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1.
    
A novel trypsin inhibitor isolated from seeds of Copaifera langsdorffii was purified to homogeneity and crystallized. Crystals suitable for X‐­ray analysis were grown using the hanging‐drop vapour‐diffusion method at 291 K in sodium acetate buffer at pH values near 4.3 using PEG 4000 as precipitant. The crystals presented symmetry compatible with the space group P41212 or P43212, with unit‐cell parameters a = b = 58.71, c = 93.75 Å, and diffracted to 1.83 Å resolution at the synchrotron source.  相似文献   

2.
    
Two new trypsin inhibitors, TDI-I and TDI-II, were purified from the seeds of the native Brazilian tree Copaifera langsdorffii (Caesalpinoideae, Leguminosae). The purification procedure involved ammonium sulfate fractionation, ion-exchange chromatography on DEAE-Sepharose, affinity chromatography on trypsin-Sepharose, and reversed-phase (RP) HPLC. RP-HPLC yielded two forms (TDI-I and TDI-II), as confirmed by isoelectric focusing, with pI values between 7.0 and 8.1. The molecular mass of the TDI forms was 24 kDa based on FPLC gel filtration on Superdex 75. Under reducing conditions in tricine SDS-PAGE the molecular masses of TDI-I and TDI-II were 12 and 10 kDa, respectively. The Ki values were 1.1 and 1.2 nM for TDI-I and TDI-II, respectively, and there was no inhibitory effect on chymotrypsin. Amino acid analysis revealed high levels of aspartic acid, glutamic acid, serine, glycine, proline, and lysine but low levels of methionine and aromatic amino acids in both inhibitors; the calculated molecular masses were 11,456 and 10,008 for TDI-I and II, respectively. Based on the N-terminal sequences of TDI-I and TDI-II, TDI-I belongs to the Kunitz family of trypsin inhibitors, whereas TDI-II showed no homology to any other protein. This observation suggests that TDI-II belongs to a new inhibitor subclass of low-molecular mass proteins in the subfamily Caesalpinoideae.  相似文献   

3.
Abstract

Copaifera langsdorffii Desf. has been used in the traditional medicine of Brazil for centuries to treat a wide range of conditions, including infections, wounds and inflammation. The aim of this study is to compare the effects of C. langsdorffii bark oleoresin and a methanolic extract of the fruit for their anti-Helicobacter pylori (HP) activity and gastroprotective effects. We analyzed the in vitro anti-HP activity against three HP strains: CCUG 39500 (cagA+) and two clinical isolates, G21 and 10?K (cagA?+?and cagA–, respectively). The effect of C. langsdorffii products on IL-6 release in lipopolysaccharide-stimulated human peripheral blood mononuclear cells was also evaluated. Finally, the toxicity of the samples was evaluated in vitro and in vivo. Both the samples showed an interesting anti-HP activity, acting on different virulence strains, with the oleoresin reaching a minimum bactericidal concentration of 98?μg/ml against cagA– strain. Moreover, an interesting reduction in IL-6 release was observed, which could be helpful for reducing HP-induced inflammation, thus, preventing complications such as ulcer and irritation of the gastric mucosa. Toxicity was not observed up to 2000?µg/ml. Even if more studies must be conducted, this work supports the use of C. langsdorffii in the management of HP-related gastric disorders.  相似文献   

4.
    
Zooplankton of tropical man-made Lake Kariba was studied from July 1985 to January 1987. Seasonal trends in densities of various zooplankters were investigated from density-time graphs. Periods of peak densities were associated with high nutrient fluxes. There was a rainy season peak and a post turn-over peak. This seasonal pattern was confirmed and more elegantly demonstrated after applying cluster and principal component analysis.  相似文献   

5.
    
Microalgae in the division Haptophyta play key roles in the marine ecosystem and in global biogeochemical processes. Despite their ecological importance, knowledge on seasonal dynamics, community composition and abundance at the species level is limited due to their small cell size and few morphological features visible under the light microscope. Here, we present unique data on haptophyte seasonal diversity and dynamics from two annual cycles, with the taxonomic resolution and sampling depth obtained with high‐throughput sequencing. From outer Oslofjorden, S Norway, nano‐ and picoplanktonic samples were collected monthly for 2 years, and the haptophytes targeted by amplification of RNA/cDNA with Haptophyta‐specific 18S rDNA V4 primers. We obtained 156 operational taxonomic units (OTUs), from c. 400.000 454 pyrosequencing reads, after rigorous bioinformatic filtering and clustering at 99.5%. Most OTUs represented uncultured and/or not yet 18S rDNA‐sequenced species. Haptophyte OTU richness and community composition exhibited high temporal variation and significant yearly periodicity. Richness was highest in September–October (autumn) and lowest in April–May (spring). Some taxa were detected all year, such as Chrysochromulina simplex, Emiliania huxleyi and Phaeocystis cordata, whereas most calcifying coccolithophores only appeared from summer to early winter. We also revealed the seasonal dynamics of OTUs representing putative novel classes (clades HAP‐3–5) or orders (clades D, E, F). Season, light and temperature accounted for 29% of the variation in OTU composition. Residual variation may be related to biotic factors, such as competition and viral infection. This study provides new, in‐depth knowledge on seasonal diversity and dynamics of haptophytes in North Atlantic coastal waters.  相似文献   

6.
    
Two analytical methods were developed in this study for direct and fast chemical investigation of authentic Copaifera oleoresins (COR) and commercial products. Polydimethylsiloxane microfiber coupled to gas chromatography‐mass spectrometry (HS‐SPME‐GC/MS) showed the best results for oleoresin qualitative analysis, setting the following extraction conditions: equilibrium time of 15 min, extraction time of 30 min, extraction temperature at 60 °C and constant stirring of 400 rpm. Sesquiterpenes α‐copaene, β‐elemene, β‐caryophyllene and trans‐α‐bergamotene were found in all investigated samples. Quantitative analysis by gas chromatography coupled with flame ionization detector (GC‐FID) measured the content of the four sesquiterpenes in all samples. Qualitative and quantitative results showed important differences between COR of distinct species and commercial products. Data regarding the volatile composition of C. oblongifolia and C. trapezifolia oleoresins were first presented in this study and two new analytical methods were reported for direct and fast qualitative and quantitative analysis of COR.  相似文献   

7.
    
Increased industrial activities on the Peace and Athabasca River systems have raised concerns about cumulative impacts on fish and water resources downstream, in the Slave River of Alberta and the Northwest Territories, Canada. Because very little information was available on the fish communities in this system, we examined spatial and temporal patterns of diet for nine species (four piscivores and five invertebrate feeders) from three different types of habitat along the lower Slave River system and assessed trophic relationships within the communities. All actively feeding species exhibited seasonal variations in diet within and among the study areas. Dietary overlap was generally low throughout all seasons and locations. In the lower Slave River and its major tributary, the Salt River, substantial dietary overlap between piscivores (particularly walleye, Stizostedion vitreum), and invertebrate feeders occurred in the spring. In the summer no overlap occurred as walleye shifted to a more piscivorous diet, attaining a moderate degree of overlap with northern pike, Esox lucius. Compared with the Slave River, which is a large but homogeneous system upstream of its delta at Great Slave Lake, there was a greater diversity of actively feeding invertebrate feeders in the Salt River. Three of the latter were benthic feeders exhibiting moderate degrees of diet overlap during spring and summer. During the fall, few fish were feeding. Most fishes in the lower Slave River system are generalist, opportunistic feeders, consuming a number of different prey, the importance of which varies spatially and seasonally, as the abundance of these prey varies in the environment.  相似文献   

8.
Leishmaniasis is a neglected tropical disease. According to the World Health Organization, there are approximately 1.5-two million new cases of cutaneous leishmaniasis each year worldwide. Chemotherapy against leishmaniasis is based on pentavalent antimonials, which were developed more than a century ago. The goals of this study were to investigate the antileishmanial activity of diterpene acids in copaiba oil, as well as some possible targets of their action against Leishmania amazonensis. Methyl copalate and agathic, hydroxycopalic, kaurenoic, pinifolic and polyaltic acids isolated from Copaifera officinales oleoresins were utilised. Ultrastructural changes and the specific organelle targets of diterpenes were investigated with electron microscopy and flow cytometry, respectively. All compounds had some level of activity against L. amazonensis. Hydroxycopalic acid and methyl copalate demonstrated the most activity against promastigotes and had 50% inhibitory concentration (IC50) values of 2.5 and 6.0 µg/mL, respectively. However, pinifolic and kaurenoic acid demonstrated the most activity against axenic amastigote and had IC50 values of 3.5 and 4.0 µg/mL, respectively. Agathic, kaurenoic and pinifolic acid caused significant increases in plasma membrane permeability and mitochondrial membrane depolarisation of the protozoan. In conclusion, copaiba oil and its diterpene acids should be explored for the development of new antileishmanial drugs.  相似文献   

9.
10.
合并与不合并:两个相似性聚类分析方法比较   总被引:1,自引:0,他引:1       下载免费PDF全文
以山西省4638种昆虫在7个地理小区的分布、内蒙古7766种昆虫在14个地理小区的分布和中国16804属昆虫在67个生态区域的分布3组数据为样本,用传统的层层合并的相似性聚类分析法(SCA)和新的不需合并的多元相似性聚类分析法(MSCA)进行运算分析,对比结果表明,不合并法都能得到既符合统计学逻辑,又符合地理学、生物学逻辑的结果;合并法在参与小区较少时,还能够得到与不合并法类似的结果,随着参与小区的增多,聚类结构发生变化,以致聚类功能彻底丧失.无论两种聚类结果差异大小,其性质都迥然不同:不合并法的相似性系数是固有的、互相独立的、同时存在的,聚类结果是所有小区之间关系亲疏、距离远近的状态;合并法的每个相似性系数都是合并的依据或结果,前一个系数是后一个系数产生的条件,后一个系数是前一个系数消亡的结果,严格按照顺序,当最后一个系数产生时,前面所有系数和所有小区都已不复存在,聚类结果只是记录不断合并、不断消亡的过程.因此在肯定合并法历史价值的同时,认为申效诚等创建的多元相似性系数公式及多元相似性聚类分析法摈弃合并降阶这一产生偏差和错误的根源,能够得出相对客观的聚类结果,是生物地理学研究领域有效的聚类分析工具,必将推动生物地理学定量研究迈入一个新阶段.  相似文献   

11.
运用气相色谱对在温室栽培的Hymenaea courbaril和Copaifera officinalis及C. pubiflora幼树叶内倍半萜类化合物昼夜和季节性变化进行了分析测定。Hymenaea和Copaifera这二个属植物叶内具有基本相同的一组倍半萜类化合物,对认为具有生态意义的它的主要成分:石竹烯(caryophyllene),α,β-瑟林烯(selinene)和树脂含量进行了分析统计。在三个季节和昼夜的资料中,这二个属植物的石竹烯、α,β-瑟林烯和树脂含量昼夜变化是很小的,而在植株间(遗传型)和不同的季节里它们有明显而有意义的变化。  相似文献   

12.
    
Oils of various species of Copaifera are commonly found in pharmacies and on popular markets and are widely sold for their medicinal properties. However, the chemical variability between and within species and the lack of standardization of these oils have presented barriers to their wider commercialization. With the aim to recognize patterns for the chemical composition of copaiba oils, 22 oil samples of C. multijuga Hayne species were collected, esterified with CH2N2, and characterized by GC‐FID and GC/MS analyses. The chromatographic data were processed using hierarchical cluster analysis (HCA) and principal component analysis (PCA). In total, 35 components were identified in the oils, and the multivariate analyses (MVA) allowed the samples to be divided into three groups, with the sesquiterpenes β‐caryophyllene and caryophyllene oxide as the main components. These sesquiterpenes, which were detected in all the samples analyzed in different concentrations, were the most important constituents in the differentiation of the groups. There was a prevalence of sesquiterpenes in all the oils studied. In conclusion, GC‐FID and GC/MS analyses combined with MVA can be used to determine the chemical composition and to recognize chemical patterns of copaiba oils.  相似文献   

13.
Procedures such as principal component analysis, autocorrelation and cross-correlation, Fourier analysis, Wiener filtering, which have been used so far for the mathematical analysis of VECP mainly serve purpose of quantization and frequency analysis of signals and the evaluation of their intraindividual and interindividual variability. Although some of the above methods are also employed for the differentiation of VECPs, it seems that methods of primarily comparative character are better suited for the classification of different signal forms. This paper reports on results obtained by multivariate analysis of variance.  相似文献   

14.
15.
A principal component and discriminant function analysis of zooplankton from the Sanyati Bay, Lake Kariba, indicated that the distribution of plankton was associated with the riverine in-flow into the lake.  相似文献   

16.
稀有濒危植物翅果油树种群黄酮类化合物多样性研究   总被引:3,自引:1,他引:3  
以稀有濒危植物翅果油树叶中黄酮类化合物为标记,探索翅果油树种群与其生境的相互关系。通过对濒危植物翅果油树的主要分布区,山西省的乡宁、翼城、平陆等三种群及环境的调查,并采集三个种群的24个样品。用水提法、甲醇提法,经聚酰胺薄层层析法分离,并将层析结果作1/0的二元数据化处理,用于聚类分析和PCA排序。结果表明:1)翅果油树叶中黄酮类化合物的种类比较稳定,可以作为研究种群分化的标记物;2)聚类分析表明乡宁、翼城、平陆三个种群间所含的黄酮类化合物已有分化,乡宁种群与翼城种群之间的相异性较小,在截取值为20时,乡宁与翼城种群首先聚为一支,当截取值为25时,平陆种群归并,表明平陆种群与其他种群的相异性较大;3)各种群内个体间的共享率有明显的差异4)PCA分析表明:不同种群内的黄酮类化合物的差异与其地理位置、温度、地形地貌及土壤养分等因子有关。  相似文献   

17.
    
In this article, the in vitro schistosomicidal effects of three Brazilian Copaifera oleoresins (C. duckei, C. langsdorffii, and C. reticulata) are reported. From these botanical sources, the oleoresin of C. duckei (OCd) demonstrated to be the most promising, displaying LC50 values of 75.8, 50.6, and 47.2 μg/ml at 24, 48, and 72 h of incubation, respectively, against adult worms of Schistosoma mansoni, with a selectivity index of 10.26. Therefore, the major compounds from OCd were isolated, and the diterpene, (?)‐polyalthic acid (PA), showed to be active (LC50 values of 41.7, 36.2, and 33.4 μg/ml, respectively, at 24, 48, and 72 h of incubation). Moreover, OCd and PA affected the production and development of eggs, and OCd modified the functionality of the tegument of S. mansoni. Possible synergistic and/or additive effects of this balsam were also verified when a mixture of the two of its main compounds (PA and ent‐labd‐8(17)‐en‐15,18‐dioic acid) in the specific proportion of 3:1 (w/w) was tested. The obtained results indicate that PA should be considered for further investigations against S. mansoni, such as, synergistic (combination with praziquantel (PZQ)) and in vivo studies. It also shows that diterpenes are an important class of natural compounds for the investigation of agents capable of fighting the parasite responsible for human schistosomiasis.  相似文献   

18.
一点红黄酮成分的分析及含量测定   总被引:20,自引:0,他引:20       下载免费PDF全文
对一点红中黄酮类成分进行了定性分析和定量测定,结果表明,在一点红中含有黄酮、黄酮醇、二氢黄酮、二氢黄酮醇等多种黄酮类化合物,并以芦丁为标样,用分光光度法测出总黄酮含量为4.02%。  相似文献   

19.
    
HUGHES  DAVID T.; SAW  JOHN G. 《Biometrika》1972,59(1):224-226
  相似文献   

20.
  总被引:8,自引:0,他引:8  
The advantages and disadvantages of various numerical and graphical techniques for the analysis of inter- and intraspecific feeding relationships of fishes were examined. All methods have been cited in the literature since 1988. The index of preponderance, the resultant index and graphical methods proposed by Costello and Tokeshi were used to illustrate the relative importance of prey species to an individual fish species with no differentiation between size classes. Inter- and intraspecific competition and niche overlap were determined from multivariate analysis [the ordination technique, detrended correspondence analysis, cluster analysis by the Bray-Curtis equation, per cent overlap and two-way indicator species analysis (TWINSPAN)]. The identity of the prey organisms are not lost in the comparisons, and the value of this is determined through comparison with techniques such as Shannon-Wiener which obscure these data. The Shannon-Wiener diversity index was combined with an analysis of 'evenness' to refine the technique further to assess niche breadth, as was the Levins index. The study shows that to give an estimate of competition within the community, it is important to assess the data with respect to seasonal and temporal patterns using multivariate analysis.  相似文献   

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