109 resultados para Meconopsis integrifolia


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青藏高原是我国植物多样性和特有性最高的地区,其中横断山区由于复杂的地质变迁历史和独特的地貌已成为研究物种多样性的一个热点。全缘叶绿绒蒿是分布于青藏高原及其周边地区的高山植物,该物种的谱系生物地理学研究不仅有助于揭示横断山区的物种分化机制及地理分布格局的形成过程,而且有助于探讨青藏高原隆升及新生代晚期气候变化对横断山区物种遗传结构的影响。 本研究对全缘叶绿绒蒿的12 个群体、153 个个体的叶绿体DNA trnS-trnfM片段进行了序列测定,比对校正后该片段的长度为877-962 bp,其中含6 个突变位点和5 个插入缺失(两个7 bp,两个39 bp,一个6 bp)。根据这些变异,可分为12 种叶绿体单倍型(H1-H12)。全缘叶绿绒蒿在物种水平上的核苷酸多态性分别为π = 0.00152 和θ = 0.00122,单倍型多样性为HE 为0.791,群体之间的遗传分化系数FST 为0.46579。中性检测结果显示无论在物种水平还是在群体水平,都没有显著偏离中性模式,说明该物种近期没有经历明显的瓶颈效应或奠基者效应等历史事件。我们从地理上将全缘叶绿绒蒿的群体分为四个地区,即云南、川西、川北和青海地区。AMOVA 分析显示群体间的遗传分化系数FST为0.46579,大多数的核苷酸多态性来自群体内(53.42%),其次来自于地区内的群体间(40.44%),而四个地区之间的分化非常小,仅占6.14%。失配分析显示在整个物种的分布范围内呈现单峰式样(r = 0.0475, P = 0.07924),这种分布虽然是不显著的,但P 值接近显著的临界,说明可能存在不明显的扩散,但在各个地区内的群体都没有扩散的迹象。 比较单倍型的地理分布和单倍型之间的进化关系,发现川西和川北地区存在明显差异,这两个地区都拥有比较古老的单倍型,也具有地区特异的稀有单倍型,因此很可能是全缘叶绿绒蒿在冰期时的避难所。云南地区只具有一个古老单倍型H1,这种分布可能是由川西和川北避难所的南迁造成的,也可能该地区自身就是古老单倍型H1 的发源地。青海地区只有两种古老的单倍型,由于冰期后物种有往高纬度迁移的趋势,因此这个地区的单倍型可能是在冰期后由川西和川北迁移过去的。全缘叶绿绒蒿在横断山区单倍型的片段化分布及多个避难所的存在可能与该地区独特的高山低谷相间地貌以及受多次冰期影响有密切关系。

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本论文由四章组成,第一、二、三章为实验论文,分别报道了中药羌活、菊花、全缘叶绿绒蒿的化学成分的高效液相色谱(HPLC)和液相色谱-质谱(LC-MS)联用分析以及挥发油的气相色谱-质谱(GC-MS)联用分析。第四章概述了重要藏药材化学成分的研究进展。 第一章首先对28批不同产地的羌活药材进行了HPLC分析,建立了羌活的指纹图谱。结果表明,不同产地羌活的化学成分基本相似,但是各组分在含量上存在较大差异。其次,对羌活的主要化学组分包括紫花前胡苷、紫花前胡素、6'-O-反式阿魏酸紫花前胡苷、茴香酸对羟基苯乙酯、羌活醇和异欧前胡素进行了定量分析。此外,针对同一产地不同采集时间的羌活挥发油进行系统分析,结果表明它们的化学成分基本相似,主要含有a-蒎烯、b-蒎烯、柠檬烯和龙脑乙酸酯等,只是各组分含量有所变化,这说明采集药材时要注意采集时间。 第二章分别报道了不同产地不同品种菊花非挥发性成分的液相色谱-二极管阵列检测-串联质谱(LC-PDA-MSn)分析和挥发性成分的气相色谱-质谱(GC-MS)联用分析比较。首先通过液相色谱-质谱-串联质谱对各色谱峰进行定性分析,通过与标准品对照,以及UV和MSn提供的结构信息,结合文献报道共鉴定了11个化学成分,包括绿原酸和10个黄酮化合物,并比较了不同品种菊花的化学成分相同之处和不同之处。另外,对七种不同品种不同产地的菊花挥发性成分通过GC-MS分析表明其主要挥发性成分为单萜类、倍半萜类化合物,共有成分樟脑、龙脑和龙脑乙酸酯等,各成分在不同挥发油中的含量变化明显。 第三章为藏药全缘叶绿绒蒿不同部位挥发油成分的气相色谱-质谱(GC-MS)联用分析,比较其挥发油化学成分及其含量变化的异同点。研究结果表明,全缘叶绿绒蒿花精油的化学成分明显多于全草部位,且两者主要成分有较大的差别。 第四章综述了青藏高原重要藏药材化学成分的研究进展。分别对藏药的资源特色和110多种常用重要藏药材的化学成分的研究情况以及藏药未来发展思路进行了阐述,以期对相关的研究提供一些信息。 This dissertation consists of four parts. The first part reports studies on the fingerprint of Notopterygium incisum and N. forbesii by HPLC-PDA-MSn, and on the constitutents of essential oil by GC-MS. The second part elaborates the chemical constitutents of Chrysanthemum L. by LC-MS and GC-MS analysis. The third part reports the chemical compositions of the essential oil from the different parts of Meconopsis integrifolia. The fourth part reviews on the progress of the studies on the chemical constitutents in Tibetan medicines. The first chapter is about HPLC analysis of a traditional Chinese herbal medicine Qiang-huo (Notopterygium incisum and N. forbesii ). Firstly, based on analyzing and contrasting the relative retention time and relative paek area in chromatographic fingerprint, the HPLC chromatographic fingerprint of Notopterygium incisum was established, which can used as a scientific basement for the quality evalution of this herb. Secondly, quantitative analysis were performed on the main chemical constitutents of Notopterygium incisum and N. forbesii including nodakenin, nodakenetin, 6’-O-trans-feruloylnodakenin, p-hydroxypenethylanisate, notopterol and isoimperatorin. The results indicated that the contents were variable related to different growth regions. Lastly, the essential oil of Notopterygium incisum collected in different harvest times is analyzed by GC-MS. The second chapter is about HPLC-MS and GC-MS analysis of several species of Chrysanthemum L. Firstly, eleven compounds including chlorogenic acid and ten flavone compounds were identified in the methanol extract of Chrysanthemum morifolium Ramat. from different regions by HPLC-MS analysis. Secondly, the essential oil of seven different species of Chrysanthemum L.were extracted by steam distillation, and its compositions were isolated and identified by GC-MS. The main active constitutents such as camphor, borneol and bornyl acetate were detected, but the relative content varied notably. The third chapter is about GC-MS analysis of the essential oil from different parts of Meconopsis integrifolia. It indicated great difference of the chemical compositions of their oil in the flowers and residual overground part. The last chapter is a review of the research progress of the Tibetan medicines, which includes their features and their main chemical constitutents.

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Habitat models are widely used in ecology, however there are relatively few studies of rare species, primarily because of a paucity of survey records and lack of robust means of assessing accuracy of modelled spatial predictions. We investigated the potential of compiled ecological data in developing habitat models for Macadamia integrifolia, a vulnerable mid-stratum tree endemic to lowland subtropical rainforests of southeast Queensland, Australia. We compared performance of two binomial models—Classification and Regression Trees (CART) and Generalised Additive Models (GAM)—with Maximum Entropy (MAXENT) models developed from (i) presence records and available absence data and (ii) developed using presence records and background data. The GAM model was the best performer across the range of evaluation measures employed, however all models were assessed as potentially useful for informing in situ conservation of M. integrifolia, A significant loss in the amount of M. integrifolia habitat has occurred (p < 0.05), with only 37% of former habitat (pre-clearing) remaining in 2003. Remnant patches are significantly smaller, have larger edge-to-area ratios and are more isolated from each other compared to pre-clearing configurations (p < 0.05). Whilst the network of suitable habitat patches is still largely intact, there are numerous smaller patches that are more isolated in the contemporary landscape compared with their connectedness before clearing. These results suggest that in situ conservation of M. integrifolia may be best achieved through a landscape approach that considers the relative contribution of small remnant habitat fragments to the species as a whole, as facilitating connectivity among the entire network of habitat patches.

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The Black Rat (Rattus rattus), a global pest within the macadamia production industry, causes up to 30% crop damage in Australian orchards. During early stages of production in Australia, research demonstrated the importance of non crop adjacent habitats as significant in affecting the patterns of crop damage seen throughout orchards. Where once rodent damage was limited to the outside edges of orchard blocks, growers are now reporting finding crop damage throughout entire orchards. This study therefore aims to explore the spatial patterns of rodent distribution and damage now occurring in Australian macadamia orchards. We show that rodent damage and rodent distribution in these newer production regions differ from that shown in previous Australian research. Previous Australian research has shown damage patterns which were associated with the edges of orchard blocks however this study demonstrates a more widespread damage distribution. In the current study there is no relationship between rodent damage and the orchard edge. Arboreal rodent nests were identified within these newer orchard systems, suggesting rodents are residing within the tree component of the orchard system and not dependent on adjacent non-crop habitat for shelter. Results from this study confirm that rodents have modified their nesting and foraging behaviour in newer orchards systems in Australia. We suggest that this is a response of increased and prolonged availability of macadamia nuts in newer production regions enabling populations to be maintained throughout the year. Management strategies will require modification if control is to be achieved.

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Jacalin and artocarpin, the two lectins from jackfruit (Artocarpus integrifolia) seeds, have different physicochemical properties and carbohydrate-binding specificities. However, comparison of the partial amino-acid sequence of artocarpin with the known sequence of jacalin indicates close to 50% sequence identity. Artocarpin crystallizes in two forms, both monoclinic P2(1), with one and two tetramic molecules, respectively, in the asymmetric units of form I (a = 69.9, b = 73.7, c = 60.6 Angstrom and beta = 95.1 degrees) and form II (a = 87.6, b = 72.2, c = 92.6 Angstrom and beta = 101.1 degrees). Both the crystal structures have been solved by the molecular replacement method using the known structure of jacalin as the search model and ope of them partially refined, confirming that the two lectins are indeed homologous.

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Jacalin [Artocarpus integrifolia (jack fruit) agglutinin] is made up of two types of chains, heavy and light, with M(r) values of 16,200 +/- 1200 and 2090 +/- 300 respectively (on the basis of gel-permeation chromatography under denaturing conditions). Its complete amino acid sequence was determined by manual degradation using a 4-dimethylaminoazobenzene 4'-isothiocyanate double-coupling method. Peptide fragments for sequence analysis were obtained by chemical cleavages of the heavy chain with CNBr, hydroxylamine hydrochloride and iodosobenzoic acid and enzymic cleavage with Staphylococcus aureus proteinase. The peptides were purified by a combination gel-permeation and reverse-phase chromatography. The light chains, being only 20 residues long, could be sequenced without fragmentation. Amino acid analyses and carboxypeptidase-Y-digestion C-terminal analyses of the subunits provided supportive evidence for their sequence. Computer-assisted alignment of the jacalin heavy-chain sequence failed to show sequence similarity to that of any lectin for which the complete sequence is known. Analyses of the sequence showed the presence of an internal repeat spanning residues 7-64 and 76-130. The internal repeat was found to be statistically significant.

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Four new crystal forms of the anti-T lectin from jackfruit (Artocarpus integrifolia) have been prepared and characterized. Three of them, two monoclinic (P21, A = 59·4 Å, B = 83·3 Å, C = 63·5 Å, β = 107·7°; C2, A = 106·1,Å, B = 53·9 Å, C = 128·0 Å, β = 95·0 Å) and one orthorhombic (C2221, A = 98·1 Å, B = 67·3 Å, C = 95·1 Å) were grown with 2-methylpentan-2,4-diol (MPD) as the precipitant while the fourth, an hexagonal from (P6122, A = b = 129·6 Å, C = 157·9 Å), was obtained in the presence of methyl-ga-Image -galactopyranoside with polyethylene glycol 4000 as the precipitant. The reported relative molecular mass (Mr) of the lectin was found to be inconsistent with the solvent content of the crystals estimated using measured densities. The Mr was redetermined using size-exclusion chromatography in the presence of methyl-α-Image -galactopyranoside and Ferguson-plot analysis of mobilities in polyacrylamide gel electrophoresis. The redetermined Mr (66,000) is consistent with the measured crystal densities. The orthorhombic and the hexagonal forms, which have one half molecule and one molecule, respectively, in the asymmetric unit, are suitable for high-resolution X-ray analysis.

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Artocarpin, a mannose-specific lectin, is a homotetrameric protein (M(r) 65,000) devoid of covalently attached carbohydrates and consists of four isolectins with pI in the range 5-6.5. Investigations of its carbohydrate binding specificity reveal that among monosaccharides, mannose is preferred over glucose. Among mannooligosaccharides, mannotriose (Man alpha 1-3[Man alpha 1-6]Man) and mannopentaose are the strongest ligands followed by Man alpha 1-3Man. Extension of these ligands by GlcNAc at the reducing ends of mannooligosaccharides tested remarkably improves their inhibitory potencies, while substitution of both the alpha 1-3 and alpha 1-6 mannosyl residues of mannotriose and the core pentasaccharide of N-linked glycans (Man alpha 1-3[Man alpha 1-6]Man beta 1-4GlcNAc beta 1-4GlcNAc) by GlcNAc or N-acetyllactosamine in beta 1-2 linkage diminishes their inhibitory potencies. Sialylated oligosaccharides are non-inhibitory. Moreover, the substitution of either alpha 1-3 or alpha 1-6 linked mannosyl residues of M5Gn or both by mannose in alpha 1-2 linkage leads to a considerable reduction of their inhibitory power. Addition of a xylose residue in beta 1-2 linkage to the core pentasaccharide improves the inhibitory activity. Considering the fact that artocarpin has the strongest affinity for the xylose containing hepasaccharide from horseradish peroxidase, which differs significantly from all the mannose/glucose-specific lectins, it should prove a useful tool for the isolation and characterization of glycoproteins displaying such structure.

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Thermodynamic analysis of carbohydrate binding by Artocarpus integrifolia (jackfruit) agglutinin (jacalin) shows that, among monosaccharides, Me alpha GalNAc (methyl-alpha-N-acetylgalactosamine) is the strongest binding ligand. Despite its strong affinity for Me alpha GalNAc and Me alpha Gal, the lectin binds very poorly when Gal and GalNAc are in alpha-linkage with other sugars such as in A- and B-blood-group trisaccharides, Gal alpha 1-3Gal and Gal alpha 1-4Gal. These binding properties are explained by considering the thermodynamic parameters in conjunction with the minimum energy conformations of these sugars. It binds to Gal beta 1-3GalNAc alpha Me with 2800-fold stronger affinity over Gal beta 1-3GalNAc beta Me. It does not bind to asialo-GM1 (monosialoganglioside) oligosaccharide. Moreover, it binds to Gal beta 1-3GalNAc alpha Ser, the authentic T (Thomsen-Friedenreich)-antigen, with about 2.5-fold greater affinity as compared with Gal beta 1-3GalNAc. Asialoglycophorin A was found to be about 169,333 times stronger an inhibitor than Gal beta 1-3GalNAc. The present study thus reveals the exquisite specificity of A. integrifolia lectin for the T-antigen. Appreciable binding of disaccharides Glc beta 1-3GalNAc and GlcNAc beta 1-3Gal and the very poor binding of beta-linked disaccharides, which instead of Gal and GalNAc contain other sugars at the reducing end, underscore the important contribution made by Gal and GalNAc at the reducing end for recognition by the lectin. The ligand-structure-dependent alterations of the c.d. spectrum in the tertiary structural region of the protein allows the placement of various sugar units in the combining region of the lectin. These studies suggest that the primary subsite (subsite A) can accommodate only Gal or GalNAc or alpha-linked Gal or GalNAc, whereas the secondary subsite (subsite B) can associate either with GalNAc beta Me or Gal beta Me. Considering these factors a likely arrangement for various disaccharides in the binding site of the lectin is proposed. Its exquisite specificity for the authentic T-antigen, Gal beta 1-3GalNAc alpha Ser, together with its virtual non-binding to A- and B-blood-group antigens, Gal beta 1-3GalNAc beta Me and asialo-GM1 should make A. integrifolia lectin a valuable probe for monitoring the expression of T-antigen on cell surfaces.

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Binding of 13C-labeled N-acetylgalactosamine (13C-GalNAc) and N-trifluoroacetylgalactosamine (19F-GalNAc) to Artocarpus integrifolia agglutinin has been studied using 13C and 19F nuclear magnetic resonance spectroscopy, respectively. Binding of these saccharides resulted in broadening of the resonances, and no change in chemical shift was observed, suggesting that the alpha- and beta-anomers of 13C-GalNAc and 19F-GalNAc experience a magnetically equivalent environment in the lectin combining site. The alpha- and beta-anomers of 13C-GalNAc and 19F-GalNAc were found to be in slow exchange between free and protein bound states. Binding of 13C-GalNAc was studied as a function of temperature. From the temperature dependence of the line broadening, the thermodynamic and kinetic parameters were evaluated. The association rate constants obtained for the alpha-anomers of 13C-GalNAc and 19F-GalNAc (k+1 = 1.01 x 10(5) M-1.s-1 and 0.698 x 10(5) M-1.s-1, respectively) are in close agreement with those obtained for the corresponding beta-anomers (k+1 = 0.95 x 10(5) M-1.s-1 and 0.65 x 10(5) M-1.s-1, respectively), suggesting that the two anomers bind to the lectin by a similar mechanism. In addition these values are several orders of magnitude slower than those obtained for diffusion controlled processes. The dissociation rate constants obtained are 49.9, 56.9, 42, and 43 s-1, respectively, for the alpha- and beta-anomers of 13C-GalNAc and 19F-GalNAc. A two-step mechanism has been proposed for the interaction of 13C-GalNAc and 19F-GalNAc with A. integrifolia lectin in view of the slow association rates and high activation entropies. The thermodynamic parameters obtained for the association and dissociation reactions suggest that the binding process is entropically favored and that there is a small enthalpic contribution.

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Com o objetivo de conhecer a fenologia da floração da nogueira macadâmia, foram efetuadas observações, durante o período de maio de 1993 a outubro de 1995, em plantas do pomar da FCAV-UNESP, Jaboticabal, São Paulo, Brasil (latitude 21º 15'S, longitude 48º 18'W). Foram utilizadas plantas de 6 anos de idade, das cultivares IAC 5-10 e IAC 8-17, selecionadas no Brasil. Verificou-se que o período de intumescimento das gemas florais ocorreu a partir de maio. As gemas florais são mistas e localizam-se principalmente em ramos finos (0,2 a 0,7 cm). Das três gemas existentes na axila foliar, a gema superior e a mediana geralmente originam inflorescências. O período ocorrido entre o início de crescimento da gema floral e a antese foi de 48 a 55 dias ou 330 a 350 graus-dia (temperatura-base = 12,8 ºC). A inflorescência e a flor + pedicelo apresentaram um padrão de crescimento do tipo sigmoidal simples. O período de flores em antese concentrou-se entre meados de agosto e meados de setembro.

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O presente trabalho teve como objetivo, verificar o tempo de armazenamento necessário para que seja atingida a viabilidade máxima e o tempo de embebição máxima de sementes de macadâmia (Macadamia integrifolia Maiden & Betche var. IAC-4-20). As sementes foram pesadas e colocadas em recipientes com água para que ocorresse o processo da embebição, sendo realizada a pesagem a cada 6 horas. Pode-se concluir que a embebição foi máxima ao redor de 90 horas após o início da embebição. Para a análise da viabilidade das sementes, estas foram semeadas mensalmente, durante 12 meses a partir da colheita. Verificou-se que a viabilidade máxima das sementes é atingida, 4 meses após o início do armazenamento.

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Stem diameter in Gallesia integrifolia (Spreng.) Harms (Phytolaccaceae) increases by forming concentric rings of xylem alternating with phloem, which show frequent anastomoses. After a period of primary growth and the formation of first (normal) ring of vascular cambium, further successive rings are initiated outside this cambium. The second ring of cambium originates from the pericycle parenchyma located between the proto-phloem, and the pericycle fibres. Each cambium produces centripetally secondary xylem and centrifugally secondary phloem. Differentiation of xylem precedes that of phloem and the first elements formed are always xylem fibres. Structurally, the vascular cylinder is composed by successive rings of secondary xylem and phloem. These rings are separated by wide bands of conjunctive parenchyma tissue. Presence of collateral vascular bundles with irregular orientation is observed in the region of anastomoses of two or more bands of conjunctive tissue. These bundles are surrounded by isodiametric, lignified and thick-walled cells. In some of the cambial rings, occurrence of polycentric rays was also noticed; these rays are tall, and characterized by the presence of meristematic regions that differentiated into thick-walled elements of secondary xylem. Origin and development of the successive cambia and the structure of xylem are discussed.