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1.
深裂黄草乌二萜生物碱研究   总被引:3,自引:0,他引:3  
深裂黄草乌(Aconitum vilmorinianum var.altifidum W. T.Wang)又名西南乌头、紫乌头、藤乌,主要分布于云南东北部、贵州西部和四川西部(泸定、天全)海拔2800m的山地。块根可祛风散寒、除湿止痛,民间也用于解乌头中毒。其化学成分未见报道。本文从深裂黄草乌全草中分离鉴定了3个二萜生物碱,一个为C-19骨架类型,两个为C-20骨架类型。其中一个为新化合物,是C-20骨架类型二萜生物碱,命名为深裂黄草乌碱vilmorinianine(Ⅰ),另两个化合物是denudatine(Ⅱ)和deoxyaconitine(Ⅲ),均首次从该植物中得到。  相似文献   

2.
The gonadosomatic index and gonad mean weight of Sardinella maderensis off the west coast of Cameroon were used to assess their reproductive patterns. Results showed that first maturity is at about 17 cm total length, and is the same for both males and females. S. maderensis breeds continuously but with two spawning peaks, a major one from April to July and a minor one from December to January.
Réumé
Reproduction des Sardinella maderensis sur la côte ouest du Cameroun
L'indice gonadosomatique et le poids moyen des gonades ont été utilisés pour évaluer les schimas de reproduction des Sardinella maderensis (Clupeidés) dans une étude menée sur la côte ouest du Cameroun. Dapres les risultats obtenus, la taille de premiére maturité est identique chez les msàles et chez les femelles (de l'ordre de 17 cm de longueur totale). S. maderensis se reproduit continuellement avec deux piriodes de grande ponte, I'une d'avril sà juillet et l'autre, moins importante, de décembre sà janvier.

Zusammenfassung


Reproduktionsmodus von Sardinella maderensis an der Westküste won Kamerun
Der gonado-somatische Index und das mittlere Gonadengewicht wurden zur Beurteilung des Repro-duktionsmodus von Sardinella maderensis an der Westküste von Kamerun herangezogen. Die Ergeb-nisse zeigen, daß die Länge der Erstlaicher sowohl für Weibchen als auch für Männchen bei etwa 17 cm Totallänge liegt. S. maderensis laicht kontinuierlich, mit zwei ausgeprägten Spitzen: eine Hauptlaichpe-riode zwischen April und Juli und eine schwächer ausgeprägte zwischen Dezember und Januar.  相似文献   

3.
The gobiid fishes of temperate Macaronesia (eastern Atlantic)   总被引:1,自引:0,他引:1  
  相似文献   

4.
Evolution of three Canary Island Vespertilionid bat species, Pipistrellus kuhlii, Pipistrellus maderensis, and Hypsugo savii was studied by comparison of approximately 1 kbp of mtDNA (from cytochrome b and 16S rRNA genes) between islands. mtDNA reveals that both P. kuhlii and P. maderensis exist in sympatry on Tenerife (and possibly other islands). Their morphological similarity explains why their co-occurrence had not been detected previously. Levels of sequence divergence are quite low within P. maderensis. Haplotypes were either identical or separated by /=12 mutational steps) indicating colonization of the latter from the former sometime during the last approximately 1.2 Ma, with low subsequent gene flow. Unlike P. maderensis the El Hierro population alone appears to represent an ESU. The H. savii haplotypes detected in Gran Canaria and Tenerife are identical or separated by 1 mutational step.  相似文献   

5.
Lipid content and fatty acid composition were determined in three species of edible fish caught in Senegalese waters during the upwelling season (January, 1993). Sardinella maderensis and Sardinella aurita are fat fish containing more than 5% (fresh wt.) of lipids, whereas Cephalopholis taeniops is a lean fish with approximately 1% of lipids. Skin, liver and muscle were studied for each fish species. About 40 fatty acids were identified by GC and GC/MS as methyl esters and N-acyl pyrrolidides. Palmitic acid was the main acid in the muscle and skin of all samples studied (20-33% of total fatty acids). Oleic acid was the main fatty acid in the liver of S. maderensis (27.2%+/-0.1) and S. aurita (44.7%+/-0.1). Arachidonic acid was a minor component in all samples. The flesh (muscle) of the three fish species contained high concentrations of omega3 polyunsaturated fatty acids (PUFA), ranging from 16.0 to 29.1% and including 20:5 omega3 (eicosapentaenoic acid, EPA) and 22:6 omega3 (docosahexaenoic acid, DHA) acids as major components. These two acids together accounted for 24.7%+/-0.1 and 12.9%+/-0.1 of total acids in the skin of S. maderensis and S. aurita, respectively. The percentages of PUFA found in the fish studied were very similar to those in fish used commercially as sources of PUFA. Muscle sterols, which accounted for 9-11% of total lipids, consisted mainly of cholesterol (up to 97% of total sterols).  相似文献   

6.
Frölich C  Hartmann T  Ober D 《Phytochemistry》2006,67(14):1493-1502
Phalaenopsis hybrids contain two 1,2-saturated pyrrolizidine monoesters, T-phalaenopsine (necine base trachelanthamidine) and its stereoisomer Is-phalaenopsine (necine base isoretronecanol). T-Phalaenopsine is the major alkaloid accounting for more than 90% of total alkaloid. About equal amounts of alkaloid were genuinely present as free base and its N-oxide. The structures were confirmed by GC-MS. The quantitative distribution of phalaenopsine in various organs and tissues of vegetative rosette plants and flowering plants revealed alkaloid in all tissues. The highest concentrations were found in young and developing tissues (e.g., root tips and young leaves), peripheral tissues (e.g., of flower stalks) and reproductive organs (flower buds and flowers). Within flowers, parts that usually attract insect visitors (e.g., labellum with colorful crests as well as column and pollinia) show the highest alkaloid levels. Tracer feeding experiments with (14)C-labeled putrecine revealed that in rosette plants the aerial roots were the sites of phalaenopsine biosynthesis. However active biosynthesis was only observed in roots still attached to the plant but not in excised roots. There is a slow but substantial translocation of newly synthesized alkaloid from the roots to other plant organs. A long-term tracer experiment revealed that phalaenopsine shows neither turnover nor degradation. The results are discussed in the context of a polyphyletic molecular origin of the biosynthetic pathways of pyrrolizidine alkaloids in various scattered angiosperm taxa. The ecological role of the so called non-toxic 1,2-saturated pyrrolizidine alkaloids is discussed in comparison to the pro-toxic 1,2-unsaturated pyrrolizidine alkaloids. Evidence from the plant-insect interphase is presented indicating a substantial role of the 1,2-saturated alkaloids in plant and insect defense.  相似文献   

7.
In the course of our examination for the alkaloid productivities of Streptomyces strains, Streptomyces sp. NA–15 was found to produce a new alkaloid, pyrindicin, in the culture medium. The strain NA–15 was found to be a variant of Streptomyces griseoflavus and was designated as S. griseoflavus var. pyr indie us nov. var.

After the culture conditions for pyrindicin production were studied, pyrindicin was obtained as its hydrochloride (mp 145°C, decomp.) from the cultured broth. The compound was shown to possess weak antimicrobial and several pharmacological activities. The LD50 of the hydrochloride (ip, in mice) was 87 mg/kg.  相似文献   

8.
Specimens of the spongivorous Mediterranean opisthobranch Tylodina perversa that had been collected while feeding on Aplysina acerophoba were shown to sequester the brominated isoxazoline alkaloids of their prey. Alkaloids were stored in the hepatopancreas, mantle tissues, and egg masses in an organ-specific manner. Surprisingly, the known sponge alkaloid aerothionin which is found only in A. cavernicola but not in A. aerophoba was also among the metabolites identified in wild caught specimens of T. perversa as well as in opisthobranchs with a documented feeding history on A. aerophoba. Mollusc derived aerothionin is postulated to be derived from a previous feeding encounter with A. cavernicola as T. perversa was found to freely feed on both Aplysina sponges in aquarium bioassays. The possible ecological significance of alkaloid sequestration by T. perversa is still unknown.  相似文献   

9.
Chloroplast (trnT-L) and nuclear rDNA (ITS) sequence analyses of the Araliaceae provide strong molecular evidence for the monophyly of the genus Hedera. Phylogenetic reconstructions suggest multiple origins and an active polyploidization process not only in the formation of tetraploids (2n = 96), hexaploids (2n = 144), and octoploids (2n = 192), but also of diploids (2n = 48). A high basic chromosome number of x = 24, extensive polyphyly in widespread diploids, and terminal placement of Hedera in phylogenies of the Araliaceae reveal that extant diploid taxa may be, in fact, assemblages of ancestral polyploids from plants of n = 12. Four major lineages containing four types of chloroplast (chlorotypes I, II, III, and IV), which are defined by different trnT-L nucleotide substitutions and two large insertions (50- and 30-bp), provide evidence for evolutionary processes and historical biogeography in Hedera. We propose a scenario where an initial colonization in the Mediterranean basin by Asian ancestors (carrying the ancestral Araliaceae chlorotype I) is followed by differentiation into the four chlorotypes of the Mediterranean region, and then recolonization of Asia and northern Europe only by chlorotype III. The Macaronesian taxa (Hedera azorica, Hedera maderensis ssp. maderensis, and Hedera canariensis) appear to have originated from a single-colonization event to each archipelago with no further contact either with continental or insular species.  相似文献   

10.

Background and Aims

Previous measurements of conifer alkaloids have revealed significant variation attributable to many sources, environmental and genetic. The present study takes a complementary and intensive, common garden approach to examine genetic variation in Pinus ponderosa var. ponderosa alkaloid production. Additionally, this study investigates the potential trade-off between seedling growth and alkaloid production, and associations between topographic/climatic variables and alkaloid production.

Methods

Piperidine alkaloids were quantified in foliage of 501 nursery seedlings grown from seed sources in west-central Washington, Oregon and California, roughly covering the western half of the native range of ponderosa pine. A nested mixed model was used to test differences among broad-scale regions and among families within regions. Alkaloid concentrations were regressed on seedling growth measurements to test metabolite allocation theory. Likewise, climate characteristics at the seed sources were also considered as explanatory variables.

Key Results

Quantitative variation from seedling to seedling was high, and regional variation exceeded variation among families. Regions along the western margin of the species range exhibited the highest alkaloid concentrations, while those further east had relatively low alkaloid levels. Qualitative variation in alkaloid profiles was low. All measures of seedling growth related negatively to alkaloid concentrations on a natural log scale; however, coefficients of determination were low. At best, annual height increment explained 19·4 % of the variation in ln(total alkaloids). Among the climate variables, temperature range showed a negative, linear association that explained 41·8 % of the variation.

Conclusions

Given the wide geographic scope of the seed sources and the uniformity of resources in the seedlings'' environment, observed differences in alkaloid concentrations are evidence for genetic regulation of alkaloid secondary metabolism in ponderosa pine. The theoretical trade-off with seedling growth appeared to be real, however slight. The climate variables provided little evidence for adaptive alkaloid variation, especially within regions.Key words: Pinus ponderosa var. ponderosa, Pinaceae, 2,6-disubstituted piperidine alkaloids, secondary products, geographic variation, progeny study, plant defense, Growth–Differentiation Balance Hypothesis, PRISM  相似文献   

11.
The genus Thymus (Lamiaceae) is represented by 38 species (64 taxa) in Turkey, and 24 of which are endemic to Turkey. Aerial parts of Thymus longicaulis subsp. chaubardii var. chaubardii, T. zygioides var. lycaonicus, T. longicaulis subsp. longicaulis var. subisophyllus and T. pulvinatus collected from three different localities in Balikesir province were subjected to hydrodistillation to yield essential oils which were subsequently analysed by GC and GC/MS. The main constituents of the oils were identified, and antimicrobial bioassay was applied. Thymol (56.6%, 42.8%, 36.9%) was the main component in the oils of T. longicaulis subsp. chaubardii var. chaubardii (chemotype I), T. longicaulis subsp. chaubardii var. chaubardii (chemotype II) and T. zygioides var. lycaonicus respectively. The oil of T. longicaulis subsp. longicaulis var. subisophyllus contained carvacrol (60.0%) and the oil of T. pulvinatus borneol (27.9%) as main constituents.  相似文献   

12.
Alkaloid profiles of two Egyptian Senecio species (Senecio aegyptius var. discoideus and S. desfontainei) in addition to a cultivated species (S. cineraria) were studied using capillary GLC and GLC-mass spectrometry with respect to pyrrolizidine alkaloids (PAs). Four alkaloids were identified in S. aegyptius var. discoideus, 8 in S. desfontainei and 13 in S. cineraria. Some of these alkaloids have not been reported from these plants. The alkaloidal pattern of different plant organs (flowers, leaves, stem, root) were also investigated. Senecionine has been found to be a one of the major alkaloid in all studied species, it was isolated and its structure was elucidated by 1H- and 13C-NMR.  相似文献   

13.
湖北菱科的数量分类研究[Ⅱ]   总被引:2,自引:0,他引:2  
引言菱科(Trapaceae)植物为一年生水生浮叶草本,常见于湖泊,池塘及沟渠中。全世界约有70余种,主要分布于旧大陆的温带、亚热带地区,亦见于热带地区,如印度,东南亚及非洲,后来被引进美洲大陆和澳大利亚。中国有5至10种及其栽培种。菱科为一单属科。自林奈时期以来,菱科的分类学研究一直是一个富有探索性的问  相似文献   

14.
延胡索亚属(Capnites DC)是紫堇属中较进化的一群,不少种类有药用价值。约57种,中国有17种,3变种,10变型。  相似文献   

15.
展毛短柄乌头中的一个新二萜生物碱   总被引:2,自引:0,他引:2  
从展毛短柄乌头(Aconitum brachypodum var.laxiflorum Fletcher et Lauener)根中分离鉴定了五个二萜生物碱,其中四个为已知成分,分别为乌头碱(aconitine)、3-去氧乌头碱(3-deoxyaconitine)、3-乙酰乌头碱(3-acetylaconitine)、雪乌碱(penduline),另一个为新成分,命名为丽鲁碱(laxiconitine),其结构通过光谱分析及化学反应测定如(1)。  相似文献   

16.
Conditions of agroclavine biosynthesis by the mutant Claviceps sp. strain s 106 were studied. The content of agroclavine was maximum (1.5-2 g/l) on days 15-16 of cultivation in the complex medium T25, containing sucrose, citric acid, and yeast extract. Agroclavine was the major component of the alkaloid fraction (90-95%). Storage of the culture at -70 degrees C in T25 supplemented by 7% glycerol provided a stable level of alkaloid formation.  相似文献   

17.
小麦染色体组的起源与进化探讨   总被引:4,自引:0,他引:4  
陈庆富   《广西植物》1997,17(3):276-282
对小麦染色体组的起源及其进化进行了全面综述后,提出了一个新的小麦进化途径,并认为:(1)Triticummonococumvarurartu是多倍体小麦A组的原初供体,在A组进入多倍体小麦后有Tmonovarboeoticum的基因渗入;(2)B和G组的原初供体是Tspeltoides的S组,在该S组进入多倍体小麦后有两个进化方向,即S组结构分化形成G组和S组经外源染色体代换及重组等而进化成B组;(3)Tturgidum和Ttimophevi都是来自Tspeltoides为母本与Tmonovarurartu杂交后并双二倍化而形成的原初四倍体小麦(SSAA),并由它分别经遗传渗入和结构分化而成;(4)Tzhukovskyi是Ttimophevi作母本与Tmonovarboeoticum杂交并双二倍化而形成,故它具有分别来自Tmonovarurartu和Tmonovarboeoticum的两类A组;(5)Taestivum的D组来自Ttauschi;(6)无论A组、B组、D组、G组在进入多倍体小麦后均有相当分化,同时在其供体种中也有一定分化。  相似文献   

18.
Fifteen new taxa of the genus Ribes L. (Saxifragaceae) are described from China. These new taxa are R. alpestre var. eglandulosum L. T. Lu, R. burejense var. villosum L. T. Lu, R. moupinense var. pubicarpum L. T. Lu, R. himalense var. pubicalycinum L. T. Lu et J. T. Pan, R. meyeri var. pubescens L. T. Lu, R. davidi var. ciliatum L. T. Lu, R. davidi var. lobatum L. T. Lu, R. laurifolium var. yunnanense L. T. Lu, R. xizangense L. T. Lu, R. glabricalycinum L. T. Lu, R. tenue var. incisum L. T. Lu, R. vilmorinii var. pubicarpum L. T. Lu, R. rubrisepalum L. T. Lu, R. glabrifolium L. T. Lu, R.fasciculatum var. guizhouense L. T. Lu.  相似文献   

19.
从蔷薇科绣线菊属植物急尖绣线菊(Spiraea japonica var.acuta Yu)的根部分离得到6个二萜生物碱,经光谱分析,其中5个来spiramines A(1),B(2),P(3)和U(4)及spiradine F(5),另一微量成分被鉴定为一新的二萜生物碱,命名为spiramine W(6)。  相似文献   

20.
从分子学角度探明维吾尔药材红豆杉的植物基原,为维吾尔药材标准化与维吾尔药产业化提供科学依据。采用试剂盒法提取红豆杉属植物及药材基因组DNA,PCR扩增ITS2片段,双向测序,应用Mega 6.0软件分析序列,计算种内及种间遗传距离,构建NJ鉴别树。红豆杉属植物ITS2序列长度为229~231bp,GC含量为59.13%~60.26%;西藏红豆杉与红豆杉及南方红豆杉种内种间K2P距离为0,与东北红豆杉、命叶红豆杉及曼地亚红豆杉种间K2P距离分别为0.012、0.013、0.015。NJ树结果表明,西藏红豆杉与红豆杉及南方红豆杉无法区分,与东北红豆杉、命叶红豆杉可区分;曼地亚红豆杉与其母本东北红豆杉聚在一起,无法区分。根据ITS2序列鉴定结果,西藏红豆杉与红豆杉、南方红豆杉可作为药材的同一基原,东北红豆杉可与曼地亚红豆杉作为同一基原,为维吾尔药材的真伪鉴别及质量标准提升提供基原鉴定依据。  相似文献   

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