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1.
Braz. j. biol ; 83: 1-13, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1468809

RESUMO

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.


Assuntos
Animais , DNA Ribossômico/análise , Fabaceae/crescimento & desenvolvimento , Fungos/patogenicidade , Germinação , Interações entre Hospedeiro e Microrganismos , Plântula/crescimento & desenvolvimento
2.
Braz. j. biol ; 832023.
Artigo em Inglês | LILACS-Express | LILACS, VETINDEX | ID: biblio-1469025

RESUMO

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


Resumo As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.

3.
Braz. j. biol ; 83: e242070, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1278554

RESUMO

Abstract Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


Resumo As interações entre fungos endofíticos (FEs) e suas plantas hospedeiras variam de positivas, neutras a negativas. Os resultados destas interações podem variar dependendo do órgão da planta hospedeira infectada. FEs isolados de folhas de algumas espécies de plantas têm potencial para serem usados como agentes inibidores da germinação de sementes e no controle de plantas invasoras. Os objetivos deste estudo foram identificar os FEs presentes nas folhas de Copaifera oblongifolia e avaliar o papel destes fungos na germinação das sementes e no desenvolvimento das plântulas. Um total de 11 espécies de FEs foi isolado das folhas de C. oblongifolia e identificado através da sequência dos espaçadores internos transcritos do DNA ribossomal nuclear. As espécies de FEs isoladas são generalistas e provavelmente devem ser transmitidas horizontalmente. Os resultados dos testes de germinação mostraram que filtrados destes isolados fúngicos podem afetar diferentemente a germinação das sementes e o desenvolvimento das plântulas de C. oblongifolia. As espécies Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum e Phomopsis sp. afetaram negativamente a germinação das sementes de C. oblongifolia. Dentre estas espécies devemos destacar que N. parvum reduziu a germinação e a sobrevivência das plântulas em 89 e 222%, respectivamente. Além disso, Cochiliobolus intermedius afetou negativamente o desenvolvimento das plântulas. Assim, o uso combinado de N. parvum e C. intermedius, ou de produtos do metabolismo destas espécies de fungos, têm potencial para serem usados no manejo de plantas invasoras.


Assuntos
Germinação , Fabaceae , Ascomicetos , Sementes , Folhas de Planta , Plântula , Fungos , Curvularia
4.
Braz J Biol ; 83: e242070, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-34161452

RESUMO

Interactions between endophytic fungi (EFs) and their host plants range from positive to neutral to negative. The results of such interactions can vary depending on the organ of the infected host plant. EFs isolated from the leaves of some species of plants have potential for use as agents to inhibit seed germination and control invasive plants. The objectives of this study were to identify EFs present in the leaves of Copaifera oblongifolia and to evaluate the role of these fungi in seed germination and seedling development. A total of 11 species of EFs were isolated, which were identified using the internal transcribed spacers (ITS) sequence of the nuclear ribosomal DNA. The isolated species of EFs are generalists and probably are transmitted horizontally. Laboratory tests revealed that filtrates of these fungal isolates differently affect seed germination and seedling development of C. oblongifolia. The species Curvularia intermedia, Neofusicoccum parvum, Pseudofusicoccum stromaticum and Phomopsis sp. negatively affected seed germination, with N. parvum standing out for its negative effects, inhibiting seedling germination and survival in 89 and 222%, respectively. In addition, Cochliobolus intermedius negatively affected seedling development. Thus, the combined use of N. parvum and C. intermedius, or products from the metabolism of these microorganisms, in the control of invasive plants deserves attention from future studies.


Assuntos
Fabaceae , Germinação , Ascomicetos , Curvularia , Fungos , Folhas de Planta , Plântula , Sementes
5.
Genet Mol Res ; 16(3)2017 Sep 27.
Artigo em Inglês | MEDLINE | ID: mdl-28973757

RESUMO

Anacardium humile Saint Hilaire is a tropical shrub native to the Cerrado biome. It is a fruiting species with biological, medicinal, and socioeconomic significance. Thus, knowing how the genetic variability of natural populations is organized allows for the establishment of strategies for conservation and the sustainable use of the species and its biome. Six microsatellite loci previously developed from Anacardium occidentale were used to investigate the spatial genetic structure and genetic diversity of eight natural A. humile populations based on analyses of 242 adult plants. The results obtained indicate that these populations show a high level of genetic diversity (expected heterozygosity = 0.710). The endogamy coefficient was positive and significant for most populations, with a mean of 0.142 (P = 0.001). The genetic differentiation between populations was low (θ = 0.075 and GST = 0.066) but significant (P = 0.0001). The genotypes of five of the eight populations were non-randomly distributed with clusters of related plants for which the coancestry values were positive and significant. These populations exhibited high and significant endogamy indices. The results obtained for A. humile populations show that genetic conservation programs should be implemented to maintain this species.


Assuntos
Anacardiaceae/genética , Genótipo , Polimorfismo Genético , Evolução Molecular , Heterozigoto , Endogamia , Repetições de Microssatélites
6.
Genet Mol Res ; 15(4)2016 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-27808385

RESUMO

Molecular studies of the evolutionary relationships among Leishmania species suggest the presence of high genetic variation within this genus, which has a direct effect on public health in many countries. The coexistence of species in a particular region can result in different leishmaniasis clinical forms and treatment responses. We aimed to standardize the kinetoplast DNA (kDNA) enterobacterial repetitive intergenic consensus (ERIC) sequence polymerase chain reaction (PCR) method for molecular epidemiological identification of Leishmania strains, and estimate existing inter-strain genomic differences and kDNA signatures using this technique. ERIC-PCR of genomic DNA revealed genetic polymorphisms between species, although some strains shared many DNA fragments. Leishmania guyanensis, L. amazonensis, and L. braziliensis clustered together in a dendrogram with similarities ranging from 42.0 to 61.0%, whereas L. chagasi grouped with these three species with a similarity of 28.0%. After amplification of kDNA, 780-bp bands were extracted from an agarose gel and purified for analysis of its genetic signature. kDNA ERIC-PCR electrophoretic patterns consisted of 100- to 600- bp fragments. Using these profiles, L. braziliensis and L. guyanensis grouped with a similarity of 26.0%, and L. amazonensis and L. chagasi clustered based on a similarity of 100%. The electrophoretic profiles and dendrograms showed that, for epidemiological identification by ERIC-PCR, genomic DNA had greater discriminatory power than kDNA did. More strains need to be analyzed to validate the kDNA ERIC-PCR method. The genomes of these strains should be sequenced for better epidemiological identification of Leishmania species.


Assuntos
Leishmania/classificação , Leishmania/genética , Leishmaniose/epidemiologia , Leishmaniose/parasitologia , Reação em Cadeia da Polimerase/métodos , Reação em Cadeia da Polimerase/normas , Sequência de Bases , DNA de Cinetoplasto/genética , Variação Genética , Humanos , Sequências Repetitivas Dispersas
7.
Genet Mol Res ; 15(1)2016 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-27050985

RESUMO

Acrocomia emensis, popularly known as the creeping tucum, belongs to the family Arecaceae, and is an oilseed specie of the Brazilian Savannah. The expansion of agricultural activity has rapidly destroyed its natural habitat, leading to a decrease in its population size. Genetic studies can be used to investigate the genetic variability, and may assist with the charting future conservation strategies. In this study the genetic diversity and structure of 150 individuals sampled in three locations in Minas Gerais were analysed, based on the transferability of six microsatellite markers, previously developed for A. aculeata. The results indicate that the populations studied have low levels of genetic variability (Ho = 0.148) and high, positive and significant inbreeding coefficient, indicating an excess of homozygotes. The average heterozygosity within the population (Hs = 0.700) accounted for 95.03% of the total genetic diversity, indicating that there is greater variability within population than between them, consistent with low genetic differentiation between population (GST = 0.046). Bayesian analysis identified three distinct groups; however, populations shared large numbers of alleles, which can be explained by the reduced distance between populations. These results reveal the need to implement genetic conservation programs for the maintenance of this species and to prioritize population from Bonito and Brasília, which showed the lowest values of genetic diversity.


Assuntos
Arecaceae/genética , Especiação Genética , Repetições de Microssatélites , Polimorfismo Genético , Marcadores Genéticos , Heterozigoto , Endogamia
8.
Rev. bras. plantas med ; 17(4,supl.3): 1125-1133, 2015. tab, graf
Artigo em Português | LILACS | ID: lil-776615

RESUMO

RESUMO Psidium cattleyanum Sabine, conhecida como “araçá”, é espécie nativa do Bioma Cerrado brasileiro comumente utilizado, segundo levantamento etnobotânico, como planta medicinal para tratar várias doenças tais como: patologias hepáticas, gástricas, lesões teciduais incluindo processos dolorosos. O objetivo deste trabalho foi realizar a triagem fitoquímica com propósito exploratório, investigar a atividade analgésica e antimicrobiana do extrato hidroalcoólico da casca do caule de Psidium cattleyanum Sabine (ECPCS) para apoiar o uso dessa espécie como planta medicinal. Para isso, foram obtidos extratos e frações com solventes orgânicos de polaridade crescente (hexano, diclorometano, acetato de etila e isobutanol) avaliando-se o perfil fitoquímico para determinar as principais classes de metabólitos secundários presentes na espécie. Investigou-se a atividade analgésica pelo teste de contorções abdominais em camundongos induzidas pelo ácido acético (0,6%). A Concentração Inibitória Mínina (CIM) e Concentração Bactericida Mínima (CBM) foram avaliadas através da técnica de microdiluição em caldo contra micro-organismos da microbiota oral. A triagem fitoquímica identificou a presença de taninos, saponinas, flavonoides e terpenos e/ou esteroides. O ECPCS exibiu atividade analgésica periférica nas doses de 200 e 400 mg/kg. O EAC (extrato acetato de casca) o EDC (extrato diclorometânico de casca) desempenharam melhor ação inibitória sobre o crescimento bacteriano de Estafilococos oralis com CIM 100 e 150 respectivamente. O ECPCS desempenhou ação inibitória sobre o crescimento bacteriano. Os resultados dos estudos experimentais comprovaram a presença de compostos secundários tais como, taninos e flavonoides, o que, provavelmente, pode ser associado à atividade analgésica e ao efeito inibitório sobre os micro-organismos testados com o ECPCS, o que justifica o uso medicinal planta.


ABSTRACT The Psidium cattleyanum Sabine, known as “araçá”, is a native species from the Brazilian Cerrado biome, commonly used, according to ethnobotanical surveis, as a medicinal plant to treat several sicknesses such as liver and , gastric diseases and tissue lesions with painful treatments. The aim of this study was to perform an exploratory screening, investigating the analgesic and antimicrobial activity of the hydroalcoholic extract of the Psidium cattleyanum Sabine (BEPCS) stem bark, in order to support the use of this species as a medicinal plant. For that, the BEPCS and its parts were obtained from the extraction with organic solvents of increasing polarity (hexane, dichloromethane, ethyl acetate and isobutanol), evaluating its phytochemical profile in order to determine the main types of secondary metabolites present in the species. The analgesic activity, through the twisting test in mice, was investigated and induced by acetic acid (0.6%). The Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) were evaluated using the microdilution technique in liquid against microorganisms of the oral microbiota. The phytochemical screening identified the presence of tannins, saponins, flavonoids and terpenes and/or steroids. The BEPCS exhibited peripheral analgesic activity at the doses of 200 and 400 mg / kg. The AEB (acetate extract bark) and the DEB (dicloromethane extract bark) had better inhibitory effect on bacterial growth of Staphylococcus oraliswith MIC 100 and 150 respectively. The BEPCS demonstrated an inhibitory effect on bacterial growth. The results of experimental studies have indicated the presence of secondary compounds as tannins and flavonoids, which probably can be associated with the analgesic activity and inhibitory effect on the microorganisms tested with BEPCS, fact that justifies the its application.


Assuntos
Ratos , Psidium/química , Analgésicos/classificação , Anti-Infecciosos/classificação , Plantas Medicinais/classificação
9.
Phytother Res ; 21(5): 420-2, 2007 May.
Artigo em Inglês | MEDLINE | ID: mdl-17236178

RESUMO

The activities of the crude ethanol extract from Piper cubeba seeds, (-)-cubebin and its semi-synthetic derivatives were evaluated against oral pathogens. The crude ethanol extract was more active against Streptococcus salivarius (MIC value of 80 microg/mL). (-)-Cubebin displayed MIC values ranging from 0.20 mm for Streptococcus mitis to 0.35 mm for Enterococcus faecalis. The natural product (-)-cubebin and its semi-synthetic derivative (-)-hinokinin displayed bacteriostatic activity at all evaluated concentrations, as well as fungicidal activity against Candida albicans at 0.28 mm. The O-benzyl cubebin derivative showed fungistatic and fungicidal effects against C. albicans at 0.28 mm and 0.35 mm, respectively. Also, the other dibenzylbutyrolactone derivatives [(-)-6,6'-dinitrohinokinin and (-)-O-(N,N-dimethylaminoethyl)-cubebin] displayed bacteriostatic and fungistatic effects at the evaluated concentrations. Moreover, the semi-synthetic derivative (-)-6,6'-dinitrohinokinin was the most active compound against all the evaluated microorganisms. Therefore, it may be suggested that the presence of the carbonyl group at C-9 plus the introduction of polar groups in the aromatic rings improve the antimicrobial activity of dibenzylbutyrolactone compounds.


Assuntos
Anti-Infecciosos/farmacologia , Candida albicans/efeitos dos fármacos , Enterococcus faecalis/efeitos dos fármacos , Lignanas/farmacologia , Piper/química , Streptococcus/efeitos dos fármacos , 4-Butirolactona/análogos & derivados , 4-Butirolactona/química , 4-Butirolactona/farmacologia , Anti-Infecciosos/química , Anti-Infecciosos/isolamento & purificação , Benzodioxóis , Dioxóis/química , Dioxóis/farmacologia , Lignanas/química , Lignanas/isolamento & purificação , Testes de Sensibilidade Microbiana , Extratos Vegetais/química , Extratos Vegetais/farmacologia
10.
Rev. bras. farmacogn ; 13(supl.2): 18-21, 2003. ilus, tab
Artigo em Inglês | LILACS | ID: lil-526480

RESUMO

This work reports the results of the in vitro assay against extracellular forms of Leishmania (viannia) braziliensis of eleven dibenzylbutyrolactone derivatives, either isolated from plants or obtained by synthesis. From these, only two showed relative biological activity against the parasite, the raceme mixtures of methylpluviatolide: IC50 = 496 mM and (-)-6,6'- dinitrocubebin: IC50 = 510,4 μM. Thus, it can be suggested that the metabolic pathway responsible for the biological activity of these compounds against this parasite genera differs from the one related to Trypanosoma cruzi, for which these compounds were quite active. This fact highly also suggests that this class of compounds is more selective against T. cruzi. Nevertheles, other lignans derivatives should be obtained to allow the fully evaluation of this class of lignans against Leishmaniosis.


Este trabalho apresenta os resultados de ensaios in vitro contra formas extracelulares de Leishmania (viannia) braziliensis de onze derivados de dibenzilbutirolactonas isolados de plantas ou obtidos através de síntese. Destes, só dois mostraram atividade biológica relativa contra o parasita, as misturas racêmicas de methilpluviatolide,: IC50 = 496 M e (-) -6,6' - dinitrocubebin: IC50 = 510,4 M. Assim, pode-se sugerir que o caminho metabólico responsável para a atividade biológica destas combinações contra estes gêneros de parasita difere do relacionado a Trypanosoma cruzi para o qual estas combinações foram bastante ativas. Este fato também sugere fortemente que essa classe de combinações é mais seletivo contra T. cruzi. Dessa forma, deveriam ser obtidos outros derivados de lignanas para permitir a completa avaliação desta classe de substâncias contra Leishmaniose.

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