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1.
An Acad Bras Cienc ; 96(1): e20200031, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38359287

RESUMO

The potential of H. virginiana L. was evaluated against Candida spp. (C. albicans, C. dubliniensis, C. glabrata, C. guilliermondii, C. krusei, and C. tropicalis) and bacteria (Acinetobacter baumannii, Escherichia coli, Enterococcus faecalis, Klebsiella pneumoniae, Staphylococcus aureus, and Streptococcus mutans). Effect on murine macrophages (RAW 264.7) was also evaluated with respect to cytotoxicity and production of cytokines (IL-1ß and TNF-α) and nitric oxide (NO). The most effective concentrations of the extract were determined by microdilution broth. These concentrations were analyzed on biofilms, after 5 min or 24 h exposure. Cytotoxicity was performed by MTT assay and quantification of cytokines and NO by ELISA and Griess reagent, respectively. The extract acted against the planktonic forms and provided significant reductions of all the microbial biofilms; besides, showed no cytotoxic effect, except at 100 mg/mL, after 24 h exposure. There was cytokine production; however, a modulatory effect was observed in groups exposed to lipopolysaccharide (LPS) from E. coli. NO production was similar or higher than the control group. Thus, H. virginiana L. extract showed antimicrobial and antibiofilm effects; absence of cytotoxicity for RAW 264.7; anti-inflammatory action; and potential to fight infections through the NO production.


Assuntos
Anti-Infecciosos , Candida , Óxido Nítrico , Animais , Camundongos , Hamamelis , Candida albicans , Escherichia coli , Extratos Vegetais/farmacologia , Anti-Infecciosos/farmacologia , Macrófagos , Anti-Inflamatórios/farmacologia , Citocinas , Biofilmes
2.
An Acad Bras Cienc ; 93(2): e20190366, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33950151

RESUMO

Candida spp. are naturally opportunistic and can promote infections. These yeasts can form biofilm, after penetration and adhesion to the biotic or abiotic surfaces. Preexisting diseases, treatments with drugs and radiation therapy, medical procedures, and parafunctional habits favor the installation of a fungal infection. Increased resistance to the available antifungals has become a concern. Therefore, alternative methods to control them have been evaluated, including the use of plant substances. In this study, the antibiofilm effect of R. officinalis L. extract was analyzed on C. albicans, C. dubliniensis, C. glabrata, C. krusei, and C. tropicalis. A phytochemical analysis of the extract was performed. Biofilms were formed for 48 h and exposed to the different concentrations of the extract (50, 100, and 200 mg/mL) for 5 min or 24 h. The effect of the plant extract was compared to the antifungal nystatin. Rosmarinus officinalis L. extract was constituted of phenols and flavonoids, highlighting the presence of chlorogenic acid derivatives in its composition. Biofilm reductions were observed after exposure to the plant extract for both periods. The plant extract provided a reduction similar to the antifungal. Thus, R. officinalis L. extract showed antibiofilm effect on Candida spp. comparable to the nystatin.


Assuntos
Candida , Rosmarinus , Antifúngicos/farmacologia , Biofilmes , Candida albicans , Testes de Sensibilidade Microbiana , Nistatina/farmacologia , Extratos Vegetais/farmacologia
3.
Future Microbiol ; 15: 1237-1248, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-33026878

RESUMO

Aim: Plant products have been evaluated to control opportunistic micro-organisms, as well as fortify immune system cells. Thus, Curcuma longa L. (turmeric) extract was evaluated in interactions of murine macrophages (RAW 264.7) with Staphylococcus aureus, Pseudomonas aeruginosa and Candida albicans, in order to establish cooperation with defense cells. Materials & methods: Effects of minimal inhibitory concentrations (MIC) of the plant extract were analyzed on phagocytosis, cell viability of RAW 264.7 and production of inflammation-related molecules (IL-1ß, TNF-α, IL-10 and NO). Results: The plant extract was cytocompatible and promoted significant reductions of micro-organisms, and synthesis of inflammation-related molecules, during interactions. Conclusion:C. longa L. extract showed significant antimicrobial response and cooperation with macrophages, by fighting bacteria and yeasts during host-microbe interactions.


Assuntos
Anti-Infecciosos/farmacologia , Macrófagos/efeitos dos fármacos , Macrófagos/microbiologia , Extratos Vegetais/farmacologia , Animais , Anti-Infecciosos/química , Candida albicans/efeitos dos fármacos , Candida albicans/fisiologia , Sobrevivência Celular/efeitos dos fármacos , Curcuma/química , Citocinas/metabolismo , Interações Hospedeiro-Patógeno/efeitos dos fármacos , Macrófagos/metabolismo , Camundongos , Testes de Sensibilidade Microbiana , Óxido Nítrico/metabolismo , Fagocitose/efeitos dos fármacos , Extratos Vegetais/química , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/fisiologia , Células RAW 264.7 , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/fisiologia
4.
Z Naturforsch C J Biosci ; 67(5-6): 249-56, 2012.
Artigo em Inglês | MEDLINE | ID: mdl-22888529

RESUMO

Propolis, a natural bee product widely used for its antimicrobial activity, was tested against isolates of Enterococcus from humans, pig-tailed macaques, isolates of refractory endodontic treatment cases, and isolates from Lactobacillus-containing food supplements. Typification of the propolis was performed by high-performance liquid chromatography (HPLC) by which prenylated compounds, cinnamic acid derivatives, and flavonoids were detected as the main constituents. Minimum inhibitory concentrations (MIC) were determined using the agar dilution method. All human and animal Enterococcus isolates demonstrated MIC values of 1600 microg/mL. Enterococcal species of human and animal origin were inhibited by propolis. Particularly, human isolates of E. faecium and E. faecalis of refractory endodontic treatment cases were susceptible to propolis of Brazilian origin.


Assuntos
Enterococcus/efeitos dos fármacos , Própole/farmacologia , Cromatografia Líquida de Alta Pressão , Testes de Sensibilidade Microbiana , Espectrofotometria Ultravioleta
5.
Mem Inst Oswaldo Cruz ; 105(7): 908-13, 2010 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-21120362

RESUMO

Adjuvants play an important role in vaccine formulations by increasing their immunogenicity. In this study, the phenolic compound-rich J fraction (JFR) of a Brazilian green propolis methanolic extract stimulated cellular and humoral immune responses when co-administered with an inactivated vaccine against swine herpesvirus type 1 (SuHV-1). When compared to control vaccines that used aluminium hydroxide as an adjuvant, the use of 10 mg/dose of JFR significantly increased (p < 0.05) neutralizing antibody titres against SuHV-1, as well as the percentage of protected animals following SuHV-1 challenge (p < 0.01). Furthermore, addition of phenolic compounds potentiated the performance of the control vaccine, leading to increased cellular and humoral immune responses and enhanced protection of animals after SuHV-1 challenge (p < 0.05). Prenylated compounds such as Artepillin C that are found in large quantities in JFR are likely to be the substances that are responsible for the adjuvant activity.


Assuntos
Anticorpos Antivirais/imunologia , Herpesvirus Suídeo 1/imunologia , Vacinas contra Herpesvirus/imunologia , Própole/química , Pseudorraiva/prevenção & controle , Adjuvantes Imunológicos , Animais , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Camundongos , Camundongos Endogâmicos BALB C , Pseudorraiva/imunologia , Suínos , Vacinas de Produtos Inativados/imunologia
6.
Mem. Inst. Oswaldo Cruz ; 105(7): 908-913, Nov. 2010. ilus, graf
Artigo em Inglês | LILACS | ID: lil-566182

RESUMO

Adjuvants play an important role in vaccine formulations by increasing their immunogenicity. In this study, the phenolic compound-rich J fraction (JFR) of a Brazilian green propolis methanolic extract stimulated cellular and humoral immune responses when co-administered with an inactivated vaccine against swine herpesvirus type 1 (SuHV-1). When compared to control vaccines that used aluminium hydroxide as an adjuvant, the use of 10 mg/dose of JFR significantly increased (p < 0.05) neutralizing antibody titres against SuHV-1, as well as the percentage of protected animals following SuHV-1 challenge (p < 0.01). Furthermore, addition of phenolic compounds potentiated the performance of the control vaccine, leading to increased cellular and humoral immune responses and enhanced protection of animals after SuHV-1 challenge (p < 0.05). Prenylated compounds such as Artepillin C that are found in large quantities in JFR are likely to be the substances that are responsible for the adjuvant activity.


Assuntos
Animais , Camundongos , Anticorpos Antivirais/imunologia , Herpesvirus Suídeo 1/imunologia , Vacinas contra Herpesvirus/imunologia , Própole , Pseudorraiva , Adjuvantes Imunológicos , Imunidade Celular/imunologia , Imunidade Humoral/imunologia , Camundongos Endogâmicos BALB C , Pseudorraiva/imunologia , Suínos , Vacinas de Produtos Inativados/imunologia
7.
Rev. bras. farmacogn ; 20(3): 368-375, jun.-jul. 2010. ilus
Artigo em Inglês | LILACS | ID: lil-555917

RESUMO

Microemulsion systems (MES) offer advantages as drug delivery systems, among them favour drug absorption, being in most case more efficient than other methods in delivering of drug. In this work a new MES was obtained in order to be applied as a pressurized aerosol formulation containing bee propolis ethanolic extract (PEE). For that, pseudoternary phase diagrams were used to characterize the microemulsions boundaries and also to define the Winsor IV microemulsion region of the PEE-MES system containing Tween 80 as surfactant and the cosurfactant ethyl alcohol in small percentage. The obtained results indicated that the best MES was composed by Tween 80 and ethyl alcohol with C/S (cosurfactant/surfactant) ratio equal to 1.0, since it provided a large boundaries in the obtained O/W microemulsion region. This PEE-MES formulation, in which bee propolis consisting as oil phase, is herein designed for topical uses (PEE-MES spraying) in order to treat mouth and throat inflammatory infections. Considering the very large uses of bee propolis in conventional vehicles, MES type of delivery system has to be compatible with achieving the highest drug aim loadings, determined substantially by the specific MES application (drug solubilization in water systems) improving in this case, propolis farmacological aplications. Additionally, PEE-MES antibacterial effect was evidenced and the microemulsion system PEE-MES was also used as newest chemical approach for extraction of bee propolis material from resinous hive.


Sistemas microemulsionados (MES) oferecem inúmeras vantagens como liberadores de fármacos já que favorecem a absorção do princípio ativo e são, em muitos casos, mais eficientes do que outros métodos de liberação de substâncias bioativas. Neste trabalho, um MES foi obtido visando uma formulação para uso tópico, contendo extrato etanólico de própolis (PEE). Neste estudo, Diagramas de fase pseudoternários foram utilizados para caracterização das regiões de microemulsão, bem como para definição da região de Winsor IV do sistema PEE-MES (Tween 80 como tensoativo e álcool etílico como co-tensoativo, em baixo percentual). Os resultados obtidos indicaram que o melhor sistema microemulsionado contém C/S (cotensoativo/tensoativo) na razão 1,0, fornecendo uma microemulsão do tipo O/A com ampla região de Winsor IV. A formulação PEE-MES poderá vir a ser utilizada comercialmente para uso tópico no combate a inflamações de boca e garganta. Considerando o amplo uso de própolis em formulações convencionais, onde sua solubilidade representa um dos maiores problemas, o sistema PEE-MES disponibiliza este produto natural para aplicações farmacológicas, com boa solubilidade em um sistema microemulsionado do tipo O/A. Adicionalmente, o efeito bactericida do sistema PEE-MES foi comprovado e uma nova metodologia de extração de própolis é apresentada.

8.
Molecules ; 12(7): 1352-66, 2007 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-17909491

RESUMO

The antioxidant activity of flavonoids is believed to increase when they are coordinated with transition metal ions. However, the literature on this subject is contradictory and the outcome seems to largely depend on the experimental conditions. In order to understand the contribution of the metal coordination and the type of interaction between a flavonoid and the metal ion, in this study a new metal complex of Cu (II) with naringin was synthesized and characterized by FT-IR, UV-VIS, mass spectrometry (ESI-MS/MS), elemental analysis and 1H-NMR. The results of these analyses indicate that the complex has a Cu (II) ion coordinated via positions 4 and 5 of the flavonoid. The antioxidant, anti-inflammatory and antimicrobial activities of this complex were studied and compared with the activity of free naringin. The Naringin-Cu (II) complex 1 showed higher antioxidant, anti-inflammatory and tumor cell cytotoxicity activities than free naringin without reducing cell viability.


Assuntos
Antibacterianos/farmacologia , Anti-Inflamatórios/farmacologia , Antioxidantes/farmacologia , Cobre/química , Flavanonas/síntese química , Flavanonas/farmacologia , Animais , Compostos de Bifenilo/química , Ciclo Celular/efeitos dos fármacos , Morte Celular/efeitos dos fármacos , Ensaios de Seleção de Medicamentos Antitumorais , Flavanonas/administração & dosagem , Flavanonas/química , Sequestradores de Radicais Livres/química , Humanos , Hidrazinas/química , Concentração de Íons de Hidrogênio , Células K562 , Espectroscopia de Ressonância Magnética , Masculino , Camundongos , Testes de Sensibilidade Microbiana , Picratos , Espectrometria de Massas por Ionização por Electrospray , Espectrofotometria Ultravioleta
9.
Talanta ; 71(5): 1926-31, 2007 Mar 30.
Artigo em Inglês | MEDLINE | ID: mdl-19071543

RESUMO

Attenuated total reflectance-Fourier transform infrared spectrometry, in conjunction with multivariate calibration, was used for determination of reducing sugars, humidity and acidity in honey bee samples. Multivariate calibration models were built using partial least squares (PLS) and were refined through variable selection per interval (iPLS) and genetic algorithms. The calibration models show satisfactory results for all parameters with average relative errors of 6% for acidity, 1% for reducing sugars and 2% for humidity. For the acidity and reducing sugars parameters, variable selection was irrelevant, but for humidity it was essential. For the humidity parameter, it was necessary to use two variable selection techniques (by intervals and genetic algorithm) concomitantly in order to obtain a satisfactory calibration model.

10.
Analyst ; 129(8): 739-44, 2004 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-15284918

RESUMO

Crude ethanolic extracts of propolis, a natural resin, have been directly analysed using electrospray ionization mass (ESI-MS) and tandem mass spectrometry (ESI-MS/MS) in the negative ion mode. European, North American and African samples have been analyzed, but emphasis has been given to Brazilian propolis which displays diverse and region-dependent chemical composition. ESI-MS provides characteristic fingerprint mass spectra, with propolis samples being divided into well-defined groups directly related to their geographical origins. Chemometric multivariate analysis statistically demonstrates the reliability of the ESI-MS fingerprinting method for propolis. On-line ESI-MS/MS tandem mass spectrometry of characteristic [M - H](-) ion markers provides an additional dimension of fingerprinting selectivity, while structurally characterizing the ESI-MS marker components of propolis. By comparison with standards, eight such markers have been identified: para-coumaric acid, 3-methoxy-4-hydroxycinnamaldehyde, 2,2-dimethyl-6-carboxyethenyl-2H-1-benzopyran, 3-prenyl-4-hydroxycinnamic acid, chrysin, pinocembrin, 3,5-diprenyl-4-hydroxycinnamic acid and dicaffeoylquinic acid. The negative mode ESI-MS fingerprinting method is capable of discerning distinct composition patterns to typify, to screen the sample origin and to reveal characteristic details of the more polar and acidic chemical components of propolis samples from different regions of the world.

11.
Braz. j. microbiol ; 35(1/2): 104-109, Jan.-Jun. 2004. ilus
Artigo em Inglês | LILACS | ID: lil-388806

RESUMO

Própolis brasileira, proveniente do estado de São Paulo, foi submetida à extração usando vários solventes, resultando em extratos com diferentes composições. Estes extratos foram submetidos à Cromatografia em Camada Delgada (CCD). Análise bioautográfica das placas de CCD permitiu identificar as frações com atividade antimicrobiana, que foram então analisadas por Cromatografia Líquida de Alta Eficiência (CLAE). Ensaios in vitro freqüentemente utilizados para avaliar a atividade de própolis frente a bactérias Gram-positivas foram comparados para determinar qual renderia os resultados mais consistentes. A atividade bactericida destes extratos foi analisada por Diluição Seriada em Tubos e por testes de Difusão em Agar. O método de Diluição em Tubos permitiu obter os resultados mais consistentes e a Concentração Bactericida Mínima dos extratos variou entre 2,5 e 20,0 mg/mL, para as espécies de bactérias Gram-positivas testadas. Os resultados do método de Difusão em Agar foram diretamente proporcionais à hidrossolubilidade dos extratos, e não avaliaram a atividade bactericida corretamente. A atividade bactericida desta amostra resultou da combinação de vários componentes, identificados por CLAE, que foram extraídos preferencialmente usando etanol 50 per center como solvente.


Assuntos
Cromatografia Líquida de Alta Pressão , Cromatografia em Camada Delgada , Técnicas In Vitro , Própole/análise , Métodos
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