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1.
PLoS One ; 19(7): e0307289, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39012879

RESUMO

The aim of this study was to evaluate the physicochemical composition and antibacterial activity of Brazilian propolis extracts from different types, concentrations, and extraction solvents and from different regions in Brazil. A total of 21 samples were analyzed, comprising 14 samples from Apis mellifera (12 green, 1 brown, and 1 red) and 7 samples from stingless bees (3 mandaçaia, 2 jataí, 1 hebora, and 1 tubuna). The analyses performed were dry extract, total phenolic content (TPC) and antioxidant activity (DPPH and ABTS). The antibacterial activity was performed by Determination of Minimal Inhibitory Concentration (MIC) and Minimal Bactericidal Concentration (MBC). The results showed that very low levels of phenolic compounds and antioxidant activity decreased the antimicrobial activity of the propolis extracts from tubuna and jataí. However, there was no correlation between the increase in propolis concentration in the extract, and the increase in antimicrobial activity. The highest TPC and antioxidant activity was obtained for green propolis extract made with 70% raw propolis that presented similar antibacterial activity to the samples formulated with 30% or less raw propolis. The aqueous propolis extract showed lower antimicrobial activity compared to the alcoholic extracts, indicating that ethanol is a better solvent for extracting the active compounds from propolis. It was observed that the MIC (0.06 to 0.2 mg/mL) and MBC (0.2 to 0.5 mg/mL) values for Gram-negative bacteria were higher compared to Gram-positive bacteria (MIC 0.001-0.2 mg/mL, and the MBC 0.02-0.5 mg/mL). The propolis extracts that exhibited the highest antimicrobial activities were from stingless bees hebora from the Distrito Federal (DF) and mandaçaia from Santa Catarina, showing comparable efficacy to samples 5, 6, and 7, which were the green propolis from the DF. Hence, these products can be considered an excellent source of bioactive compounds with the potential for utilization in both the pharmaceutical and food industries.


Assuntos
Antibacterianos , Antioxidantes , Testes de Sensibilidade Microbiana , Própole , Animais , Própole/química , Própole/farmacologia , Abelhas , Antibacterianos/farmacologia , Antibacterianos/química , Brasil , Antioxidantes/farmacologia , Antioxidantes/química , Fenóis/farmacologia , Fenóis/química , Fenóis/análise
2.
RSC Adv ; 14(30): 22035-22043, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39006771

RESUMO

This study presents an optimized microwave-assisted method for the green synthesis of silver nanoparticles (AgNPs) using a root extract obtained from Pelargonium sidoides DC. The influence of temperature, reagent concentration, and irradiation time was systematically investigated to enhance synthesis yield. Characterization techniques including XRD, UV-vis, FTIR, XPS, and zetametry were employed to confirm the successful formation of nanoparticles with a metallic silver core (∼17 nm) functionalized with organic molecules derived from the plant extract. The cytotoxicity of AgNPs was assessed using a cell viability assay, while the Minimum Inhibitory Concentration (MIC) of nanoformulation against pathogenic bacteria, including Staphylococcus aureus, Escherichia coli, Pseudomonas aeruginosa, and the carbapenem-resistant Klebsiella pneumoniae (KPC), was determined using the Broth microdilution method. The nanoformulation synthesized with P. sidoides extract exhibited a dose-dependent response, demonstrating superior antimicrobial efficacy compared to the pure plant extract in most cases. The MIC values ranged from 0.85 to 17.1 µg mL-1, with particularly strong performance against the drug resistant KPC strain. The enhanced antimicrobial effect is attributed to the synergistic action of the metallic silver core and phytochemicals from P. sidoides on the surface of nanoparticles, which also contribute to notable colloidal stability of AgNPs at physiological pH levels.

3.
REVISA (Online) ; 9(1): 118-124, jan-mar.2020.
Artigo em Inglês, Português | LILACS | ID: biblio-1051754

RESUMO

Objetivo: Verificar a distribuição do polimorfismo do gene BCL2 (rs1801018), em sua região codante, em pacientes portadores de Acidente Vascular Cerebral Hemorrágico (AVCh)/Aneurisma. Além de associar o presente polimorfismo as manifestações clinicas da doença. Método: O estudo foi conduzido com 158 participantes de pesquisa. Os grupos foram pareados quanto ao sexo e idade. A genotipagem foi conduzida pela técnica PCR-RFLP. Após o cálculo das frequências alélicas e genotípicas de cada grupo, foram utilizados testes estatísticos apropriados para cada tipo de comparação. O nível de significância adotado foi de 5%. Resultados: Os dados indicaram que a frequência dos genótipos apresentou uma diferença estatisticamente significante entre o grupo caso e controle, encontrando-se o genótipo ala43ala na maioria dos participantes de ambos os grupos. Conclusão: A presença do alelo mutante (trh) foi vista como um fator protetor para AVCh/aneurisma. Porém, estudos em outras populações devem ser realizados para se obter uma melhor compreensão sobre a doença AVCh/aneurisma.


Objective: Verify the distribution of the BCL2 gene polymorphism (rs1801018), located in its coding region, in patients with Hemorrhagic Stroke (HS)/Aneurysm (A). Furthermore, to associate this polymorphism with the HS/A clinical manifestations. Method: The study was conducted with 158 research participants and the groups matched by sex and age. Genotyping was done by the PCR-RFLP technique. After calculating the allele and genotype frequencies of each group, appropriate statistical tests were performed for each comparison type with the adopted significance level of 5%. Results: The data indicated that the frequency of the genotypes showed a statistically significant difference between the case and control group, and the ala43ala genotype was found in most participants in both groups. Conclusion: The presence of the mutant allele (trh) was observed as a protective factor for HS/A. However, studies in other populations should be performed to obtain a better understanding of this disease.


Objetivo: Objetivo: Verificar la distribución del polimorfismo del gen BCL2 (rs1801018), en ubicado su región de codificación, en pacientes con accidente cerebrovascular hemorrágico (ACVh)/aneurisma. Asimismo, asociar el presente polimorfismo con las manifestaciones clínicas de la enfermedad. Método: El estudio se realizó con 158 participantes, y los grupos fueron agrupados por sexo y edad. La determinación del genotipo se realizó mediante la técnica PCR-RFLP. Después de calcular las frecuencias de alelos y genotipos de cada grupo, se realizaron pruebas estadísticas apropiadas para cada tipo de comparación con el nivel de significación adoptado de 5%. Resultados: Los datos indicaron que la frecuencia de los genotipos mostró una diferencia estadísticamente significativa entre el grupo caso y el control, con el genotipo ala43ala encontrado en la mayoría de los participantes de ambos grupos. Conclusión: La presencia del alelo mutante (trh) fue visto como un factor protector para el ACVh/aneurisma. Sin embargo, se deben realizar más estudios en otras poblaciones para obtener una mejor comprensión de la enfermedad de ACVh/aneurisma.


Assuntos
Polimorfismo Genético
4.
REVISA (Online) ; 9(1): 24-29, jan-mar.2020.
Artigo em Inglês, Português | LILACS | ID: biblio-1050823

RESUMO

Objetivo: aferir a possível relação do polimorfismo IL1B (-511 C/T) com o prognóstico do AVEH. Método: Para avaliar este questionamento, usou-se uma amostra de 81 indivíduos diagnosticados com AVEH, na qual passaram por análise do polimorfismo IL1B -511 C/T, pela técnica da PCR-RFLP. A análise estatística adotou um nível de significância de 5%. Resultados: a pesquisa mostrou que a presença dos genótipos CC ou CT/TT não resultam uma associação estatística entre o polimorfismo da IL1B com o aparecimento do AVEH (P= 0,174). Conclusão: O estudo demonstrou que a variação de C e T no polimorfismo do gene rs16944 não está associada com os aspectos clínicos selecionados. Também mostrou não haver associação estatística com a manifestação da doença e a variação genotípica.


Objective: To assess the possible relationship between IL1B (-511 C / T) polymorphism and the prognosis of HS. Method: To evaluate this questioning, we used a sample of 81 individuals diagnosed with HS, who underwent analysis of the IL1B-511 C / T polymorphism by the PCR-RFLP technique. Statistical analysis adopted a significance level of 5%. Results: Research has shown that the presence of CC or CT / TT genotypes does not result in a statistical association between IL1B polymorphism and the appearance of HS (P = 0.174). Conclusion: The study demonstrated that C and T variation in rs16944 gene polymorphism is not associated with the selected clinical aspects. It also showed no statistical association with disease manifestation and genotypic variation.


Objetivo: evaluar la posible relación entre el polimorfismo IL1B (-511 C / T) y el pronóstico de AVEH. Método: Para evaluar este cuestionamiento, utilizamos una muestra de 81 individuos diagnosticados con AHV, que se sometieron a análisis del polimorfismo IL1B-511 C / T mediante la técnica PCR-RFLP. El análisis estadístico adoptó un nivel de significación del 5%. Resultados: La investigación ha demostrado que la presencia de genotipos CC o CT / TT no da como resultado una asociación estadística entre el polimorfismo IL1B y la aparición de AVEH (P = 0.174). Conclusión: El estudio demostró que la variación de C y T en el polimorfismo del gen rs16944 no está asociada con los aspectos clínicos seleccionados. Tampoco mostró asociación estadística con la manifestación de la enfermedad y la variación genotípica.


Assuntos
Polimorfismo Genético
5.
RSC Adv ; 10(35): 20676-20681, 2020 May 27.
Artigo em Inglês | MEDLINE | ID: mdl-35517757

RESUMO

We describe here a green method for the preparation of silver nanoparticles (AgNPs), by a microwave-assisted synthesis route using Handroanthus impetiginosus underbark extract, with antibacterial activity. After optimizing the synthesis parameters with a Box-Benhken designed experiment, samples were characterized by powder XRD, TEM, UV-Vis spectroscopy, FTIR and zetametry. Using the overall optimized conditions of synthesis - time of reaction 15 min at 200 °C and plant extract/AgNO3 volume ratio equal to 10% - highly crystalline ∼13.4 nm-sized spherical AgNPs in a well-dispersed colloidal state were obtained. It was also proved that the plant extract compounds act as reductant and capping agents during synthesis to functionalize AgNPs, resulting in a negatively charged surface with high values of zeta potential in a wide range of pH, from acidic to alkaline media. Biological activity tests against Staphylococcus aureus and Escherichia coli and cell viability experiments showed that synthesized AgNPs were not toxic to HaCaT mammalian cells and presented a high efficiency against Gram-positive bacteria (S. aureus). This was associated with the synergistic combination of AgNP silver cores with the capping layer containing natural compounds with antimicrobial properties and considered an alternative to the AgNPs commonly obtained from conventional routes that present antibacterial effectiveness preferentially against Gram-negative strains.

6.
Hig. aliment ; 31(272/273): 97-101, 30/10/2017.
Artigo em Português | LILACS | ID: biblio-876174

RESUMO

No Brasil, a couve minimamente processada é comercializada durante todo o ano e geralmente é considerada segura para o consumo pelos consumidores. Este estudo avaliou a qualidade microbiológica de seis diferentes marcas de couve minimamente processada comercializadas em supermercados de Brasília. As análises realizadas foram: contagem total de bactérias mesófilas e psicrotróficas, determinação de coliformes totais e coliformes termotolerantes e identificação molecular de E. coli, Salmonella spp. e L. monocytogenes por sequenciamento de DNA. Os resultados revelaram que as amostras de couve minimamente processada apresentaram baixa qualidade microbiológica. Coliformes termotolerantes foram encontrados em todas as amostras de couve minimamente processada, com populações superiores a 2 log NMP/g em metade das amostras. Após o sequenciamento de DNA, E. coli O157:H7 foi identificada em 2 das 6 amostras e Salmonella enteritidis foi identificada em 1 das 6 amostras. Listeria monocytogenes foi encontrada em metade das amostras, sendo que a presença desta bactéria é geralmente associada a um período excessivo de armazenamento ou estocagem em temperaturas abusivas. Estes resultados mostraram que a couve minimamente processada exposta ao consumo nos supermercados de Brasília pode ser um veículo para a transmissão de bactérias patogênicas e indicaram a necessidade de melhorar a qualidade na cadeia de produção dos vegetais minimamente processados para garantir a vida útil e a segurança microbiológica desses produtos.(AU)


Assuntos
Humanos , Brassica/microbiologia , Contaminação de Alimentos/análise , Armazenamento de Alimentos/normas , Microbiologia de Alimentos , Temperatura , Amostras de Alimentos , Coliformes , Listeria monocytogenes/isolamento & purificação
7.
Toxicon ; 113: 41-8, 2016 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-26854369

RESUMO

Envenomation by wasp stings is a public health preoccupation, and signals after stings have variable effects depending on the number of attacks and individual sensitivities. Even with the high rate of wasp sting cases, the study of phatophysiological effects of the envenomation is still very incipient. In this context, early and accurate assessment of this prognostic can aid in the reduction of the symptomatology and complete remission of the later symptoms. Then, the present study evaluated the toxicological effects caused by envenomation produced by Synoeca surinama, a wasp easily found in Neotropical regions. In vivo tests comprised the evaluation of LD50 (OECD 423), nociception, edema, myotoxic lesion and hemorrhage induction, in vitro tests were realized to evaluate hemolysis, contractile and coagulation alteration. The envenomation effects observed were dose- and time-dependent; the LD50 observed for S. surinama was 178 µg/kg, approximately 17 times more lethal than that of the honeybee. Moreover, a potent algesic and oedema effect, and weak hemorrhagic signal were observed after injection of the venom wasp. Assays in vitro showed that this venom is able to prolong the clotting time of plasma and to increase creatine kinase levels. Our results demonstrated that this venom induced serious local and systemic effects in mammals and, so, to avoid permanent damage to the patient, health professionals should carefully investigate each accident. Moreover, due to its high occurrence in Neotropical regions, ecological management, particularly in areas with free access of children and elderly, should be performed.


Assuntos
Venenos de Vespas/toxicidade , Vespas/fisiologia , Animais , Relação Dose-Resposta a Droga , Edema/induzido quimicamente , Cobaias , Dose Letal Mediana , Camundongos , Músculo Liso/efeitos dos fármacos , Medição da Dor , Ratos , Venenos de Vespas/administração & dosagem
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