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1.
The chemical composition of the volatile fraction of Ocimum gratissimum concrete (romba) from Madagascar has been determined for the first time by GC/MS and GC-FID. A methyl cinnamate chemotype has been determined for this material, along with a set of compounds typical in essential oils and extracts from plants of the Ocimum genus. Variability was mostly observed on terpenes and terpenoids components. GC-O-MS was also used for a sensory evaluation of this material performed by a master perfumer. The chemical composition of this O. gratissimum extract was then compared with literature data to assess subtle differences between chemotypes of the same species and other species of the same genus within natural variability. A mapping illustrates the occurrence of the cinnamate chemotype in Eastern Africa, India and now Madagascar, while other origins generally present eugenol, thymol, camphor, or linalool chemotypes.  相似文献   

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薄荷属植物挥发性成分及药理作用研究进展   总被引:1,自引:0,他引:1  
薄荷属(Mentha L.)植物广泛分布于世界各地,有着悠久的药食两用史。目前,薄荷属植物挥发性物质主要应用于医药、食品、化妆品、香料、烟草等工业。现代研究表明其挥发性成分主要含有多种单萜类化合物,药理学研究显示其具有抗氧化、抗菌、抗辐射、抗癌、降血压等生物活性。本文主要对该属植物挥发性化学成分及药理作用的研究现状进行综述,以期为进一步开发和利用该属植物提供科学依据。  相似文献   

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Introduction

Hieracium s. str. represents one of the largest and most complex genera of flowering plants. As molecular genetics seems unlikely to disentangle intricate relationships within this reticulate species complex, analysis of flavonoids and phenolic acids, known as good chemosystematic markers, promise to be more reliable. Data about pharmacological activity of Hieracium species are scarce.

Objective

Evaluation of the chemosystematic significance of flavonoids and phenolic acids of methanol extracts of aerial flowering parts of 28 Hieracium species from the Balkans. Additionally, investigation of antioxidant potentials of the extracts.

Methods

Comparative qualitative and quantitative analysis of flavonoids and phenolic acids was performed by LC–MS. Multivariate statistical data analysis included non‐metric multidimensional scaling (nMDS), unweighted pair‐group arithmetic averages (UPGMA) and principal component analysis (PCA). Antioxidant activity was evaluated using three colorimetric tests.

Results

Dominant phenolics in almost all species were luteolin type flavonoids, followed by phenolic acids. Although the investigated Hieracium species share many compounds, the current classification of the genus was supported by nMDS and UPGMA analyses with a good resolution to the group level. Hieracium naegelianum was clearly separated from the other investigated species. Spatial and ecological distances of the samples were likely to influence unexpected differentiation of some groups within H. sect. Pannosa. The vast majority of dominant compounds significantly contributed to differences between taxa. The antioxidant potential of the extracts was satisfactory and in accordance with their phenolics composition.

Conclusions

Comparative LC–MS analysis demonstrated that flavonoids and phenolic acids are good indicators of chemosystematic relationships within Hieracium, particularly between non‐hybrid species and groups from the same location. Copyright © 2017 John Wiley & Sons, Ltd.  相似文献   

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狐粪青霉挥发性物质的抑菌活性及成分分析   总被引:1,自引:0,他引:1  
采用对扣法测定狐粪青霉XY180挥发性物质对植物病原真菌的抑制作用,并采用气相色谱—质谱联用技术(GC-MS)分析狐粪青霉挥发性物质的化学成分。结果表明:狐粪青霉挥发物对植物病原真菌的菌丝生长具有一定的抑制作用,从狐粪青霉菌体的乙醚萃取液中共分离到26个组分,鉴定了其中的13个组分。  相似文献   

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The chemical diversity of Zanthoxylum zanthoxyloides growing wild in Senegal was studied according to volatile compound classes, plant organs and sample locations. The composition of fruit essential oil was investigated using an original targeted approach based on the combination of gas chromatography (GC) and liquid chromatography (LC) both coupled with mass spectrometry (MS). The volatile composition of Zzanthoxyloides fruits exhibited relative high amounts of hydrocarbon monoterpenes (24.3 – 55.8%) and non‐terpenic oxygenated compounds (34.5 – 63.1%). The main components were (E)‐β‐ocimene (12.1 – 39%), octyl acetate (11.6 – 21.8%) and decanol (9.7 – 15.4%). The GC and GC/MS profiling of fruit essential oils showed a chemical variability according to geographical locations of plant material. The LC/MS/MS analysis of fruit oils allowed the detection of seven coumarins in trace content. The chemical composition of fruit essential oils was compared with volatile fractions of leaves and barks (root and trunk) from the same plant station. Hexadecanoic acid, germacrene D and decanal were identified as the major constituents of leaves whereas the barks (root and trunk) were dominated by pellitorine (85.8% and 57%, respectively), an atypic linear compound with amide group. The fruit essential oil exhibited interesting antimicrobial activities against Staphylococcus aureus and Candida albicans, particularly the alcohol fraction of the oil.  相似文献   

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Two new pseudoscorpion species, Neobisium babinzub sp. n., and N. tarae sp. n. (Neobisiidae, Pseudoscorpiones), were collected in soil and leaf-litter on Mt. Stara Planina and Mt. Tara, Serbia, diagnosed and thoroughly illustrated. The main morphological characteristics of the two taxa clearly demonstrate their adaptation to life in soil.  相似文献   

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以开花期的椒样薄荷(Mentha × piperita)、薄荷(M. haplocalyx)和苏格兰留兰香(M. × gentilis)叶片部位提取的精油为研究对象, 通过GC-MS分析, 并采用纸片扩散法研究了3种精油单独使用及与抗生素联合使用时对金黄色葡萄球菌、蜡状芽孢杆菌、大肠杆菌、绿脓杆菌和肺炎克雷伯氏菌的抑制情况。结果表明, (1) 椒样薄荷与薄荷精油中含量最高的成分为薄荷醇、薄荷酮和异薄荷酮, 苏格兰留兰香精油的主要成分为香芹酮和柠檬烯。薄荷和苏格兰留兰香精油符合欧洲药典与ISO标准, 椒样薄荷需要继续改良以提高其精油品质与抑菌功能。(2) 精油单独使用时, Pseudomonas aeruginosa ATCC 15442对椒样薄荷精油和薄荷精油敏感; P. aeruginosa ATCC 27853对薄荷精油和苏格兰留兰香精油敏感。精油与抗生素联合使用时抑菌范围和强度均有所改变: 绿脓杆菌的2个菌株对精油与抗生素的组合最为敏感, 其中, 椒样薄荷精油与头孢他啶的组合对P. aeruginosa ATCC 15442显示出最强的增效作用, 薄荷精油与头孢他啶混合之后对P. aeruginosa ATCC 27853出现拮抗作用。Staphylococcus aureus ATCC 25923对所有精油以及精油与抗生素混合物均有抗性。(3) 椒样薄荷、薄荷和苏格兰留兰香精油的不同成分及其含量差异不仅对精油品质有影响, 而且影响精油对测试菌种的抑制作用, 可考虑将其作为薄荷属植物品质育种的参考指标。  相似文献   

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Dinoflagellate bioluminescence systems operate with or without a luciferin binding protein, representing two distinct modes of light production. However, the distribution, diversity, and evolution of the luciferin binding protein gene within bioluminescent dinoflagellates are not well known. We used PCR to detect and partially sequence this gene from the heterotrophic dinoflagellate Noctiluca scintillans and a group of ecologically important gonyaulacoid species. We report an additional luciferin binding protein gene in N. scintillans which is not attached to luciferase, further to its typical combined bioluminescence gene. This supports the hypothesis that a profound re‐organization of the bioluminescence system has taken place in this organism. We also show that the luciferin binding protein gene is present in the genera Ceratocorys, Gonyaulax, and Protoceratium, and is prevalent in bioluminescent species of Alexandrium. Therefore, this gene is an integral component of the standard molecular bioluminescence machinery in dinoflagellates. Nucleotide sequences showed high within‐strain variation among gene copies, revealing a highly diverse gene family comprising multiple gene types in some organisms. Phylogenetic analyses showed that, in some species, the evolution of the luciferin binding protein gene was different from the organism's general phylogenies, highlighting the complex evolutionary history of dinoflagellate bioluminescence systems.  相似文献   

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Eupatorium (family: Compositae), which comprises nearly 1200 species, is distributed throughout tropical America, Europe, Africa, and Asia. Up to now, the reported constituents from the genus Eupatorium involve flavonoids, terpenoids, pyrrolizidine alkaloids, phenylpropanoids, quinonoids, essential oils, and some others, altogether more than 300 compounds. Studies have shown that Eupatorium and its active principles possess a wide range of pharmacological activities, such as cytotoxic, antifungal, insecticidal, antibacterial, anti‐inflammatory, and antinociceptive activities. Currently, effective monomeric compounds or active parts have been screened for pharmacological activities from Eupatorium in vivo and in vitro. Increasing amount of data supports application and exploitation for new drug development.  相似文献   

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For the first time, the n‐alkane distribution and variability of the epicuticular waxes within 22 Sedum taxa was reported with focus on the chemotaxonomy of native Sedum representatives from the central Balkan Peninsula, compared to their relations with four other species of the Crassulaceae family. By GC/MS and GC‐FID identification and quantification, it was established that n‐alkanes C27, C29, C31, C33, and C35 were the dominant constituents of the examined epicuticular wax samples. Applying multivariate statistical analyses including agglomerative hierarchical clustering (AHC) and principal component analysis (PCA), the relation according to the n‐alkane composition between the examined samples was established. It was shown that the n‐alkane variability of the central Balkan Sedum species was considerable and that n‐alkanes might not be very reliable taxonomic markers for these species.  相似文献   

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The composition of the epicuticular leaf n‐alkanes of eight populations of three Satureja montana subspecies (S. montana L. subsp. pisidica (Wettst.) ?ili? , S. montana L. subsp. montana, and S. montana L. subsp. variegata (Host ) P. W. Ball ), from central and western areas of the Balkan Peninsula was characterized by GC‐FID and GC/MS analyses. In the leaf waxes, 15 n‐alkane homologs with chain‐lengths ranging from C21 to C35 were identified. The main n‐alkane in almost all samples was n‐nonacosane (C29), but differences in the contents of three other dominant n‐alkanes allowed separating the coastal from the continental populations. The diversity and variability of the epicuticular‐leaf‐n‐alkane patterns and their relation to different geographic and bioclimatic parameters were analyzed by several statistical methods (principal component, discriminant, and cluster analyses as well as the Mantel test). All tests showed a high correlation between the leaf n‐alkane pattern and the geographical distribution of the investigated populations, confirming the differentiation between S. montana subsp. pisidica and the other two subspecies. The S. montana subsp. variegata and S. montana subsp. montana populations are geographically closer and their differentiation according to the leaf‐n‐alkane patterns was not clear, even though there was some indication of discrimination between them. Moreover, most of the bioclimatic parameters related to temperature were highly correlated with the differentiation of the coastal and the continental populations.  相似文献   

17.
The chemical composition of epicuticular waxes of nine populations from three Pinus nigra J. F. Arnold subspecies (namely subsp. nigra, subsp. banatica (Borbás ) Novák , and subsp. pallasiana (Lamb .) Holmboe ) from Southern Carpathians and central Balkan Peninsula were analyzed using GC/MS and GC/FID chromatography, and multivariate statistical techniques with respect to biogeography and taxonomy. In the needle waxes, four primary alcohols and 14 n‐alkanes ranging from C21 to C33 were identified, and the most abundant compounds were the four odd‐numbered n‐alkanes C27, C25, C23, and C29. Multivariate statistical analyses (CDA and CA) have shown existence of three P. nigra groups and suggested clinal differentiation as a mechanism of genetic variation across a geographic area: the first group consisted of the southernmost populations of subsp. pallasiana from Macedonia, the second consisted of the northernmost subsp. banatica populations from Romania, while all populations in Serbia described as three different subspecies (nigra, banatica, and pallasiana) formed the third group together with subsp. nigra population from Bosnia and Herzegovina. According to simple linear regression, geographic latitude and four bioclimatic parameters were moderately correlated with the contents of epicuticular wax compounds that are important in population discrimination, while stepwise multiple regression showed that latitude participated in most of the regression models for predicting the composition of the epicuticular waxes. These results agree with CDA and CA analysis, and confirmed the possibility of recognition of fine geographic differentiation of the analyzed P. nigra populations.  相似文献   

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This article addresses agricultural metabolism and transitions for energy, nitrogen, farm production, self‐sufficiency, and surplus from historical data since the nineteenth century. It builds on an empirical data set on agricultural production and production means in France covering 130 consecutive years (1882–2013). Agricultural transitions have increased the net production and surplus of farms by a factor of 4 and have zeroed self‐sufficiency. The energy consumption remained quasi‐stable since 1882, but the energy and nitrogen structure of agriculture fully changed. With an EROI (energy return to energy invested) of 2 until 1950, preindustrial agriculture consumed as much energy to function as it provided in exportable surplus to sustain the nonagricultural population. The EROI doubled to 4 over the last 60 years, driven, on the one hand, by efficiency improvements in traction through the replacement of draft animals by motors and, on the other hand, by the joint increase in crop yields and efficiency in nitrogen use. Agricultural energy and nitrogen transitions shifted France from a self‐sufficiency agri‐food‐energy regime to a fossil‐dependent food export regime. Knowledge of resource conversion mechanisms over the long duration highlights the effects of changing agricultural metabolism on the system's feeding capacity. Farm self‐sufficiency is an asset against fossil fuel constraints, price volatility, and greenhouse gas emissions, but it equates to lower farm surplus in support of urbanization.  相似文献   

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Asteriscus graveolens is an endemic medicinal plant mainly distributed in south‐western Algeria and south‐eastern Morocco. The essential oils of leaves, stems, and flowers of A. graveolens had been studied by GC, GC/MS, and 13C‐NMR. The spectral data of two nerolidol derivatives, 6‐oxo‐ and 6‐hydroxycyclonerolidol, were reassigned by 1D‐ and 2D‐NMR spectroscopy. These compounds can be considered as chemical markers of this genus. The structure of a monoterpenic diester with a chrysanthenane skeleton, i.e., cis‐8‐acetoxychrysanthenyl acetate, was determined for the first time on the basis of GC/MS, and 1D‐ and 2D‐NMR. The stem and leaf oils were characterized by high content of oxygenated sesquiterpenes with 6‐oxo‐ and 6‐hydroxycyclonerolidol as major components, and the flower essential oils were dominated by the new monoterpenic compound cis‐8‐acetoxychrysanthenyl acetate.  相似文献   

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To clarify the structure of microbial food webs in groundwater, knowledge about the protist diversity and feeding strategies is essential. We applied cultivation‐dependent approaches and molecular methods for further understanding of protist diversity in groundwater. Groundwater was sampled from a karstified aquifer located in the Thuringian Basin (Thuringia, Germany). Cultivable protist abundance estimated up to 8,000 cells/L. Eleven flagellates, 10 naked amoebae, and one ciliate morpho‐species were detected in groundwater enrichment cultures. Most of the flagellates morpho‐species, typically < 10 μm, were sessile or free swimming suspension feeders, e.g., Spumella spp., Monosiga spp., and mobile, surface‐associated forms that grasp biofilms, e.g., Bodo spp. Naked amoebae, typically < 35 μm, that grasp biofilms were represented by, e.g., Vahlkampfia spp., Vannella spp., and Hartmanella spp. The largest fraction of the 18S rRNA gene sequences was affiliated with Spumella‐like Stramenopiles. Besides, also sequences affiliated with fungi and metazoan grazers were detected in clone libraries of the groundwater. We hypothesize that small sized protist species take refuge in the structured surface of the fractures and fissures of the karstified aquifer and mainly feed on biofilm‐associated or suspended bacteria.  相似文献   

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