部南北样带(NSTEC)森林生态系统为对象开展了植物、微生物和土壤性状的综合测定;基于其核心的研究结论并适当整合NSTEC前期的相关研究成果,希望能给性状研究提供新的调查模式和分析思路。沿NSTEC从热带雨林到寒温带针叶林3700km样带选取了9个地带性森林生态系统,在群落结构调查基础上对群落内所有植物种类(总计1177物种)开展了系统性的性状测定(叶-枝-干-根多元素含量,叶片形态性状-气孔性状-解剖性状-叶绿素含量-多元素含量-非结构性碳水化合物、细根形态性状-解剖性状-多元素含量等),测定了土壤微生物群落结构、酶活性、土壤有机质结构与组成、土壤碳氮周转及其温度敏感性等参数。基于上述数据,不仅按传统途径系统性地探讨了植物、微生物和土壤多种性状的纬度变异规律与影响因素;还从不同角度探讨了"如何科学地将器官水平测定性状推导至天然森林群落水平"科学难题,并从多个性状角度建立了自然森林生态系统中性状与功能的定量关系。在此基础上提出"性状网络"和"生态系统性状"概念,以其更好地用于揭示自然界复杂的森林生态系统,为验证和发展生态学理论、探讨多种性状间协同(权衡)的生态系统生产力优化机制提供重要的数据支撑。希望通过解决性状尺度拓展的技术难题,未来将传统性状研究拓展至群落或生态系统水平,并与高速发展的宏观观测手段(遥感观测、通量观测、模型模拟)有机结合,使性状研究更好地服务于区域乃至全球性的生态环境问题。  相似文献   

20.
Nine of 10 genera and 119 of approximately 240 species of the Pinaceae occur in China, including 67 endemic species and two endemic genera. In this paper, the distributional maps of all the genera of the Pinaceae are presented (fig. 1-8). The horizontal and vertical distributions of species in each genus are discussed. The analysis of the distribution patterns of the genera indicates that some genera, such as Keteleeria, Tsuga, Pseudotsuga, Cathaya and Pseudolarix, are restricted to the area south of the Qinling Mountains and the Huaihe River, and the others, i. e. Picea, Abies, Larix and Pinus, extend northward to northeastern China. However, all of the genera except Keteleeria and Pinus are not found in very dry areas and tropical mountainous regions of China. The monotypic genera, Cathaya and Pseudolarix, are distributed in eastern and central China. The genus Keteleeria consists of 10 species, 7 of which are concentrated in southern Guizhou, northern Guangxi, southwestern Hunan and easternmost Yunnan. The distribution of the remaining 6 genera shows the maximum concentration in western Sichuan and northwestern Yunnan. (Figs. 2-8). Furthermore, more than third of species of the Pinaceae (37.8%) are also concentrated in western Sichuan and northwestern Yunnan. where a great variety of habitats and different topographic features occur. It is apparent that to conduct our systematic and evolutionary studies on this family in these region is especially needed. The relations between the areal size and the tolerance of species are discussed. The distributions of macrofossils and microfossils of the genera of the Pinaceae ia China are given, and it has been proved that areas of most genera of the family were considerably larger in the past. than at present.  相似文献   

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