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1.
J Hered ; 109(5): 543-552, 2018 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-29668954

RESUMO

Deforestation-reinforced by illegal logging-is a serious problem in many tropical regions and causes pervasive environmental and economic damage. Existing laws that intend to reduce illegal logging need efficient, fraud resistant control methods. We developed a genetic reference database for Jatoba (Hymenaea courbaril), an important, high value timber species from the Neotropics. The data set can be used for controls on declarations of wood origin. Samples from 308 Hymenaea trees from 12 locations in Brazil, Bolivia, Peru, and French Guiana have been collected and genotyped on 10 nuclear microsatellites (nSSRs), 13 chloroplast SNPs (cpSNP), and 1 chloroplast indel marker. The chloroplast gene markers have been developed using Illumina DNA sequencing. Bayesian cluster analysis divided the individuals based on the nSSRs into 8 genetic groups. Using self-assignment tests, the power of the genetic reference database to judge on declarations on the location has been tested for 3 different assignment methods. We observed a strong genetic differentiation among locations leading to high and reliable self-assignment rates for the locations between 50% to 100% (average of 88%). Although all 3 assignment methods came up with similar mean self-assignment rates, there were differences for some locations linked to the level of genetic diversity, differentiation, and heterozygosity. Our results show that the nuclear and chloroplast gene markers are effective to be used for a genetic certification system and can provide national and international authorities with a robust tool to confirm legality of timber.


Assuntos
Núcleo Celular/genética , DNA de Cloroplastos/genética , DNA de Plantas/genética , Marcadores Genéticos , Hymenaea/genética , Filogeografia , Sequência de Bases , Teorema de Bayes , Análise por Conglomerados , Variação Genética , Heterozigoto , Hymenaea/classificação , Polimorfismo de Nucleotídeo Único , Sequências Repetitivas de Ácido Nucleico , América do Sul
2.
Rev. bras. plantas med ; 18(1,supl.1): 256-263, 2016. tab, graf
Artigo em Português | LILACS | ID: lil-782979

RESUMO

RESUMO O objetivo do presente trabalho foi avaliar a influencia do tamanho e da temperatura na germinação das sementes, assim como, da posição de escarificação do tegumento e a profundidade de semeadura na emergência de plântulas de jutaí. As sementes foram separadas em três grupos: sementes pequenas, médias e grandes. A germinação das sementes foram realizadas nas temperaturas de 5, 10, 15, 20, 25, 30, 35, 40 e 45 °C e com fotoperíodo de 12 horas. As sementes escarificadas foram colocadas para germinar em 0, 2, 4 e 6 cm de profundidade de semeadura. As sementes médias e grandes apresentaram maiores porcentagens e índices de velocidade de germinação. A faixa de temperatura ótima de germinação está entre 25 e 35°C. A escarificação no hilo da semente ou não é adequada para quebra de dormência de sementes de jutaí. Profundidades de semeadura iguais ou superiores a 4 cm são inadequadas para a emergência de plântulas de jutaí.


ABSTRACT The objective of this study was to evaluate the influence of seed size and temperature on seed germination, as well as the scarification position of the tegument and sowing depth on the emergence of jutai seedlings. The seeds were separated into three groups: large, medium and small. The temperatures to which the seeds were subjected for germination were 5, 10, 15, 20, 25, 30, 35, 40, and 45°C under a photoperiod of 12 hours. The scarified seeds were placed to germinate at depths of 0, 2, 4, and 6 cm. Seed germination was affected by seed size (large and medium seeds). The optimum temperature range was found to be between 25 and 35°C. The scarification in the hilum or the tegument was enough to break the dormancy of the jutai seeds. Sowing depths equal to or deeper than 4 cm were found to be inadequate for the emergence of jutai seedlings.


Assuntos
Sementes/classificação , Germinação , Plântula/classificação , Hymenaea/classificação , Temperatura
3.
An Acad Bras Cienc ; 86(3): 1147-50, 2014 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-25029361

RESUMO

In this study we evaluated the action of crude aqueous extracts obtained from rhytidome of Hymenaea stigonocarpa (jatobá-do-cerrado) on Allium cepa meristematic root cells in three concentrations: 0.082, 0.164, 0.328g/mL, at exposure times of 24 and 48 h. The slides were prepared by the crushing technique, and cells analyzed throughout the cell cycle, totaling 5000 for each control group and concentration. It was found that all three concentrations, including the lowest which is considered ideal for use, in all exposure times, had significant antiproliferative action on the cell cycle of this test system. For cells under division, we observed a high number of cells in prophase. Therefore, under the conditions studied H. stigonocarpa indicated to be cytotoxic.


Assuntos
Ciclo Celular/efeitos dos fármacos , Hymenaea/química , Cebolas/citologia , Cebolas/efeitos dos fármacos , Extratos Vegetais/farmacologia , Raízes de Plantas/efeitos dos fármacos , Relação Dose-Resposta a Droga , Hymenaea/classificação , Hymenaea/citologia , Raízes de Plantas/citologia , Fatores de Tempo
4.
Rev. bras. plantas med ; 16(3,supl.1): 693-699, 2014. tab
Artigo em Português | LILACS | ID: lil-727197

RESUMO

Espécies de Jatobá (Hymenaea stigonocarpa Mart. ex Hayne) são tradicionalmente utilizadas para o tratamento de diversas doenças. Estudos quimiotaxonômicos têm relacionado o gênero Hymenaea como fonte potencial de compostos fenólicos, taninos, flavonoides, os quais apresentam atividade antioxidante, sendo assim substâncias potencialmente inibidoras da tirosinase, enzima responsável por defeitos da pigmentação da pele. Existem cerca de 15 espécies no gênero Hymenaea, das quais 13 ocorrem no Brasil. Assim, este trabalho foi realizado para avaliar os fenóis, a atividade antioxidante, a capacidade de quelação dos íons cobre, e a capacidade de inibição da tirosinase do extrato das folhas da espécie H. Stigonocarpa. O material botânico (folhas), foi colhido nas árvores da área de cerrado de preservação ambiental do campus universitário FESURV - Universidade de Rio Verde - GO, seco em estufa de circulação forçada a 42°C por 2 dias, seguindo para a obtenção dos extratos hexânico e etanólico. A determinação do conteúdo fenólico realizada através do reativo Folin Ciocalteau demonstrou ser o extrato bruto etanólico (EBE) o que apresentou a maior concentração dessa classe (235,7 mg equivalente de ácido gálico por grama de EBE). Na avaliação da atividade captadora de radical, empregando o radical livre DPPH, novamente o extrato etanólico demonstrou atividade antioxidante mais elevada (IC50 = 19 ± 0,1 ppm). Para o procedimento de quelação de íons cobre, o extrato bruto etanólico não demonstrou tal capacidade. Quanto a inibição da enzima tirosinase, o extrato bruto etanólico, após 30 e 60 minutos, apresentou inibição de 38 e 48%, respectivamente.


The jatobá species, also known as Brazilian cherry, are traditionally used for the treatment of various diseases. Chemotaxonomic studies have described the Hymenaea genus as a potential source of phenolic compounds, tannins and flavonoids, which have antioxidant activity, thus being potential inhibitors of tyrosinase, which is the enzyme responsible for skin pigmentation defects. There are approximately 15 species in the genus Hymenaea of which 13 are found in Brazil. This study was conducted to evaluate the phenols, the antioxidant activity, the ability to chelate copper ions and the ability to inhibit tyrosinase of the extract of the H. Stigonocarpa leaves. The plant material (leaves) was harvested from trees in the savannah (Brazilian Cerrado) area of environmental preservation of the FESURV campus - University of Rio Verde - state of Goiás, dried in a forced circulation oven at 42° C for 2 days and subjected to extraction with hexane (hexane crude extract) and extraction with absolute ethanol (ethanol crude extract). When determining the phenolic content performed with the Folin-Ciocalteu reagent, we found that the crude ethanol extract (CEE) presented the highest concentration (235.7 mg gallic acid equivalent per gram of CEE). In the evaluation of radical scavenging activity, using the DPPH free radical, the ethanol extract again showed higher antioxidant activity (IC50 = 19 ± 0.1 ppm). For the procedure for chelation of copper ions, the crude ethanol extract tested showed no such ability. For the process of inhibiting the tyrosinase enzyme, the crude ethanol extract tested after 30 and 60 minutes presented inhibition of 38 and 48%, respectively.


Assuntos
Extratos Vegetais/farmacocinética , Monofenol Mono-Oxigenase/antagonistas & inibidores , Folhas de Planta/metabolismo , Hymenaea/classificação , Antioxidantes/análise , Compostos Fenólicos/análise , Radicais Livres/efeitos adversos
5.
J Hered ; 100(2): 206-16, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-18974401

RESUMO

The phylogeography of Hymenaea courbaril var. stilbocarpa from Atlantic Forest and riverine forests of the Cerrado biome in central and southeastern Brazil was investigated. The data were compared with those of its congeneric Hymenaea stigonocarpa, a typical tree from savanna. In the Cerrado, H. courbaril var. stilbocarpa is found in sites contiguous with those of H. stigonocarpa, and they share common life-history attributes. The psbC/trnS3 region of the chloroplast DNA was sequenced in 149 individuals of H. courbaril var. stilbocarpa. High genetic variation was found in this species, with the identification of 18 haplotypes, similarly to what was found in H. stigonocarpa with 23 haplotypes in the same geographic region. Populations of H. courbaril var. stilbocarpa could be structured in 3 phylogeographic groups. Spatial analysis of molecular variation indicated that 46.4% of the genetic variation was due to differences among these groups. Three haplotypes were shared by H. courbaril var. stilbocarpa and H. stigonocarpa, and only 10.5% of the total genetic variation could be attributed to between-species difference. We surmise that during the glacial times, H. courbaril var. stilbocarpa populations must have gone extinct in most parts of the southern of its present-day occurrence area. After climate amelioration, these areas were probably recolonized from northern and eastern. The relatively similar phylogeographic structure of vicariant Hymenaea species suggests that they were subjected to the same impacts during the Quaternary climatic fluctuations. The sharing of haplotypes and the genetic similarity between the 2 Hymenaea species suggest the existence of ancestral polymorphism and/or hybridization.


Assuntos
Hymenaea/classificação , Hymenaea/genética , Filogenia , Brasil , DNA de Plantas/análise , Especiação Genética , Variação Genética , Geografia , Haplótipos , Hymenaea/fisiologia , Análise de Sequência de DNA , Árvores/genética , Árvores/fisiologia
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