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1.
Int J Mol Sci ; 16(9): 21109-27, 2015 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-26404257

RESUMO

Aerial parts of Veronica species are used in Romanian traditional medicine for the treatment of various conditions like kidney diseases, cough, and catarrh, and are known for their wound-healing properties. In the present study, the phenolic and sterolic content and the antioxidant and antimicrobial activities of three Veronica species (Plantaginaceae), V. officinalis L., V. teucrium L. and V. orchidea Crantz, were studied. The identification and quantification of several phenolic compounds and phytosterols were performed using LC/MS techniques and the main components were p-coumaric acid, ferulic acid, luteoline, hispidulin and ß-sitosterol. More than that, hispidulin, eupatorin and eupatilin were detected for the first time in the Veronica genus. Nevertheless, representatives of the Veronica genus were never investigated in terms of their phytosterol content. The antioxidant potential investigated by Trolox equivelents antioxidant capacity (TEAC) and EPR spectroscopy revealed that V. officinalis and V. orchidea extracts presented similar antioxidant capacities, whilst the values registered for V. teucrium extract are lower. Regarding the antimicrobial activity of the investigated species, Staphylococcus aureus, Listeria monocytogenes and Listeria ivanovii were the most sensitive strains with MIC values between 3.9 and 15.62 mg/mL. The results obtained by this study may serve to promote better use of representatives from the genus Veronica as antioxidant and antimicrobial agents.


Assuntos
Anti-Infecciosos/farmacologia , Antioxidantes/farmacologia , Compostos Fitoquímicos/análise , Veronica/química , Anti-Infecciosos/química , Antioxidantes/química , Listeria/efeitos dos fármacos , Medicina Tradicional , Fenóis/análise , Fenóis/isolamento & purificação , Fenóis/farmacologia , Compostos Fitoquímicos/isolamento & purificação , Compostos Fitoquímicos/farmacologia , Fitosteróis/análise , Fitosteróis/isolamento & purificação , Fitosteróis/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Veronica/classificação
2.
Syst Biol ; 59(5): 491-503, 2010 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-20693311

RESUMO

We propose a method for delimiting species based on dominant or codominant multilocus data using Gaussian clustering with a noise component for outliers. Case studies show that provisional species delimited using Gaussian clustering based on dominant multilocus data correspond well with provisional species delimited based on other data. However, the performance of Gaussian clustering in delimiting species based on few codominant markers was only moderate. Species represented by few individuals are usually included in the noise component because clusters are difficult to recognize with limited data. As alternative methods, we evaluated two model-based clustering methods originally proposed to infer population structure and assign individuals to populations based on the assumption of Hardy-Weinberg equilibrium within populations, namely STRUCTURE and STRUCTURAMA, as well as the "fields for recombination" approach. The latter resulted in lumping all individuals of each data set with codominant markers together, and whereas STRUCTURE often provides no decision about the number of clusters, STRUCTURAMA usually yields correct or almost correct numbers of clusters. The classification success of STRUCTURAMA analyses based on codominant markers was very good, but its performance with dominant markers was less consistent. Based on the classification success of the different methods for delimiting species with dominant and codominant multilocus markers in the case studies, we recommend using Gaussian clustering for data sets with dominant markers and STRUCTURAMA for data sets with codominant markers.


Assuntos
Especiação Genética , Modelos Genéticos , Software , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Animais , Análise por Conglomerados , Himenópteros/classificação , Himenópteros/genética , Repetições de Microssatélites , Orchidaceae/classificação , Orchidaceae/genética , Veronica/classificação , Veronica/genética
3.
Mol Phylogenet Evol ; 57(2): 771-86, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-20603220

RESUMO

Southeastern Europe is a centre of European biodiversity, but very little is known about factors causing the observed richness. Here, we contribute to fill this gap by reconstructing the spatio-temporal diversification of the cytologically variable and taxonomically intricate complex of Veronica chamaedrys (Plantaginaceae s.l.), growing in open forests, forest edges and grasslands, with flow cytometry, molecular markers (AFLPs, plastid DNA sequences) and morphometry. Our results show that both diploid and tetraploid cytotypes are widespread, but diploids predominate on the southern Balkan Peninsula. Plastid sequences suggest a first split into three main lineages in the mid-Pleistocene and a continuous diversification during the last 0.4 my. Two of the identified plastid lineages coincide with geographically distinct AFLP clusters. Altogether, the genetic data suggest forest refugia on the southern-most Balkan Peninsula (Greece), in Bulgaria, Istria (Croatia and Slovenia) and maybe the southeastern Carpathians (Romania). Morphometric and genetic data show little congruence with current taxonomy.


Assuntos
Classificação , Evolução Molecular , Filogenia , Poliploidia , Veronica/classificação , Veronica/genética , Análise do Polimorfismo de Comprimento de Fragmentos Amplificados , Europa (Continente) , Genoma de Planta/genética , Filogeografia
4.
Mol Phylogenet Evol ; 54(2): 457-71, 2010 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19796701

RESUMO

The cosmopolitan and ecologically diverse genus Veronica with approximately 450 species is the largest genus of the newly circumscribed Plantaginaceae. Previous analyses of Veronica DNA sequences were in stark contrast to traditional systematics. However, analyses did not allow many inferences regarding the relationship between major groups identified, hindering further analysis of diversification and evolutionary trends in the genus. To resolve the backbone relationships of Veronica, we added sequences from additional plastid DNA regions to existing data and analyzed matching data sets for 78 taxa and more than 5000 aligned characters from nuclear ribosomal DNA and plastid DNA regions. The results provide the best resolved and supported estimate of relationships among major groups in the Northern (Veronica s. str.) and Southern Hemisphere (hebes). We present new informal names for the five main species groups within the Southern Hemisphere sect. Hebe. Furthermore, in two instances we provide morphological and karyological characters supporting these relationships. Finally, we present the first evidence from nuclear low-copy CYCLOIDEA2-region to compare results from the plastid genome with the nuclear genome.


Assuntos
Evolução Molecular , Filogenia , Veronica/genética , Teorema de Bayes , Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Genes de Plantas , Genoma de Cloroplastos , Genoma de Planta , Modelos Genéticos , Alinhamento de Sequência , Análise de Sequência de DNA , Veronica/classificação
5.
PLoS One ; 13(6): e0199818, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-29958275

RESUMO

This study exhaustively explores leaf features seeking diagnostic characters to aid the classification (assigning cases to groups, i.e. populations to taxa) in a polyploid plant-species complex. A challenging case study was selected: Veronica subsection Pentasepalae, a taxonomically intricate group. The "divide and conquer" approach was implemented-that is, a difficult primary dataset was split into more manageable subsets. Three techniques were explored: two data-mining tools (artificial neural networks and decision trees) and one unsupervised discriminant analysis. However, only the decision trees and discriminant analysis were finally used to select diagnostic traits. A previously established classification hypothesis based on other data sources was used as a starting point. A guided discriminant analysis (i.e. involving manual character selection) was used to produce a grouping scheme fitting this hypothesis so that it could be taken as a reference. Sequential unsupervised multivariate analysis enabled the recognition of all species and infraspecific taxa; however, a suboptimal classification rate was achieved. Decision trees resulted in better classification rates than unsupervised multivariate analysis, but three complete taxa were misidentified (not present in terminal nodes). The variable selection led to a different grouping scheme in the case of decision trees. The resulting groups displayed low misclassification rates when analyzed using artificial neural networks. The decision trees as well as the discriminant analysis are recommended in the search of diagnostic characters. Due to the high sensitivity that artificial neural networks have to the combination of input/output layers, they are proposed as evaluation tools for morphometric studies. The "divide and conquer" principle is a promising strategy, providing success in the present case study.


Assuntos
Mineração de Dados/métodos , Redes Neurais de Computação , Poliploidia , Veronica/classificação , Veronica/genética
6.
Phytochemistry ; 140: 174-180, 2017 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-28550715

RESUMO

Four simple iridoid glucosides, three known esters of catalpol, seven esters of aucubin, and two phenylethanoids were isolated from Veronica hookeri (syn. Hebe ciliolata; Plantaginaceae). Of these, none of four aromatic (p-methoxybenzoyl, isovanilloyl, veratroyl, caffeoyl) 6-O-esters of aucubin and 6″-O-benzoyl mussaenosidic acid, had been reported from nature before. Similarly, three simple iridoid glucosides, two esters of 6-O-rhamnopyranosylcatapol, and two phenylethanoid glucosides, as well as 1-O-benzoyl-3-α-glucuronosylglycerol, and 1-O-ß-benzoyl rutinoside were isolated from Veronica pinguifolia (syn. Hebe pinguifolia). The compound 3″-O-benzoyl-2″-O-caffeoyl 6-O-rhamnopyranosylcatalpol had not been reported previously. The pattern of the structural features of the iridoid glucosides is overlaid onto the latest molecular phylogenetic framework of Veronica sects. Hebe and Labiatoides, and discussed in the context of evolutionary trends.


Assuntos
Glucosídeos Iridoides/química , Veronica/química , Glucosídeos Iridoides/isolamento & purificação , Estrutura Molecular , Nova Zelândia , Filogenia , Veronica/classificação
7.
Plant Biol (Stuttg) ; 6(6): 673-82, 2004 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-15570471

RESUMO

A molecular phylogenetic tree of the genus Veronica, based on sequences of the ITS region of nuclear ribosomal DNA, provided a framework to test the use of iridoid chemical data in the classification of the genus. The distribution of ten iridoid glucosides, determined in 27 species of Veronica, supported the molecular results. The nine clades of the molecular tree appeared to correlate with a specific pattern of catalpol esters and chromosome base numbers. Some relationships within Veronica, previously suggested on the basis of morphological and karyological characters, were supported by our data. Neither the molecular, nor the chemical features were in favour of the classical circumscription and classification of the genus.


Assuntos
Filogenia , Veronica/genética , DNA Ribossômico/genética , Iridoides/química , Estrutura Molecular , Veronica/classificação
8.
Mol Phylogenet Evol ; 47(1): 319-38, 2008 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-18299210

RESUMO

The alpine genus Chionohebe is one of seven genera in the southern hemisphere Hebe complex. The main aims of this study were to infer the evolutionary relationships and assess phylogeographic patterns among the six species of Chionohebe, determine the origin of the two species with trans-Tasman distributions, and test species delimitations and specimen identifications based on morphology. Analyses of AFLP data recovered five major lineages within Chionohebe, some of which corresponded to species and varieties as currently circumscribed. Although the cushion chionohebes were strongly supported as monophyletic, the sole non-cushion species, C. densifolia, was sister to Parahebe trifida, and thus the AFLP data do not support a monophyletic Chionohebe as usually circumscribed. Strong north/south and west/east phylogeographic patterns were found among and within the main AFLP lineages in New Zealand. Analyses of chloroplast DNA (cpDNA) revealed eight haplotypes in Chionohebe, but these did not correspond to current taxonomy or geography due to widespread interspecific haplotype sharing. Based on both AFLP and cpDNA results, the two trans-Tasman species are shown to have originated in New Zealand and dispersed to Australia independently.


Assuntos
DNA de Cloroplastos/genética , Filogenia , Veronica/classificação , Ásia , Austrália , Geografia , Polimorfismo de Fragmento de Restrição , Veronica/genética
9.
Rev Med Chir Soc Med Nat Iasi ; 111(1): 280-4, 2007.
Artigo em Inglês | MEDLINE | ID: mdl-17595882

RESUMO

UNLABELLED: We have tried to establish some criteria to avoid the substitution of Veronica officinalis (common speedwell) with other species of Veronica genus, especially Veronica chamaedrys (germander speedwell) which is widely spread and has no therapeutic action. MATERIALS AND METHODS: We have studied the differential histological, anatomical and phytochemical characters of these two species. A rapid method for the identification of the two species is the TLC for flavonoids and phenyl-propanic compounds. We have done also a HPLC study, which has permitted the detection of acteoside in Veronica chamaedrys and isoacteoside in Veronica officinalis. In order to confirm the supposed hypocholesterolaemic effect of Veronica officinalis (used in ethno-pharmacy as a hypocholesterolaemic agent) we have done a two step experiment for these two Veronica species. RESULTS: Veronica officinalis in the diet showed no significant effect on the levels of cholesterol and triglycerides in the serum of the cholesterol free diet animals. Veronica officinalis had also a lowering effect on triglycerides and cholesterol level in the serum of high cholesterol diet animals. CONCLUSIONS: A rapid method based on morpho-anatomical and chemical features has been developed in order to avoid substitution of Veronica officinalis with Veronica chamaedrys. For Veronica officinalis we have proved a hypocholesterolaemic effect in high cholesterol diet animals.


Assuntos
Flavonoides/análise , Extratos Vegetais/farmacologia , Plantas Medicinais , Veronica/química , Anti-Infecciosos/farmacologia , HDL-Colesterol/efeitos dos fármacos , Cromatografia Líquida de Alta Pressão , Glucosídeos/farmacologia , Humanos , Fenóis/farmacologia , Veronica/classificação
10.
Ann Bot ; 98(2): 335-50, 2006 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-16775194

RESUMO

BACKGROUND AND AIMS: A new infrageneric rearrangement for Veronica has been proposed based on the most recent evidence from DNA sequence data, morphological evidence, and biogeographical considerations. Looking for morphological synapomorphies for each monophyletic subgenus has been problematic, due to difficulties arising from widespread homoplasy (mainly parallel evolution). In an attempt to overcome these difficulties, previously underexplored morphological characters are starting to be studied in more depth. METHODS: A molecular phylogenetic hypothesis was used based on sequences of ITS (nuclear ribosomal DNA) and plastid trnL-F regions, as a framework to test the use of seed coat ultrastructure (studied under scanning electron microscope) in the systematics of the genus. A sample of 132 taxa representing ten of the 13 subgenera in Veronica, excluding the species of the southern hemisphere Hebe complex and the exclusively North American subgenus Synthyris, was studied. KEY RESULTS AND CONCLUSIONS: The results demonstrate that, in many cases, the ultrastucture of the testa can be employed to assess relationships of taxa within the genus, and the character provides additional support for molecular trees. Further characters relevant for the classification of Veronica, i.e. base chromosome number, iridoid chemical data, life cycle, inflorescence position, have been taken into consideration in a discussion where an attempt is made to highlight the best traits to characterize each subgenus investigated.


Assuntos
Filogenia , Sementes/classificação , Veronica/classificação , Classificação/métodos , DNA de Plantas/análise , DNA Ribossômico/análise , Microscopia Eletrônica de Varredura , Plastídeos/genética , Sementes/ultraestrutura , Análise de Sequência de DNA , Veronica/ultraestrutura
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