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1.
Artigo em Inglês | MEDLINE | ID: mdl-32163004

RESUMO

This study aimed to synthesize Bi2Fe4O9 and apply it to the degradation of tartrazine yellow dye. Bi2Fe4O9 was synthesized using the solid-state reaction and the Pechini method. The materials obtained were characterized using X-ray diffraction (XRD), visible ultraviolet spectroscopy (UV-Vis) and field emission scanning electron microscopy (FEG). The microscopic images revealed a morphological difference between the two materials in which the material obtained by the Pechini method is the most porous and have the largest surface area. The pellet obtained by the Pechini method was seen to have a lower bandgap value when compared with the sample solid state reaction. In the photocatalysis tests, the best performance was also that of the material obtained by the Pechini method, with 99.34% degradation, while the material obtained by solid state reaction showed 85.86% in 120 minutes. The solution degraded with the material obtained by the Pechini method presented 81.66% of mineralization while the solution with the material obtained by solid state reaction showed 60.97% of mineralization. The results confirmed that the material obtained by both syntheses is able to maintain its effectiveness after 10 repetitions of the photocatalytic process, proving to be promising for waste treatment in the industrial field.


Assuntos
Bismuto/química , Corantes/análise , Compostos Férricos/química , Tartrazina/análise , Águas Residuárias/química , Poluentes Químicos da Água/análise , Purificação da Água/métodos , Catálise , Compostos Férricos/síntese química , Microscopia Eletrônica de Varredura , Difração de Raios X
2.
PLoS One ; 14(5): e0216675, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31136587

RESUMO

Taxonomic identifications in some groups of lichen-forming fungi have been challenge largely due to the scarcity of taxonomically relevant features and limitations of morphological and chemical characters traditionally used to distinguish closely related taxa. Delineating species boundaries in closely related species or species complexes often requires a range of multisource data sets and comprehensive analytical methods. Here we aim to examine species boundaries in a group of saxicolous lichen forming fungi, the Aspiciliella intermutans complex (Megasporaceae), widespread mainly in the Mediterranean. We gathered DNA sequences of the nuclear ribosomal internal transcribed spacer (nuITS), the nuclear large subunit (nuLSU), the mitochondrial small subunit (mtSSU) ribosomal DNA, and the DNA replication licensing factor MCM7 from 80 samples mostly from Iran, Caucasia, Greece and eastern Europe. We used a combination of phylogenetic strategies and a variety of empirical, sequence-based species delimitation approaches to infer species boundaries in this group. The latter included: the automatic barcode gap discovery (ABGD), the multispecies coalescent approach *BEAST and Bayesian Phylogenetics and Phylogeography (BPP) program. Different species delimitation scenarios were compared using Bayes factors species delimitation analysis. Furthermore, morphological, chemical, ecological and geographical features of the sampled specimens were examined. Our study uncovered cryptic species diversity in A. intermutans and showed that morphology-based taxonomy may be unreliable, underestimating species diversity in this group of lichens. We identified a total of six species-level lineages in the A. intermutans complex using inferences from multiple empirical operational criteria. We found little corroboration between morphological and ecological features with our proposed candidate species, while secondary metabolite data do not corroborate tree topology. The present study on the A. intermutans species-complex indicates that the genus Aspiciliella, as currently circumscribed, is more diverse in Eurasia than previously expected.


Assuntos
Ascomicetos/classificação , Ascomicetos/genética , Líquens/genética , Núcleo Celular/genética , Código de Barras de DNA Taxonômico/métodos , DNA Fúngico/genética , Líquens/classificação , Região do Mediterrâneo , Fenótipo , Filogenia , Filogeografia , Análise de Sequência de DNA , Especificidade da Espécie
3.
Sci Rep ; 7: 40879, 2017 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-28102303

RESUMO

The Mediterranean region, comprising the Mediterranean Basin and the Macaronesian Islands, represents a center of diversification for many organisms. The genetic structure and connectivity of mainland and island microbial populations has been poorly explored, in particular in the case of symbiotic fungi. Here we investigated genetic diversity and spatial structure of the obligate outcrossing lichen-forming fungus Parmelina carporrhizans in the Mediterranean region. Using eight microsatellite and mating-type markers we showed that fungal populations are highly diverse but lack spatial structure. This is likely due to high connectivity and long distance dispersal of fungal spores. Consistent with low levels of linkage disequilibrium and lack of clonality, we detected both mating-type idiomorphs in all populations. Furthermore we showed that the Macaronesian Islands are the result of colonization from the Mediterranean Basin. The unidirectional gene flow, though, seemed not to be sufficient to counterbalance the effects of drift, resulting in comparatively allelic poor peripheral populations. Our study is the first to shed light on the high connectivity and lack of population structure in natural populations of a strictly sexual lichen fungus. Our data further support the view of the Macaronesian Islands as the end of the colonization road for this symbiotic ascomycete.


Assuntos
Variação Genética , Líquens/microbiologia , Parmeliaceae/genética , Análise Discriminante , Fluxo Gênico , Ilhas , Região do Mediterrâneo , Repetições de Microssatélites/genética , Parmeliaceae/fisiologia , Análise de Componente Principal , Esporos Fúngicos/genética
4.
Environ Sci Pollut Res Int ; 24(7): 6143-6150, 2017 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-27178295

RESUMO

This study presents an attempt to solve two serious environmental problems: the generation of toxic effluents and solid waste disposal. The work proposes recycling cigarette filters with the purpose of degrading reactive dyes, which are used in the textile industry. Filters of smuggled cigarettes were recycled through Fe3+ immobilization on their surface. The material obtained was characterized through Fourier transform infrared spectroscopy (FTIR), atomic absorption spectroscopy (AAS), scanning electron microscopy-energy-dispersive spectroscopy (SEM-EDS), and ultraviolet-visible spectroscopy (UV-vis). The factorial design revealed that the most suitable conditions for the degradation of Reactive Black 5 dye were obtained by using 1 g of material at pH 3.0 in a 100 mg L-1 hydrogen peroxide solution. The material showed excellent performance in the Reactive Black 5 dye degradation process; in 60 min, 99.09 % dye was removed. At pH 7.0, the dye degradation was 72.67 %, indicating that the material prepared can be used at pH values greater than 3.0 without the occurrence of hydrated Fe3+ oxide precipitation. Furthermore, the material showed no loss of catalytic activity after three degradation studies.


Assuntos
Filtração/métodos , Naftalenossulfonatos , Poluentes Químicos da Água , Purificação da Água/métodos , Compostos Férricos/química , Resíduos Industriais , Naftalenossulfonatos/análise , Naftalenossulfonatos/química , Naftalenossulfonatos/isolamento & purificação , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação
5.
PLoS One ; 10(5): e0126981, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25961726

RESUMO

The genetic diversity and population structure of the foliose lichenized fungus Parmelina tiliacea has been analyzed through its geographical range, including samples from Macaronesia (Canary Islands), the Mediterranean, and Eurosiberia. DNA sequences from the nuclear ribosomal internal transcribed spacer, the mitochondrial large subunit ribosomal RNA gene, and the translation elongation factor 1-α were used as molecular markers. The haplotypes of the three markers and the molecular variance analyses of multilocus haplotypes showed the highest diversity in the Canary Islands, while restricted haplotypes occurred at high frequencies in Mediterranean coastal samples. The multilocus haplotypes formed three unevenly distributed clusters (clusters 1-3). In the Canary Islands all the haplotypes were present in a similar proportion, while the coastal Mediterranean sites had almost exclusively haplotypes of cluster 3; cluster 2 predominated in inland Mediterranean sites; and cluster 1 was more abundant in central and northern Europe (Eurosiberian area). The distribution of clusters is partially explained by climatic factors, and its interaction with local spatial structure, but much of the variation remains unexplained. The high frequency of individuals in the Canary Islands with haplotypes shared with other areas suggests that could be a refugium of genetic diversity, and the high frequency of individuals of the Mediterranean coastal sites with restricted haplotypes indicates that gene flow to contiguous areas may be restricted. This is significant for the selection of areas for conservation purposes, as those with most genetic variation may reflect historical factors and biological properties of the species.


Assuntos
Variação Genética , Genética Populacional , Líquens/genética , DNA Intergênico , Ecossistema , Meio Ambiente , Geografia , Haplótipos , Líquens/classificação , Tipagem de Sequências Multilocus , Filogenia , Filogeografia , RNA Ribossômico/genética
6.
PLoS One ; 7(6): e39683, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22745810

RESUMO

In traditional morphology-based concepts many species of lichenized fungi have world-wide distributions. Molecular data have revolutionized the species delimitation in lichens and have demonstrated that we underestimated the diversity of these organisms. The aim of this study is to explore the phylogeography and the evolutionary patterns of the Xanthoparmelia pulla group, a widespread group of one of largest genera of macrolichens. We used a dated phylogeny based on nuITS and nuLSU rDNA sequences and performed an ancestral range reconstruction to understand the processes and explain their current distribution, dating the divergence of the major lineages in the group. An inferred age of radiation of parmelioid lichens and the age of a Parmelia fossil were used as the calibration points for the phylogeny. The results show that many species of the X. pulla group as currently delimited are polyphyletic and five major lineages correlate with their geographical distribution and the biosynthetic pathways of secondary metabolites. South Africa is the area where the X. pulla group radiated during the Miocene times, and currently is the region with the highest genetic, morphological and chemical diversity. From this center of radiation the different lineages migrated by long-distance dispersal to others areas, where secondary radiations developed. The ancestral range reconstruction also detected that a secondary lineage migrated from Australia to South America via long-distance dispersal and subsequent continental radiation.


Assuntos
Ascomicetos/genética , Ascomicetos/classificação , Austrália , Evolução Biológica , Filogenia , África do Sul
7.
PLoS One ; 6(12): e28161, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-22174775

RESUMO

There is a long-standing debate on the extent of vicariance and long-distance dispersal events to explain the current distribution of organisms, especially in those with small diaspores potentially prone to long-distance dispersal. Age estimates of clades play a crucial role in evaluating the impact of these processes. The aim of this study is to understand the evolutionary history of the largest clade of macrolichens, the parmelioid lichens (Parmeliaceae, Lecanoromycetes, Ascomycota) by dating the origin of the group and its major lineages. They have a worldwide distribution with centers of distribution in the Neo- and Paleotropics, and semi-arid subtropical regions of the Southern Hemisphere. Phylogenetic analyses were performed using DNA sequences of nuLSU and mtSSU rDNA, and the protein-coding RPB1 gene. The three DNA regions had different evolutionary rates: RPB1 gave a rate two to four times higher than nuLSU and mtSSU. Divergence times of the major clades were estimated with partitioned BEAST analyses allowing different rates for each DNA region and using a relaxed clock model. Three calibrations points were used to date the tree: an inferred age at the stem of Lecanoromycetes, and two dated fossils: Parmelia in the parmelioid group, and Alectoria. Palaeoclimatic conditions and the palaeogeological area cladogram were compared to the dated phylogeny of parmelioid. The parmelioid group diversified around the K/T boundary, and the major clades diverged during the Eocene and Oligocene. The radiation of the genera occurred through globally changing climatic condition of the early Oligocene, Miocene and early Pliocene. The estimated divergence times are consistent with long-distance dispersal events being the major factor to explain the biogeographical distribution patterns of Southern Hemisphere parmelioids, especially for Africa-Australia disjunctions, because the sequential break-up of Gondwana started much earlier than the origin of these clades. However, our data cannot reject vicariance to explain South America-Australia disjunctions.


Assuntos
Ascomicetos/classificação , Ascomicetos/genética , Variação Genética , Líquens/classificação , Líquens/genética , Paleontologia , Filogenia , Teorema de Bayes , Loci Gênicos/genética , Especificidade da Espécie , Temperatura , Fatores de Tempo
8.
Mol Phylogenet Evol ; 56(1): 125-33, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20399873

RESUMO

The species delimitation in fungi is currently in flux. A growing body of evidence shows that the morphology-based species circumscription underestimates the number of existing species. The large and ever growing number of DNA sequence data of fungi makes it possible to use these to identify potential cases of hidden species, which then need to be studied with extensive taxon samplings. We used Parmeliaceae, one of the largest families of lichenized fungi as a model. Intra- and interspecific distances derived from maximum-likelihood phylogenetic trees inferred from 491 nuclear ITS rDNA sequences were examined for five major clades of parmelioid lichens. The intra- and interspecific distances were well separated in most cases allowing the calculation of a threshold, with exceptions of highly deviating distances in a few cases. These situations are shown to be taxa in which the current delimitation needs revision. Thus the analysis of the distance distributions is shown to be a powerful tool for identifying species complexes.


Assuntos
Ascomicetos/genética , Evolução Molecular , Filogenia , Ascomicetos/classificação , DNA Fúngico/genética , DNA Espaçador Ribossômico/genética , Haplótipos , Funções Verossimilhança , Alinhamento de Sequência , Análise de Sequência de DNA , Especificidade da Espécie
9.
Am J Bot ; 95(1): 98-109, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-21632320

RESUMO

The tribe Genisteae includes genera of great ecological importance in Mediterranean countries because they are dominant elements of many plant communities. Genetic variation and diversification patterns in Stauracanthus (Genisteae) provide information relevant for the study of the processes of diversification in relation to the environmental history of the western Mediterranean. Nineteen populations of S. boivinii and S. genistoides were assessed by 11 chloroplast microsatellite markers, revealing 44 haplotypes. Both species had different haplotypes and contrasting patterns of karyological, morphological, and genetic variation. In the minimum spanning tree of the haplotypes, AMOVA analysis, and nested clade analysis, S. boivinii had high levels of differentiation and restricted gene flow among populations. Allopatric differentiation occurred between the Moroccan and Iberian populations of S. genistoides, although S. genistoides subsp. spectabilis and subsp. vicentinus had high levels of differentiation among populations (F(ST)), whereas S. genistoides subsp. genistoides had a low F(ST). Genetic patterns are discussed in relation to the Messinian salinity crisis (MSC): hard conditions drove plants to refuge habitats along the Atlantic coast and higher altitude areas in the Moroccan mountains (S. genistoides subsp. spectabilis and S. boivinii). After the MSC, S. boivinii underwent polyploidization and expansion, whereas S. genistoides expanded and continued diversifying into S. genistoides subspp. genistoides and vicentinus.

10.
Mycol Res ; 111(Pt 6): 685-92, 2007 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-17601715

RESUMO

Sections of apothecia were used to study the internal morphology of ascospores in the largest monophyletic clade within Parmeliaceae composed of Xanthoparmelia and related genera. The results were compared with fertile representative species of most other parmelioid clades. All the Xanthoparmelia species had spores with a single smooth vacuole, which was peanut-shaped, with different degrees of constriction in the equatorial plane. This differs from the ellipsoid vacuole of other parmelioids. In the Xanthoparmelia clade, sexual reproduction seems much more common than in other parmelioids. Thus, we suggest that the presence of this unique spore morphology might contribute to the evolutionary success of this monophyletic group. Further, the discovery of this useful ascospore character demonstrates that detailed ascospore morphological studies significantly enhance molecular phylogenetic analyses. Ascospore features may be more taxonomically significant in Parmeliaceae than hitherto considered.


Assuntos
Ascomicetos/ultraestrutura , Esporos Fúngicos/ultraestrutura , Ascomicetos/classificação , Ultrassonografia , Vacúolos/diagnóstico por imagem
11.
Am J Bot ; 92(12): 2031-43, 2005 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-21646121

RESUMO

Genetic variation in 27 populations of Ulex species from southern Spain and northern Morocco (Betic-Rif arc) was assessed using 11 chloroplast microsatellite (cpSSR) markers, which revealed 47 different haplotypes. These nonrecombinant, haploid markers allow measurement of genetic variation in closely related species of Ulex where molecular phylogenetic analyses have not provided a clear view of interspecific relationships. Discriminant analysis indicates that the haplotypes are useful to differentiate among species, and analysis of molecular variance (AMOVA) shows high levels of differentiation among populations. The minimum spanning tree (MST), that represents the connections between the haplotypes, suggests that the eastern Rifean U. africanus haplotypes are more genetically related than those from southern Spain. The latter may have lost genetic diversity while colonizing new habitats, eventually differentiating into U. baeticus and U. scaber. Hybridization between these populations, followed by polyploidization, may have originated the tetraploids (U. congestus and U. borgiae) that colonized new habitats associated with acidic rocks. Separate groupings of U. scaber populations may indicate multiple origins from different stocks. Diversification in this group of Ulex species could be related to the opening of the Alboran Sea by Middle Miocene, when the populations from Morocco and Spain became isolated from each other.

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