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1.
本文研究紫红獐牙菜7个酮类的分离及抗氧化活性。采用大孔吸附树脂、硅胶、聚酰胺等柱色谱法、重结晶进行分离,NMR、紫外、质谱等波谱学方法进行结构鉴定;以常用抗氧化剂Vc和BHT为阳性对照,通过DPPH·法测定紫红獐牙菜口山酮成分清除自由基的能力,并计算各单体IC50。得出在一定浓度范围内,7个单体化合物的清除能力与浓度呈量效关系;由IC50得出1,3,7,8-四羟基酮、1,5,8-三羟基-3-甲氧基酮、2-D-吡喃葡萄糖基-1,3,6,7-四羟基酮对DPPH自由基清除能力强于Vc;其他单体的抗氧化能力都低于Vc和BHT。说明1,3,7,8-四羟基酮、1,5,8-三羟基-3-甲氧基酮、2-D-吡喃葡萄糖基-1,3,6,7-四羟基酮具有很强抗氧化活性,均可作为有效的天然自由基清除剂,具有很大的开发利用前景。  相似文献   

2.
对显脉獐牙菜(Swertia nervosa)的化学成分研究。采用系统溶剂提取,常规硅胶柱色谱和薄层色谱进行分离纯化,根据化合物的物理、化学性质,UV、IR、MS、1H NMR、13C NMR等波谱鉴定其结构。从显脉獐牙菜中分离得到10个化合物,分别鉴定为1,5,8-三羟基-3-甲氧基酮(1)、1,3,8-三羟基-5-甲氧基酮(2)、5,7,3',4'-四羟基黄酮(3)、3,5,7,3',4'-四羟基黄酮(4)、2-C-β-D-吡喃葡萄糖-1,3,6,7-四羟基酮(5)、獐牙菜苦苷(6)、当药苦酯苷(7)、羟基当药苦酯苷(8)、齐墩果酸(9)、胡萝卜苷(10),化合物3~5、7、8和10为首次从显脉獐牙菜中分离得到。  相似文献   

3.
滇黄芩甙A和B的结构   总被引:3,自引:1,他引:2  
从龙胆科滇黄芩属植物滇黄芩(Veratrilla baillonii Franch)中分离得到两个新的酮二糖甙,经~1H NMR,~(13)C NMR,FAB-MS,MS,2D NMR,UV,IR等物理方法和化学反应,推定为:2,3,4,7-四甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(1)和7-羟基-2,3,4-三甲氧基酮-1-O-β-D-葡萄糖(6←1)-β-D-木糖甙(2),分别命名为:滇黄芩甙A和滇黄芩甙B。  相似文献   

4.
二叶獐牙菜化学成分研究   总被引:1,自引:0,他引:1  
从二叶獐牙菜(Swertia bifolia Batal.)的全草中分离得到了7个化合物,5种口山酮和2种甾醇类化合物。它们的结构经光谱方法分别鉴定为1-羟基-3,5-二甲氧基口山酮(Ⅰ)、1羟基-3,7,8-三甲氧基口山酮(Ⅱ)、1,8二羟基-3,5二甲氧基口山酮(Ⅲ)、1,8二羟基-3,7-二甲氧基口山酮(Ⅳ)、1,7二羟基-3,8-二甲氧基口山酮(Ⅴ)、β-谷甾醇(Ⅵ)、胡萝卜苷(Ⅶ)。  相似文献   

5.
花锚的三个新(口山)酮   总被引:2,自引:0,他引:2  
从花锚(Halenia elliptica D.Don)中又得到三种新的(Ⅵ、Ⅶ、Ⅹ)和两种已知的(Ⅷ、Ⅸ)(口山)酮成分。根据化学反应、光谱数据及其相应衍生物与已知化合物比较,三种新(口山)酮的结构分别确定为1,7-二羟基-2,3,4,5-四甲氧基(口山)酮(Ⅵ),1,5-二羟基-2,3,7-三甲氧基(口山)酮(Ⅶ)及1,2-二羟基-3,4,5-三甲氧基(口山)酮(X)。两种已知(口山)酮分別为1,5-二羟基-2,3-二甲氧基(口山)酮(Ⅷ)和1,7-二羟基-2,3-二甲氧基(口山)酮(Ⅸ)。  相似文献   

6.
用超声法从高原植物椭圆叶花锚的全草中,提取并分离出2种针状结晶化合物;采用元素分析 (EA)、核磁共振波谱 (NMR)、质谱 (MS)、红外光谱 (IR)、紫外光谱 (UV)、熔点测定等分析方法,对其化学结构进行表征;产物分别为1,3-二羟基-4, 5, 8-三甲氧基(口山)酮和1-羟基-2,3,4,8-四甲氧基(口山)酮.  相似文献   

7.
从红厚壳(Calophyllum inophyllum Linn.)枝条乙醇提取物中分离得到11个化合物,通过光谱分析,鉴定其结构为:6-羟基-2,3-二甲氧基 酮 ( 1 ) ,1,3,7-三羟基 酮 ( 2 ) ,1,3,7-三羟基-8-甲氧基 酮( 3 ) ,7-羟基-1,3-二甲氧基 酮( 4 ) ,伪蒲公英甾醇( 5 ) ,1,3,6-三羟基-5,7-二甲氧基 酮( 6 ) ,2-羟基-1-甲氧基 酮 ( 7 ) ,2-羟基-1,8-二甲氧基 酮 ( 8 ) ,1,3,5-三羟基-2-甲氧基 酮 ( 9 ) ,4-羟基 酮 ( 10 ) ,1,3,5-三羟基 酮 ( 11 ) 。化合物 2 ~ 5 为首次从红厚壳属植物中得到,化合物 6 ~ 8 为首次从该植物中得到,化合物 1 为一新的天然产物。细胞毒活性测试结果表明,化合物 9 对人胃癌细胞(SGC-7901)的增殖显示出生长抑制活性, 其IC50值为1.8×10-5 mol/L。  相似文献   

8.
从川西獐牙菜(Swcrtia mussotii Franch)中分离和鉴定了八种咄酮成分,即1,8-二羟基-3,5-二甲氧基(口山)酮Ⅰ,1-羟基-3,5-二甲氧基(口山)酮Ⅱ,1-羟基-3,7,8-三甲氧基咄酮Ⅲ,8-羟基-1,3,5-二甲氧基(口山)酮Ⅳ,1,8-二羟基-3,7-二甲氧基(口山)酮Ⅴ,1,7,8-三羟基-3-甲氧基咄酮Ⅵ,1,7-二羟基-3,4,8-三甲氧基(口山)酮Ⅶ和1,3,8-三羟基-5-甲氧基(口山)酮Ⅷ。其中,1,7-二羟基-3,4,8-三甲氧基(口山)酮为新的天然化合物,命名为藏茵陈(口山)酮(zangyinchenin)。  相似文献   

9.
细萼扁蕾的化学成分研究   总被引:2,自引:0,他引:2  
从细萼扁蕾(Gentianopsis barbata var.stennocaryx H.W.Li ex T.N.Ho)全草中分离得到9种化合物,6种(口山)酮成分,1种黄酮甙,2种三萜酸。经化学和光谱方法,分别鉴定为1-羟基-3,7,8-三甲氧基(口山)酮(Ⅰ),1,7-二羟基-3,8-二甲氧基(口山)酮(Ⅱ),1,7,8-三羟基-3-甲氧基(口山)酮(Ⅲ),1-O-[β-D-吡喃木糖-(1→)-β-D-吡喃葡萄糖]-3,7,8-三甲氧基(口山)酮(Ⅳ),1-O-[β-D-吡喃木糖-(1→6)-β-D-吡喃葡萄糖]-7-羟基-3,8-二甲氧基(口山)酮(Ⅴ),1-O-[β-D-吡喃木塘-(1→6)-β-D-吡喃葡萄糖]-7,8-二羟基-3-甲氧基(口山)酮(Ⅵ),木樨草素-7-O-β-D-葡萄糖甙(Ⅶ),齐墩果酸(Ⅷ)和熊果酸(Ⅸ)。  相似文献   

10.
本文继续报道金不换中另外五种酮成分,其一为新化合物:1,3-二羟基2,7-二甲氧基酮(Ⅰ);其他则为已知化合物:1-羟基2,3,7-三甲氧基酮(Ⅱ),1-羟基2,3,5-三甲氧基酮(Ⅲ),1-羟基2,3,4,5-四甲氧基酮(Ⅳ),1,4-二羟基2,3,7-三甲氧基酮(Ⅴ)。  相似文献   

11.
Benthic invertebrate data from thirty-nine lakes in south-central Ontario were analyzed to determine the effect of choosing particular data standardizations, resemblance measures, and ordination methods on the resultant multivariate summaries. Logarithmic-transformed, 0–1 scaled, and ranked data were used as standardized variables with resemblance measures of Bray-Curtis, Euclidean distance, cosine distance, correlation, covariance and chi-squared distance. Combinations of these measures and standardizations were used in principal components analysis, principal coordinates analysis, non-metric multidimensional scaling, correspondence analysis, and detrended correspondence analysis. Correspondence analysis and principal components analysis using a correlation coefficient provided the most consistent results irrespective of the choice in data standardization. Other approaches using detrended correspondence analysis, principal components analysis, principal coordinates analysis, and non-metric multidimensional scaling provided less consistent results. These latter three methods produced similar results when the abundance data were replaced with ranks or standardized to a 0–1 range. The log-transformed data produced the least consistent results, whereas ranked data were most consistent. Resemblance measures such as the Bray-Curtis and correlation coefficient provided more consistent solutions than measures such as Euclidean distance or the covariance matrix when different data standardizations were used. The cosine distance based on standardized data provided results comparable to the CA and DCA solutions. Overall, CA proved most robust as it demonstrated high consistency irrespective of the data standardizations. The strong influence of data standardization on the other ordination methods emphasizes the importance of this frequently neglected stage of data analysis.  相似文献   

12.
Splenocytes separated by physical means and classified as T cells by immunologic tests and computerized microphotometric analysis are differentiated into subgroups by analysis of the distribution patterns of Feulgen-positive nuclear DNA. In like fashion T cells obtained as purified preparations after separation on a nylon column, and accepted as T cells by micromorphometric analysis were subjected to further computerized morphometric analysis of nuclear DNA to form subgroups of cells. In each case, the number and composition of the detected subgroups were consistent. The classification does not appear to reflect any obvious phases of the cell cycle and is not dependent upon the sex and strain of mice from which the cells were obtained.  相似文献   

13.
陈影  姚方杰  张友民  方明 《菌物学报》2014,33(5):984-996
在木耳栽培种质资源农艺性状调查的基础上,应用数量分类学中的Q型聚类分析法对20个木耳菌株进行分类研究,并对14个农艺性状进行R型聚类分析和主成分分析。结果表明:Q型聚类将20个木耳菌株在欧氏距离6.29处依据子实体朵型性状分为簇生型菌株和菊花型菌株两大类群,菊花型类群在欧式距离4.79处依据生育期性状的原基发生类型划分为分散型和集中型两个亚群;R型聚类表明菌丝体性状(1个)、生育期性状(2个)、子实体性状(8个)等11个农艺性状间相关性较强;主成分分析中,发现子实体背面皱褶、耳片数、原基发生时间、子实体朵型、干耳背面颜色等5个性状是14个农艺性状的第1主成分,贡献率高达62.26%,把第1主成分命名为朵型-生育期构成因子,作为种质评价的指标。  相似文献   

14.
Splenocytes separated by physical means and classified as T cells bay immunologic tests and computerized microphotometric analysis are differentiated into subgroups by analysis of the distribution patterns of Feulgen-positive nuclear DNA. In like fashion T cells obtained as purified preparations after separation on a nylon column, and accepted as T cells by micromorphometric analysis were subjected to further computerized morphometric analysis of nuclear DNA to form subgroups of cells. In each case, the number and composition of the detected subgroups were consistent. The classification does not appear to reflect any obvious phases of the cell cycle and is not dependent upon the sex and strain of mice from which the cells were obtained.  相似文献   

15.
Basicranial features were examined in catarrhine primates and early hominids in order to demonstrate how information about morphological integration can be incorporated into phylogenetic analysis. Hypotheses purporting to explain the functional and structural relationships of basicranial characters were tested using factor analysis. Characters found to be functionally or structurally related to each other were then further examined in order to determine whether there was evidence that they were phylogenetically independent. If phylogenetic independence could not be demonstrated, then the characters were presumed to be integrated and were grouped into a complex. That complex was then treated as if it were a single character for the purposes of cladistic analysis. Factor analysis revealed that five basicranial features may be structurally related to relative brain size in hominoids. Depending on how one defines phylogenetic independence, as few as two, or as many as all of those characters might be morphologically integrated. A cladistic analysis of early hominids based on basicranial features revealed that the use of integrated complexes had a substantial effect on the phylogenetic position of Australopithecus africanus, a species whose relationships are poorly resolved. Moreover, the use of complexes also had an effect on reanalyses of certain published cladistic data sets, implying that those studies might have been biased by patterns of basicranial integration. These results demonstrate that patterns of morphological integration need to be considered carefully in all morphology-based cladistic analyses, regardless of taxon or anatomical focus. However, an important caveat is that the functional and structural hypotheses tested here predicted much higher degrees of integration than were observed. This result warns strongly that hypotheses of integration must be tested before they can be adequately employed in phylogenetic analysis. The uncritical acceptance of an untested hypothesis of integration is likely to be as disruptive to a cladistic analysis as when integration is ignored.  相似文献   

16.
About 20 strains of rhizobia from wild legumes were characterized based on numerical analysis of phenotypic characteristics, nodulating ability, fatty acid methyl esters (FAME) and SDS-PAGE profiles of whole cell proteins. FAME analysis revealed that palmitic (16:0), stearic (18:0) and arachidonic (20:0) were detected in most of wild-legume rhizobia, the latter being uncommon in fatty acid profiles of Rhizobium and Sinorhizobium. Numerical analysis of FAME classified strains of wild-legume rhizobia into 9 clusters and one heterogeneous group. There was both agreement and disagreement with the clustering data based on phenotypic analysis and FAME analysis. Four strains were grouped together in the same cluster based on both methods. However, 4 another strains, which were placed in one cluster of phenotypic analysis, were distributed in several clusters after FAME analysis. SDS-PAGE of whole-cell proteins revealed that the rhizobial strains exhibited protein profiles with peptide bands ranging from 5-19 band per profile and showed molar mass of 110-183 kDa. As in the case of FAME analysis, numerical analysis of protein bands was compared with clustering of phenotypic analysis. Agreement of the two methods was obvious when clustering some strains but conflicted in the classification of some other strains. However, integration of the three methods could be the basis of a polyphasic taxonomy. The twenty strains of wild-legume rhizobia were finally classified as follows: 12 strains related to Rhizobium leguminosarum, 5 strains related to Sinorhizobium meliloti and 3 strains to Rhizobium spp. Rhizobia nodulating wild herb legumes are among indigenous strains nodulating crop legumes in cultivated as well as noncultivated lands.  相似文献   

17.
生态足迹分析方法研究进展   总被引:32,自引:3,他引:29  
作为可持续发展的指标,生态足迹模型得到了广泛的关注和应用.同时,对生态足迹理论和方法的研究也不断深化,出现了将生态足迹分析与物流能流分析、产品生命周期分析、投入产出分析相结合的适用于宏观和微观尺度的各种方法,尤其是最近出现了分配足迹到最终需求类型的“标准化”方法.本文介绍了生态足迹不同方法的产生情况,指出生态足迹分析方法分为过程分析和投入产出分析两套体系,并具体介绍了各种分析方法的特点、适用范围、研究进展和应用情况,建立了较为明晰的生态足迹发展的方法框架.针对当前国内外生态足迹方法的应用现状和趋势,提出重点把握3个方向:统一综合法在国家和区域尺度的研究;探索投入产出法、成分法等方法在国内的应用;加强时间序列研究和多情景预测分析.  相似文献   

18.
用超声法从高原植物椭圆叶花锚的全草中,提取并分离出2种针状结晶化合物;采用元素分析(EA)、核磁共振波谱(NMR)、质谱(MS)、红外光谱(IR)、紫外光谱(UV)、熔点测定等分析方法,对其化学结构进行表征;产物分别为1,3-二羟基-4,5,8-三甲氧基[口山]酮和1-羟基-2,3,4,8-四甲氧基[口山]酮。  相似文献   

19.
Matrix-assisted laser desorption/ionization time-of-flight (MALDI-TOF) mass spectrometry is an established tool for the analysis of proteins, whereas it gained by far less interest in the field of lipid analysis. This method works well with phospholipids as well as organic cell extracts and provides high sensitivity and reproducibility. The aim of the present paper is to extend our previous studies to the analysis of lysophospholipids and phospholipid mixtures. To study the suitability of MALDI-TOF mass spectrometry for the analysis of lysophospholipids, different phospholipids like phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, phosphatidic acid, and phosphatidylinositol as well as their mixtures were digested with phospholipase A(2). Positive and negative ion mass spectra of all phospholipids before and after digestion were recorded. In all these cases, the molecular ions of the expected digestion products could be detected and only a very small extent of further fragmentation was observed. On the other hand, spectra of phospholipid mixtures containing phosphatidylcholine were strongly dominated by phosphatidylcholine and lysophosphatidylcholine signals, which prevented the detection of further phospholipids even if those lipids were present in comparable amounts. This is of paramount interest for the analysis of tissue and cell extracts.  相似文献   

20.
BACKGROUND: Tissue counter analysis is an image analysis tool designed for the detection of structures in complex images at the macroscopic or microscopic scale. As a basic principle, small square or circular measuring masks are randomly placed across the image and image analysis parameters are obtained for each mask. Based on learning sets, statistical classification procedures are generated which facilitate an automated classification of new data sets. OBJECTIVE: To evaluate the influence of the size and shape of the measuring masks as well as the importance of feature selection, statistical procedures and technical preparation of slides on the performance of tissue counter analysis in microscopic images. As main quality measure of the final classification procedure, the percentage of elements that were correctly classified was used. STUDY DESIGN: HE-stained slides of 25 primary cutaneous melanomas were evaluated by tissue counter analysis for the recognition of melanoma elements (section area occupied by tumour cells) in contrast to other tissue elements and background elements. Circular and square measuring masks, various subsets of image analysis features and classification and regression trees compared with linear discriminant analysis as statistical alternatives were used. The percentage of elements that were correctly classified by the various classification procedures was assessed. In order to evaluate the applicability to slides obtained from different laboratories, the best procedure was automatically applied in a test set of another 50 cases of primary melanoma derived from the same laboratory as the learning set and two test sets of 20 cases each derived from two different laboratories, and the measurements of melanoma area in these cases were compared with conventional assessment of vertical tumour thickness. RESULTS: Square measuring masks were slightly superior to circular masks, and larger masks (64 or 128 pixels in diameter) were superior to smaller masks (8 to 32 pixels in diameter). As far as the subsets of image analysis features were concerned, colour features were superior to densitometric and Haralick texture features. Statistical moments of the grey level distribution were of least significance. CART (classification and regression tree) analysis turned out to be superior to linear discriminant analysis. In the best setting, 95% of melanoma tissue elements were correctly recognized. Automated measurement of melanoma area in the independent test sets yielded a correlation of r=0.846 with vertical tumour thickness (p<0.001), similar to the relationship reported for manual measurements. The test sets obtained from different laboratories yielded comparable results. CONCLUSIONS: Large, square measuring masks, colour features and CART analysis provide a useful setting for the automated measurement of melanoma tissue in tissue counter analysis, which can also be used for slides derived from different laboratories.  相似文献   

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