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1.
The carbon-13 nuclear magnetic resonance (NMR) spectra of modern resins have been used to characterize their botanical sources. Resins from four of the principal diterpenoid resinproducing genera, Agathis, Hymenaea, Pinus, and Araucaria, give distinct NMR spectra under conditions of normal and interrupted decoupling. The genus Wollemia gives the same spectra as Agathis. Samples from the triterpenoid resin-producing family Burseraceae and of gum resins were recorded for comparison. Resin samples from unknown or uncertain sources then were examined and assigned to their botanical sources.  相似文献   

2.
The chemical composition of fossil resins from Middle to Late Eocene lignite samples of the western margin of Bengal Basin, India, has been chemically analyzed to infer their botanical affinity. The terpenoid content of the resins has been characterized using gas chromatography–mass spectrometry (GC–MS). Sesquiterpenoid and triterpenoid components show close affinity with those in extant dammer (Dipterocarpaceae) resin (class II) and indicate the common occurrence of dipterocarps in the forest growing under warm tropical climate in the area at that time. Rich palynofloral assemblages dominated by Dipterocarpaceae pollen grains recovered from the lignite samples corroborate the chemical data.  相似文献   

3.
The soldier defense secretions of advanced neotropical termites of the genus Subulitermes (Isoptera, Nasutitermitinae) contain diterpenes identicalto those found in Nasutitermes species, while soldiers of the primitive mandibulate nasute genera Cornitermes, Armitermes and Rhynchotermes lack diterpenoid compounds. It now appears improbable that the elongate nasus and intimately associated terpenoid defense secretions evolved from a primitive mandibulate ancestor independently along two phyletic branches. An alternate hypothesis is proposed in which morphological divergence from a common diterpene-producing ancestor may have occurred.  相似文献   

4.
Chemosystematics is a common tool in systematics and taxonomy of extant plants. Terpenoids have been found to be especially valuable for chemosystematic investigations of conifers. A review of data in the extensive literature revealed some characteristic distribution patterns of sesqui-, di-, and triterpenoids in extant conifer families. The numerous terpenoids can be assigned to approximately 40 sesquiterpenoid, 17 diterpenoid, and only a few triterpenoid structural classes. Some of these terpenoid classes (e.g., cadinanes, humulanes, labdanes, pimaranes) are unspecific and distributed among all conifers. Other structural classes occur in certain clusters of families (e.g., totaranes in Podocarpaceae, Taxodiaceae, and Cupressaceae s.str.) or were restricted to species of only one conifer family (e.g., cuparanes in Cupressaceae s.str.). Cupressaceae s.str. and Taxodiaceae show great similarities in their terpenoid composition (cedranes, thujopsanes) but can be separated by the occurrence of some sesquiterpenoids (cuparanes, widdranes), which were hitherto known only in Cupressaceae s.str. This supports a monophyletic clade of Cupressaceae s.str. within the major Taxodiaceae/Cupressaceae lineage (= Cupressaceae s.l.). Pinaceae differ from the other conifer families because they commonly lack several diterpenoid classes (phenolic abietanes, tetracyclic diterpenoids) and because they contain some distinct sesquiterpenoids (longicyclanes, sativanes), diterpenoids (cembranes), and triterpenoids (serratanes, lanostanes). With the exception of diterpenoid alkaloids (taxanes), Taxaceae contain terpenoids common in the other conifer families. This supports their inclusion as a separate family in the major conifer clade.  相似文献   

5.
Leaf resins in the leguminous genera Hymenaea and Copaifera may play a role in restricting infection by the associated leaf fungus, Pestalotia. We tested this hypothesis by assessing growth of the geographically widespread Pestalotia subcuticularis presented with different compositions of resins. Leaf resins of Hymenaea and Copaifera are composed of the same suite of sesquiterpene hydrocarbons, but these vary quantitatively to form discrete compositional patterns among individuals and populations. Leaf resins may also contain sesquiterpene oxides; caryophyllene oxide, which may have been formed from the caryophyllene precursor common in these resins, inhibited fungal growth in vitro.  相似文献   

6.
The oleanolic and ursolic acid contents from 88 taxa of Lamiaceae (19 genera, 66 species, 8 subspecies, 9 varieties and 5 hybrids) were investigated using gas chromatography. Both triterpenoid acids were present in all of the investigated taxa, but the plants belonging in the subfamily Nepetoideae produced significantly higher amounts than those in the subfamily Lamioideae. The oleanolic acid content ranged from traces to 1.840% dry weight, and that of ursolic acid from traces to 4.019% dry weight.  相似文献   

7.
为探讨瑞香科沉香亚科的分类学地位,结合其他亚科植物的化学成分类型,对从沉香属植物分离到的各类化学成分进行了综述。从二萜和黄酮(烷)的成分类型判断,沉香亚科的进化地位低于瑞香亚科;从三萜成分类型来看,其地位又比Gonystyloideae亚科稍高;同时2-(2-苯乙基)色酮类和二苯基甲酮类成分为沉香属甚至沉香亚科的特征性成分。因此,沉香亚科是瑞香科中进化程度相对较低的类群,处于瑞香亚科和Gonystyloideae亚科之间。  相似文献   

8.
本文基于野外调查和文献资料整理, 对罗霄山脉种子植物区系及其自北向南5条中型山脉之间的区系过渡性特征进行了系统分析。结果表明: (1)该区域内野生种子植物有179科1,107属4,314种; 区系表征科主要以亚热带山地为现代分布中心。科的区系组成为: 单型科25科, 寡种科61科, 单型属465属, 寡种属432属, 呈现出区系特征上的孑遗性, 也显示出本地区系成分与典型热带成分及典型温带成分间存在密切交流。(2)科的地理成分共分为10个类型, 以热带性成分占明显优势, 热带性科83科及温带性科40科分别占非世界性科总数的67.48%和32.52%; 属的地理成分包括15个分布区类型, 以温带成分占优势, 温带性属534属及热带性属484属分别占非世界性属总数的52.46%和47.54%。属分布区类型以泛热带分布、热带亚洲分布、北温带分布、东亚分布为主, 体现出本地区与古热带植物区系及温带第三纪植物区系的紧密联系。(3)罗霄山脉5条山脉间区系组成呈现出明显的南北分异特征, 自北向南热带属与温带属比值逐渐增大, 北段幕阜山脉温带性成分明显占优势, 与华中区系关联密切, 而南段万洋山脉、诸广山脉热带性属较占优势, 分布有丰富的华南区系成分。罗霄山脉地区是重要的区系交流通道, 历史时期的气候波动是本地区现代区系分布格局形成的主要原因。  相似文献   

9.
蜣螂对灵芝发酵菌丝体生长和三萜产物形成的影响   总被引:2,自引:2,他引:0  
研究了几种药用昆虫对灵芝深层培养过程中细胞生长和三萜产物形成的影响。结果表明,添加不同药用昆虫对灵芝细胞生长和细胞内三萜的形成无显著促进作用(P>0.05),但蜣螂虫粉的添加,能显著促进灵芝胞外三萜的形成(P<0.01)。在添加浓度为5g/L时,胞外三萜的产量从对照的220.2±9.7mg/L提高到304.3±11.8mg/L。结果提示药用昆虫蜣螂虫粉中含有促进灵芝胞外三萜形成的功能因子。  相似文献   

10.
Variation in leaf blade, petiole and primary stem resins, composed of sesquiterpene hydrocarbons, is analysed in two contrasting species of the tropical legume Hymenaea. Five populations of the New World H. courbaril, spanning a wide range of ecosystems, are compared with a population of the disjunct African H. verrucosa. Resins in petiole and primary stem tissue are similar, but differ significantly in total composition from leaf blade tissues. The major components, caryophyllene, - and β-selinene and β-copaene vary most significantly among the tissues, but all compounds vary at highly significant levels among populations. The variation patterns in resin composition among the leaf blade and petiole/primary stem tissues are put into a larger context of comparison with the primarily diterpenoid patterns in secondary stem and pod tissues. Although the comparatively minor quantitative differences in the sesquiterpene systems could be attributed solely to developmental and physiological differences among the tissues and populations, the total weight of accumulating evidence regarding quantitative variation and demonstrated toxic and deterrent properties of sesquiterpene resins to insect herbivores leads us to hypothesize a possible role of differential predator pressures.  相似文献   

11.
云南高原地区是一个十分自然的植物区系地区,其种子植物区系约有5545种,隶属于1491属和 249科中,基本上是亚热带性质。本地区水平及垂直替代现象明显,地理联系广泛,但与中国-喜马拉雅亚区不同区系地区联系密切,显然是中国-喜马拉雅区系成分的发源地。根据特有种丰富程度以及一些自然地理特征,云南高原地区在区系上可以划分为3个小区:滇中高原小区、澜沧红河中游小区和滇东南小区,它们之间在许多方面有明显差异,其原因可能由于不同地史背景。  相似文献   

12.
Celahypodiol 1, an unusual 17-membered carbon diterpenoid with a novel skeleton, and a new triterpenoid 12-oleanene-3beta,6alpha-diol 2, together with four known compounds furreginol 3, suigol 4, 20(30)-lupene-3beta, 29-diol 5, and 20(29)-lupene-1beta,3beta-diol 6, were isolated from the stalks of Celastrus hypoleucus (Oliv.) Warb. Their structures were established by means of spectroscopic analysis, including 2D NMR. The new compounds exhibited anti-tumor activities against a panel of human tumor cell lines.  相似文献   

13.
14.
In this brief review on Koji Nakanishi's remarkable career in natural products chemistry, we have highlighted a number of his accomplishments that illustrate the broad diversity of his interests. These include the isolation, structure determination, and biological mechanism of action of many natural products including the triterpenoid pristimerin; the diterpenoid ginkgolides; insect and crustacean molting hormones; phytoalexins; the toxic red tide principle brevetoxin; the vanadium tunicate pigments; philanthotoxin from killer wasps; antisickling agents; mitomycin DNA adducts; insect antifeedants; a mitotic hormone, the small molecule fish attractants from the sea anemone; new isolation and purification technologies; molecular chemistry of vision; age-related macular degeneration; and the development of the exciton circular dichroism (CD) chirality method for microscale determination of absolute configuration of natural products and chirality of other chiral molecules and supramolecular assembly.  相似文献   

15.
Abstract.  Phylogenetic relationships among Heliconiinae genera are proposed based on early-stage and adult morphology. Parsimony analyses of forty-nine species in twenty-nine genera indicate that Heliconiinae can be divided into four main groups: (1) Pardopsis , Acraea and Actinote ; (2) Cethosia plus Neotropical genera; (3) Oriental genera and (4) fritillaries. Analyses of adult characters suggested that Oriental genera form a monophyletic group, whereas those of adult plus early-stage characters artificially split this group into three separate lineages. Our character set does not contain enough phylogenetic information to resolve relationships among fritillary genera with confidence, and further studies of this group are needed. The classification of the Heliconiinae is revised based on our results.  相似文献   

16.
天津市种子植物区系成分分析   总被引:5,自引:0,他引:5  
沙汀  张文辉  刘新成 《植物研究》2009,29(1):96-102
天津市共有种子植物1 471种(含种下等级),隶属于720属140科,其中裸子植物7科、10属、16种;被子植物133科、710属、1 455种。另外,具有中国特有属11属。通过对天津种子植物区系的组成、地理成分、区系特征进行分析,得出主要结论如下:种子植物较丰富;植物区系起源古老,但也具有年轻性;区系成分复杂,特别是北温带成分占优势,但是在温带地区内有大比例的热带、亚热带属种的出现,说明本植物区系有着更为喜暖的祖先;多种区系成分汇集,与周邻联系广泛,地理成分以华北成分为主。  相似文献   

17.
This review summarizes the flavonoids isolated from three genera, namely, Aconitum, Delphinium, and Consolida, belonging to tribe Delphineae in the Ranunculaceae family for the first time. A total of 104 distinct flavonoid components, including 85 flavonols, 13 anthocyanins, four flavones, and two neoflavones, have been isolated from 44 members of tribe Delphineae. Flavonols account for the largest proportion and can be regarded as the dominant group of flavonoids in this tribe. Of the 104 isolated flavonoids, 55 are novel, indicating the high chemical diversity among the flavonoid constituents of Delphineae plants. Flavonoids in Delphineae plants exhibit chemotaxonomic significance, characterizing certain Delphineae species well. Flavonol glycosides, as the major flavonoid constituents in the investigated Delphineae species, could also serve as valuable chemotaxonomic markers in addition to diterpenoid alkaloids for the identification of Delphineae species.  相似文献   

18.
Polymeric materials are often used in pharmaceutical packaging, delivery systems, and manufacturing components. There is continued concern that chemical entities from polymeric components may leach into various dosage forms, particularly those that are comprised of liquids such as parenterals, injectables, ophthalmics, and inhalation products. In some cases, polymeric components are subjected to routine extractables testing as a control measure. To reduce the risk of discovering leachables during stability studies late in the development process, or components that may fail extractables release criteria, it is proposed that extractables testing on polymer resins may be useful as a screening tool. Two studies have been performed to evaluate whether the extractables profile generated from a polymer resin is representative of the extractables profile of components made from that same resin. The ELSIE Consortium pilot program examined polyvinyl chloride and polyethylene, and another study evaluated polypropylene and a copolymer of polycarbonate and acrylonitrile butadiene styrene. The test materials were comprised of polymer resin and processed resin or molded components. Volatile, semi-volatile, and nonvolatile chemical profiles were evaluated after headspace sampling and extraction with solvents of varying polarity and pH. The findings from these studies indicate that there may or may not be differences between extractables profiles obtained from resins and processed forms of the resin depending on the type of material, the compounds of interest, and extraction conditions used. Extractables testing of polymer resins is useful for material screening and in certain situations may replace routine component testing.KEY WORDS: extractables, PC/ABS, polyethylene, polypropylene, polyvinylchloride  相似文献   

19.
Diterpenoid alkaloids exhibit remarkable chemical properties and biological activities. Such compounds are frequently found in plants of the genera Aconitum, Delphinium, and Garrya. Several diterpenoid alkaloid components from Delphinium elatum cv. Pacific Giant and their derivatives exhibited cytotoxic activity against lung, prostate, nasopharyngeal, and vincristine-resistant nasopharyngeal cancer cell lines. Phytochemical investigations on the seeds of D. elatum cv. Pacific Giant led to the isolation of four new C19-diterpenoid alkaloids, melpheline (1), 19-oxoisodelpheline (2), N-deethyl-19-oxoisodelpheline (3), and N-deethyl-19-oxodelpheline (4). The isolated alkaloids were elucidated by extensive spectroscopic methods including NMR (1D and 2D), IR, and MS (HRMS).  相似文献   

20.
22 kinds of seed oils were extracted from 8 genera of the family Ulmaceae in China The seed oils were examined for their characteristics and fatty acid compositions by gas liquid chromatography. The fatty acid compositions of these oils were found to fall into two classes. Some genera (such as Ulmus, Zelkova) contain mainly lower saturated acids, in which the chief acid is capric acid 10:0, while the genera (such as Celtis, Pteroceltis, Aphananthe, Trema, Gironniera) contain mainly unsaturated acids, in which the chief acid is linoleic acid 18:2. Hemiptelea davidii (Hance) Planch contain however either certain amount of short-chain saturated acids or higher unsaturated acids, it appears a intermediate genus between the two classes. According to the component acids we support that the Ulmaceae be split into two subfamilies. The genera arrangement based on the component acids corresponds basically with the view based on mophological characters and flavonoids found in leaves of Ulmaceae, but there are some discrepancies in certain genera, for example, the Aphananthe should beplaced in Celtoid instead of Ulmoid by the present study.  相似文献   

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