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1.
中国无患子科的地理分布   总被引:11,自引:1,他引:10  
无患子科是一个乏热带分布科,全世界有144属,1680种,本文着重阐述:1.无患子科的分类系统及演化;2.世界无患子科的地理分布;3.中国无患子科的地理分布;4.无患子科的早期化地点及散布途径。结果表明无患子科现代分布变异中心在亚洲(印度-马西亚)-非洲-南美洲。中国无患子科有25属,54种,特有成分外,均与印度一马来西亚共有,大多数位于分布区的边缘。根据化石记录及现代及分布推断,无患子科可能在白  相似文献   

2.
本文综述了无患子皂苷生物活性和在医药、日化、农业领域应用研究进展,为综合开发利用无患子这一古老而传统的药用植物提供科学依据。  相似文献   

3.
不同居群无患子果实组成比较研究   总被引:1,自引:0,他引:1  
无患子是一种广泛分布于我国南方的乔木,本文针对不同居群无患子全果的物理组成、种仁油脂及氨基酸组成等方面进行比较研究.福建无患子种仁含油率最高,达到42.8%;四川无患子种子含油率最高,达到13.7%.无患子油脂的脂肪酸碳链长度为C16~C24,其中C16~C20的脂肪酸均占92%以上,不饱和脂肪酸79%~85%.种仁氨...  相似文献   

4.
无患子中两个新的大戟烷型三萜皂甙   总被引:2,自引:0,他引:2  
从无患子科无患子(Sapindus mukorossi Gaertn.)根中分离到两个新的大戟烷型三萜皂甙SapimukosideA(1)和SapimukosideB(2)。运用波谱和化学方法鉴定它们的结构为3-O-α-L鼠李吡喃糖基-(1→2)-[α-L-阿拉伯吡喃糖基-(1→3)]-β-D-葡萄吡喃糖基-21,23R-epoxyl tirucall-7,24R-diene-3β,21-diol(1)和3-O-α-L-鼠李吡喃糖基-(1→6)-β-D-葡萄吡喃糖基21,23R-epoxyl tirucall-7,24R-diene-3β,21-diol(2)。  相似文献   

5.
从无患子科无患子(Sapindus mukorossi Gaertn.)根中分离到两个新的大戟烷型三萜皂甙Sapimukoside A (1) 和Sapimukoside B (2).运用波谱和化学方法鉴定它们的结构为3-O-α-L-鼠李吡喃糖基-(1→2)-[α-L-阿拉伯吡喃糖基-(1→3)]-β-D-葡萄吡喃糖基-21, 23R-epoxyl tirucall-7, 24R-diene-3β, 21-diol (1) 和3-O-α-L-鼠李吡喃糖基-(1→6)-β-D-葡萄吡喃糖基21, 23R-epoxyl tirucall-7, 24R-diene-3β, 21-diol (2).  相似文献   

6.
无患子属植物的化学成分及生物活性研究进展   总被引:2,自引:0,他引:2  
本文对近30年来无患子属植物的化学成分和生物活性研究进展进行了综述,为该属植物的进一步开发利用提供参考.无患子属植物的化学成分主要包括挥发油、三萜皂苷、倍半萜苷类化合物等,这些化合物具有抑菌、抗肿瘤、保肝和表面活性等多方面的生物活性.  相似文献   

7.
无患子皂素是一种天然的表面活性剂,具有良好的乳化、分散、发泡、湿润等功效。采用超声波辅助法低水比无患子皂素提取优化工艺为:超声频率20 kHz,超声时间20 min,料液比1∶6,超声功率800 W,提取温度60℃,皂素提取得率为37.27%。超声波辅助法提取无患子皂素可以减少过程用水量,降低能耗,提高皂素得率。  相似文献   

8.
无患子分布范围广,不同种源果实经济性状差异明显,具体由哪些环境因子对无患子果实经济性状变异起主要作用尚不明确.本文以我国无患子自然分布的东、西、南、北4个边界的4个省份为调查单元,将收集到的47株天然种质为研究对象,测定各优株果实经济性状,通过相关性分析、冗余分析研究无患子果实经济性状与环境因子的互作规律.结果表明:果...  相似文献   

9.
以福建建宁县无患子为材料,观测果实生长动态,并采用Logistic方程对生长指标进行曲线拟合,观察生长过程中果皮显微结构变化,确定无患子果实生长发育的重要时期,为无患子的高效栽培管理和果实采收策略的制定提供科学依据。结果表明:(1)无患子果实生长、果皮总皂苷和种子油脂的积累规律相似,总体上呈Logistic增长模型的单“S”型曲线;果皮总皂苷和种子油脂的主要积累时期分别为45~90 DAP(花授粉后天数)和75~105 DAP。(2)无患子果皮除含有角质层、表皮细胞、厚角细胞、薄壁细胞、维管束、石细胞等基本结构外,还含有溶生式分泌腔和草酸钙簇晶等特征性结构;随着果实生长,分泌腔体积逐渐变大。(3)根据果实生长变化规律和Logistic方程拟合结果,可将无患子果实生长发育进程划分为生长初期(0~30 DAP)、速生期(30~90 DAP)、生长后期(90~120 DAP)和果实成熟期(120~150 DAP)4个阶段。在生产实践中果实成熟期内均适合果实采收,其中135和150 DAP分别为果实皂用和油用采收的最佳时期,此外还应根据每年天气状况对果实采收时间进行适当调整。  相似文献   

10.
目的探讨无患子及其制剂的鉴别方法。方法采用薄层色谱法在不同条件下进行薄层色谱考察,选择适宜的薄层色谱条件。结果最佳薄层色谱条件为:以正丁醇-乙酸乙酯-水-浓氨水(40∶10∶50∶1;V∶V∶V∶V)上层液为展开剂,室内环境中展开,晾干,喷5%磷钼酸乙醇液,105℃加热至斑点清晰,在日光下检视,无患子及其在制剂中的成分分离效果良好,色谱斑点清晰,耐用性好。结论该法操作简便可靠,分离度较好,可作为无患子及其制剂的鉴别方法。  相似文献   

11.
Phylogenetic definitions and taxonomic philosophy   总被引:4,自引:0,他引:4  
An examination of the post-Darwinian history of biological taxonomy reveals an implicit assumption that the definitions of taxon names consist of lists of organismal traits. That assumption represents a failure to grant the concept of evolution a central role in taxonomy, and it causes conflicts between traditional methods of defining taxon names and evolutionary concepts of taxa. Phylogenetic definitions of taxon names (de Queiroz and Gauthier 1990) grant the concept of common ancestry a central role in the definitions of taxon names and thus constitute an important step in the development of phylogenetic taxonomy. By treating phylogenetic relationships rather than organismal traits as necessary and sufficient properties, phylogenetic definitions remove conflicts between the definitions of taxon names and evolutionary concepts of taxa. The general method of definition represented by phylogenetic definitions of clade names can be applied to the names of other kinds of composite wholes, including populations and biological species. That the names of individuals (composite wholes) can be defined in terms of necessary and sufficient properties provides the foundation for a synthesis of seemingly incompatible positions held by contemporary individualists and essentialists concerning the nature of taxa and the definitions of taxon names.  相似文献   

12.
The fossil record of bryophytes is generally poor and infertile plants attributable to liverworts and mosses could also be thalloid vascular plant gametophytes or herbaceous lycophytes respectively. The paucity of the bryophytic record could be the result of relatively rapid degradation of bryophytic material in comparison to that of vascular plants, the absence of lignified cells in bryophytes sustaining this belief. However, certain organs of bryophytes are as robust as those of vascular plants (e.g. spores) and the hydroxybenzofuran polymers produced by some mosses could be of similar preservational resistance to lignins. A simplistic experiment to test the relative resistance to decay of bryophytic material has been undertaken. Its findings suggest that bryophytic plant material has a similar preservational potential to that of a selected vascular plant, particularly in organic rich sediments. This result may be construed to imply that bryophytes were indeed less abundant in the preservational environments of the Coal Measures than might be expected on the basis of current palaeoenvironmental reconstructions.  相似文献   

13.
Research on the influence of sea level variations on the benthic faunas have been carried out in the Upper Ordovician of Sardinia. Study of the depositional facies and sequence analysis of the upper part (Lower Ashgill) of the Portixeddu Formation led to the identification of the sedimentary environments. Cystoids and crinoids are associated to bryozoans and brachiopods in most levels. The numerical analysis of associations and megaguilds shows that crinoids and cystoids have a higher frequency in the proximal and median facies of the upper offshore. The columnal association characterized by Conspectocrinus celticus and the coronoid Mespilocystites tregarvanicus has been discovered in the upper part of the formation. This material and complementary samples from Upper Ordovician of Sardinia and Kabylia (Algeria) bring additional data on the systematic and show the wide distribution of this fauna outside of the Ibero-armorican domain. The distribution of this echinoderm association supports a palaeogeographical position of the Ibero-armorican domain and Sardinia within the north gondwanan margin during the Lower Palaeozoic.  相似文献   

14.
Found in Chiapas (South-East of Mexico), Praealveolina michaudi nov. sp. and Chubbina jamaicensis (of Campanian-Maestrichtian age) are described, both evolved from Nummoloculina sp. while Raadshoovenia guatemalensis (upper Paleocene-lower Eocene) arises from Quinqueloculina. We precisely analyze and modelize the nepionic coiling during the evolutionary change from Miliolacea to Alveolinacea. During ontogenesis as well as during phylogenesis, quinqueloculine coiling progresses to streptospiral and then to planispiral chamber arrangement with the increase of volume of embryo and of chambers. Appearance of these large foraminifers are understood as a consequence of the rise of K-strategies in their mode of life, following the development of photosynthetic symbioses.  相似文献   

15.
突变文库的构建是定向进化研究过程中一个关键步骤,主要利用天然存在的系统或者人工合成的分子技术来产生多样性核酸分子文库,为制备和筛选具有一定特性的蛋白酶、多肽、人工抗体等提供庞大的遗传基因库,也可用于合成生物学中相关基因元件的研究与筛选,为目标生物制品的高效工业化生产提供动力。随着对突变文库构建技术研究的日益深入,各种文库构建策略相继被开发出来,并在生物能源、生物化工、生物医药、生物试剂和食品工业等方面得到了广泛的应用。然而,定向进化中的文库构建策略多有不同,各种突变文库构建技术的核心方法也在不断创新。主要介绍近年来实验室中人工合成多样性文库的前沿技术,并对文库构建技术在自动化和智能化方向的发展进行了展望。  相似文献   

16.
A phylogenetic analysis of 123 morphological characters of basal waterfowl (Aves: Anseriformes) and other selected avian orders confirmed that the screamers (Anhimae: Anhitn-idae) are the sister-group of other waterfowl (Anseres), and that the magpie goose (Anseranatidae: Anseranas semipalmata) is the sister group of other modern waterfowl exclusive of screamers (Anatidae sensu stricto). The analysis also supports the traditional hypothesis of the gallinaceous birds (Galliformes) as the sister group of the Anseriformes. Presbyornis, a fossil from the early Eocene of Wyoming and averred by Olson & Feduccia as showing that the Anseriformes were derived from shorebirds (Charadriiformes), was found to represent the sister group of the Anatidae. Associated hypotheses by Olson & Feduccia concerning the implications of Presbyornis for the phylogenetic relationships of flamingos (Phoenicopteriformes), the position of the Anhimidae within the waterfowl, relationships among modern Anatidae, and a plausible evolutionary scenario for waterfowl also are rejected. Analyses revealed that cranial characters were critical to the establishment of the Galliformes as the sister group of the Anseriformes; exclusion of the Anhimidae, especially in combination with Anseranas, also undermined the support for this inference. Placement of Presbyornis as the sister group of the Anatidae casts doubt on the role suggested by Feduccia of ‘transitional shorebirds' in the origin of modern avian orders, and calls into question the concept of ‘fossil mosaics’. The phylogenetic hypothesis is used to reconstruct an evolutionary scenario for selected ecomorphological characters in the galliform-anseriform transition, to predict the most parsimonious states of these characters for Presbyornis, and to propose a phylogenetic classification of the higher-order taxa of waterfowl. This re-examination of Presbyornis also is used to exemplify the fundamental methodological shortcomings of the intuitive approach to the reconstruction of phylogenetic relationships.  相似文献   

17.
The archaeological excavation of the cave of the Gardon has brought to light a dilated and nearly continuous stratigraphy for the Neolithic era. The analysis of lithic industry has showed the existence of variations between those neolithic layers, which are independents of the technological processes of tools productions. Four criteria allow us to characterize the occupation’s type of each layer. Compared to the excavations data and to sedimentological analysis, these results allow us to display the evolution of the intensity of occupations of the cave throughout the whole Neolithic.  相似文献   

18.
The natural host range of entomopathogenic nematodes of the genera Steinernema and Heterorhabditis can be defined as the range of insects which indigenous nematode populations use for propagation. Information on the natural host range is rare. However, based on records of insects found to be naturally infected with nematodes, some conclusions regarding the natural host range of some Steinernema spp. and Heterorhabditis spp. are presented. Reports of indigenous nematode populations impacting on insect populations can be divided between relatively balanced, long-lasting nematode-host associations and unbalanced, short-lasting epizootics. Examples of the augmentation and inoculative introduction of nematodes in agriculture and forestry ecosystems are presented. Based on current knowledge, nematode reproduction strategies are discussed and indications of the risk involved in the release of non-indigenous nematodes are given.  相似文献   

19.
The reference ranges of the trace elements Al, As, Be, B, Cd, Co, Cu, Fe, Mn, Mo, Ni, Pb, Li, Rb, Se, Sr, and Zn were determined by inductively coupled plasma-mass spectrometry (ICP-MS) in sera of a group of free-ranging plains viscachas of the pampa grasslands of Argentina. The values were compared with those of a small group of captive plains viscachas of the Zurich Zoo with diabetes and bilateral cataracts. In addition, a method for digestion of whole-blood samples is described for the trace element determination. Significant differences in the concentration of trace elements in the two groups of animals are discussed. No correlation was found between the levels of selenium and of other trace elements compared to the formation of cataracts.  相似文献   

20.
The field slug, Deroceras reticulatum (Muller), is probably the most damaging and widespread species of slug, causing severe economic losses in a broad range of crops in temperate zones throughout the world. Investigations into the role of predation in the population dynamics of this species required a biochemical system which was capable of identifying the remains of this slug in the crop contents of predators, and distinguishing them from those of other molluscs. A monoclonal antibody was developed (IgM isotype). This was capable of separating, in an enzyme-linked immunosorbent assay, D. reticulatum from the related D. caruanae (Pollonera) and all molluscs and other invertebrates tested, with the unexpected exceptions of New Zealand flatworms, Artioposthia triangulata (Deny) and the millipede Polymicrodon polydesmoides (Leach). Characterization of the antibody and assay demonstrated that the system could clearly detect as little as 11.6 ng of D. reticulatum protein in 200 mu l of buffer. Slug remains could be identified as such in the crops of the carabid predator Pterostichus melanarius Illiger for 38.1 h, while the antibody-antigen reaction declined to half of that measured immediately following consumption, after 12.9 h. A practical and highly sensitive system was therefore developed, using the first species-specific monoclonal antibody available for the investigation of predation on slugs.  相似文献   

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