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1.
Int J Microbiol ; 2023: 4026440, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38144901

RESUMO

Punica granatum Linn has been known for its nutritional and medicinal value since ancient times and is used in the treatment of various pathologies owing to its antibacterial properties. This review reports the results of the most recent studies on the antibacterial effects of P. granatum and its isolated compounds on bacteria of clinical interest. A search in the PubMed, Scopus, Science Direct, and Science Citation Index Expanded (Web of Science) databases was performed, which included articles that evaluated the antibacterial activity of P. granatum extracts and excluded articles that analyzed other microorganisms or nonpathogenic bacteria, as well as theses, dissertations, duplicate articles, and those not fully available. The literature suggests that P. granatum extracts can act on bacteria, such as methicillin-sensitive Staphylococcus aureus (MSSA), methicillin-resistant S. aureus (MRSA), Streptococcus mutans, Escherichia coli, Pseudomonas aeruginosa, and Klebsiella pneumoniae. In addition, fruit peel was the most commonly used pharmacogen and methanol, ethanol, and water were the most common solvents for the extraction of bioactive compounds. The antibacterial potential of the methanolic extract of pomegranate peel could be attributed to the presence of active compounds, such as 5-hydroxymethylfurfural, punicic acid, gallic acid, and punicalagin. Thus, there is evidence that these plant extracts, having high polyphenol content, can disrupt the bacterial plasma membrane and inhibit the action of proteins related to antimicrobial resistance. P. granatum shows antibacterial activity against Gram-positive and Gram-negative bacteria, with great potential against multidrug-resistant strains. Further research is needed to clarify the mechanism of action related to this biological activity and investigate the isolated substances that may be responsible for the antibacterial effects.

2.
Metabolites ; 13(9)2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37755307

RESUMO

Leishmaniasis is caused by protozoans of the genus Leishmania, and its treatment is highly toxic, leading to treatment discontinuation and the emergence of resistant strains. In this study, we assessed the leishmanicidal activity and chemical composition of red propolis collected from the Amazon-dominated region of northern Tocantins State, Brazil. The MTT assay was employed to determine the samples' activity against Leishmania amazonensis promastigotes and their cytotoxicity against RAW macrophages. Spectrophotometric assays were utilised to measure the concentrations of total phenolics and flavonoids, while high-performance liquid chromatography coupled to a mass spectrometer (LC-MS/MS) was used to determine the chemical composition. An in silico study was conducted to evaluate which compounds from Brazilian Amazon red propolis may correlate with this biological activity. Brazilian Amazon red propolis exhibited a high concentration of phenolic compounds and an inhibitory activity against L. amazonensis, with an IC50 ranging from 23.37 to 36.10 µg/mL. Moreover, fractionation of the propolis yielded a fraction with enhanced bioactivity (16.11 µg/mL). Interestingly, neither the propolis nor its most active fraction showed cytotoxicity towards macrophages at concentrations up to 200 µg/mL. The red colour and the presence of isoflavonoid components (isoflavones, isoflavans, and pterocarpans) confirm that the substance is Brazilian red propolis. However, the absence of polyprenylated benzophenones suggests that this is a new variety of Brazilian red propolis. The in silico study performed with two of the main leishmanicidal drug targets using all compounds identified in Amazon red propolis reported that liquiritigenin was the compound that exhibited the best electronic interaction parameters, which was confirmed in an assay with promastigotes using a standard. The findings indicate that Amazon red propolis possesses leishmanicidal activity, low toxicity, and significant biotechnological potential.

3.
Artigo em Inglês | MEDLINE | ID: mdl-37191780

RESUMO

As resistance to conventional antibiotics among bacteria continues to increase, researchers are increasingly focusing on alternative strategies for preventing and treating bacterial infections, one of which is microbiota modulation. The objective of this review is to analyze the scientific literature on the immunomodulatory effects of probiotics in bacterial infections. This is an integrative review of the literature based on systematic steps, with searches performed in the databases Medline, PubMed, Scopus, Embase, and ScienceDirect. The most prevalent bacterial genera used to evaluate infectious processes were Salmonella, Escherichia, Klebsiella, and Streptococcus. Lactobacillus was the most commonly used probiotic genus, with Lactobacillus delbrueckii subsp. bulgaricus is the most frequently used species. In most studies, prophylactic treatment with concentrations of probiotics equal to or greater than 8 log CFU/mL was chosen. However, there was considerable heterogeneity in terms of effective treatment duration, indicating that the results cannot be generalized across all studies. This review found that probiotics interact with the immune system through different mechanisms and have a positive effect on preventing different types of bacterial infections.

4.
Rev. epidemiol. controle infecç ; 12(1): 21-31, jan.-mar. 2022. ilus
Artigo em Inglês, Português | LILACS | ID: biblio-1417220

RESUMO

Background and objectives: understanding the clinical-epidemiological and environmental factors related to deaths due to COVID-19 and their distribution in space can serve as subsidies to direct and implement more effective health actions for vulnerable populations. Thus, the objective was to synthesize the scientific evidence related to risk factors and spatial distribution of deaths due to COVID-19 in the world. Content: this is an integrative literature review, and the following guiding question emerged: what is the scientific evidence related to risk factors and spatial distribution of deaths due to COVID-19 in the world? Searches were carried out in the Scientific Electronic Library Online (SciELO) and the Scopus, Web of Science and National Library of Medicine (PubMed) databases in June 2021. Original studies in Portuguese, English or Spanish, without time frame, excluding studies with a specific age group or with an audience with specific comorbidity, were used. A total of 25 studies were included, with findings in different scenarios around the world. Factors such as age, sex, pre-existing diseases were associated with deaths due to COVID-19, which had a heterogeneous spatial distribution and occurred in environmental, socioeconomic and geographic conditions peculiar to these territories. Conclusion: age equal to or greater than 60 years, males, cardiovascular diseases, diabetes mellitus and geographic areas with greater environmental pollution, greater population density and precarious sanitary conditions influenced the mortality of COVID-19.(AU)


Justificativa e objetivos: compreender os fatores clínico-epidemiológicos e ambientais relacionados aos óbitos por COVID-19 e sua distribuição no espaço pode servir de subsídio para direcionar e implementar ações de saúde mais efetivas para populações vulneráveis. Assim, o objetivo foi sintetizar as evidências científicas relacionadas aos fatores de risco e distribuição espacial dos óbitos por COVID-19 no mundo. Conteúdo: trata-se de uma revisão integrativa da literatura, e emergiu a seguinte questão norteadora: quais são as evidências científicas relacionadas aos fatores de risco e distribuição espacial dos óbitos por COVID-19 no mundo? As buscas foram realizadas nas bases de dados Scientific Electronic Library Online (SciELO) e Scopus, Web of Science e National Library of Medicine (PubMed) em junho de 2021. Estudos originais em português, inglês ou espanhol, sem recorte temporal, excluindo estudos com faixa etária específica ou com um público com comorbidade específica. Um total de 25 estudos foram incluídos, com achados em diferentes cenários ao redor do mundo. Fatores como idade, sexo, doenças pré-existentes foram associados aos óbitos por COVID-19, que tiveram distribuição espacial heterogênea e ocorreram em condições ambientais, socioeconômicas e geográficas peculiares a esses territórios. Conclusão: idade igual ou superior a 60 anos, sexo masculino, doenças cardiovasculares, diabetes mellitus e áreas geográficas com maior poluição ambiental, maior densidade populacional e condições sanitárias precárias influenciaram na mortalidade por COVID-19.(AU)


Justificación y objetivos: comprender los factores clínico-epidemiológicos y ambientales relacionados con las muertes por COVID-19 y su distribución en el espacio puede servir como subsidio para orientar e implementar acciones de salud más efectivas para poblaciones vulnerables. Así, el objetivo fue sintetizar la evidencia científica relacionada con los factores de riesgo y la distribución espacial de las muertes por COVID-19 en el mundo. Contenido: se trata de una revisión integrativa de la literatura, y surgió la siguiente pregunta orientadora: ¿cuál es la evidencia científica relacionada con los factores de riesgo y la distribución espacial de las muertes por COVID-19 en el mundo? Las búsquedas se realizaron en las bases de datos Scientific Electronic Library Online (SciELO) y Scopus, Web of Science y National Library of Medicine (PubMed) en junio de 2021. Estudios originales en portugués, inglés o español, sin marco de tiempo, excluyendo estudios con se utilizó un grupo de edad específico o con un público con comorbilidad específica. Se incluyeron un total de 25 estudios, con hallazgos en diferentes escenarios alrededor del mundo. Factores como la edad, el sexo, las enfermedades preexistentes se asociaron a las muertes por COVID-19, que tuvo una distribución espacial heterogénea y se produjo en condiciones ambientales, socioeconómicas y geográficas propias de estos territorios. Conclusión: la edad igual o mayor a 60 años, la maldad, las enfermedades cardiovasculares, la diabetes mellitus y las áreas geográficas con mayor contaminación ambiental, mayor densidad poblacional y precarias condiciones sanitarias influyeron en la mortalidad por COVID-19.(AU)


Assuntos
Humanos , Fatores de Risco , Análise Espacial , COVID-19/mortalidade
5.
Acta amaz ; 46(3): 315-322, 2016. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1455306

RESUMO

Geopropolis, a mixture of plant resin, wax, soil and salivary secretion, is produced by the stingless bee Melipona fasciculata. This aim of this study was to investigate the chemical composition and antioxidant activity of geopropolis collected from beehives in two phytogeographical regions, flooded fields and cerrado, in the municipalities of Palmeirândia and Fernando Falcão, Maranhão State, northeastern Brazil. The geopropolis compounds were identified by gas chromatography-mass spectrometry (GC/MS). Additionally, total phenolic content was determined with the FolinCiocalteu reagent and antioxidant activity was evaluated in vitro by 2,2-diphenyl-1-picrylhydrazyl (DPPH) and ferric reducing antioxidant power (FRAP) assays. The four geopropolis samples varied in terms of total phenolic content and antioxidant activity and the highest values were observed for geopropolis from Fernando Falcão. Triterpenes such as cycloartane, ursane and oleanane and phenolic acids (protocatechuic acid and gallic acid) were identified in the geopropolis from Palmeirândia, while the phenolic acids, gallic and ellagic acid were the main compounds in geopropolis from Fernando Falcão. The antioxidant property of geopropolis is due to its high total phenolic content and predominance of gallic acid and ellagic acid. The results showed that the plant resources in two phytogeographical regions of Maranhão used by bees for the production of geopropolis contribute to the chemical composition and bioactivity of this product.


Geoprópolis, uma mistura de resinas vegetais, cera, terra e secreção salivar, produzida pela abelha sem ferrão Melipona fasciculata. Este estudo investigou a composição química e a atividade antioxidante da geoprópolis coletada em colmeias em duas regiões fitogeográficas de campos alagados e de cerrado, nos municípios de Palmeirândia e Fernando Falcão, no Estado do Maranhão, Nordeste do Brasil. Os compostos da geoprópolis foram identificados por cromatografia gasosa acoplada a espectrometria de massas (CG/EM). Foram determinados os teores de fenólicos totais pelo reagente de FolinCiocalteu, e atividade antioxidante utilizando o ensaio in vitro com 2,2-difenil-1-picrilhidrazil (DPPH) e capacidade redutora do ferro (FRAP). As quatro amostras de geoprópolis apresentaram variações no teor de fenólicos totais e atividade antioxidante, as geoprópolis de Fernando Falcão, apresentaram maiores teores. Nas geoprópolis do município de Palmeirândia foram identificados, triterpenos do tipo cicloartano, ursano e oleanano e ácidos fenólicos (ácido protocatecuico e ácido gálico), enquanto que na geoprópolis de Fernando Falcão, ácidos fenólicos, ácido gálico e elágico foram os principais constituintes. A propriedade antioxidante da geoprópolis pode ser atribuída aos altos teores de fenólicos totais e de ácido gálico e elágico. Os resultados demonstram que as fontes vegetais das duas regiões fitogeográficas do Maranhão, Brasil, utilizadas pelas abelhas para a produção da geoprópolis contribuem para a composição química e bioatividade deste produto.


Assuntos
Polifenóis/análise , Polifenóis/química , Triterpenos , Abelhas , Cromatografia Gasosa-Espectrometria de Massas
6.
J Agric Food Chem ; 62(12): 2549-57, 2014 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-24571707

RESUMO

Geopropolis is a mixture of plant resins, waxes, and soil produced by the stingless bee Melipona fasciculata Smith. This paper describes the antioxidant activity and chemical composition of geopropolis produced by M. fasciculata. The total phenolic content determined with the Folin-Ciocalteu reagent was highest in the ethyl acetate fraction and hydroalcoholic extract. Antioxidant activity was assayed by the in vitro DPPH, ABTS, and FRAP assays. The hydroalcoholic extract and fractions of geopropolis, except for the hexane fraction, exhibited antioxidant activity against DPPH, ABTS, and FRAP. The phenolic compounds were identified by HPLC-DAD-MS on the basis of the evaluation of their UV-vis absorption maxima (λmax) and mass spectral analysis. Eleven compounds belonging to the classes of phenolic acids and hydrolyzable tannins (gallotannins and ellagitannins) were tentatively identified. These compounds are responsible for the antioxidant activity and high phenolic content of geopropolis produced by M. fasciculata.


Assuntos
Antioxidantes/análise , Abelhas/metabolismo , Taninos Hidrolisáveis/análise , Hidroxibenzoatos/análise , Própole/química , Animais , Antioxidantes/metabolismo , Abelhas/química , Cromatografia Líquida de Alta Pressão , Taninos Hidrolisáveis/metabolismo , Hidroxibenzoatos/metabolismo , Espectrometria de Massas , Própole/metabolismo
7.
Rev. bras. farmacogn ; 18(4): 557-562, Oct.-Dec. 2008. ilus, tab
Artigo em Português | LILACS | ID: lil-509049

RESUMO

Melipona fasciculata Smith é uma abelha nativa, social e sem ferrão que produz cera, mel e geoprópolis. O presente trabalho objetivou caracterizar, do ponto de vista farmacognóstico, o geoprópolis de Melipona fasciculata, coletado em meliponários nos municípios de Arari, São Bento e São João Batista, da Baixada maranhense, no Estado do Maranhão, visando estabelecer dados para o controle de qualidade e padronização do produto. A metodologia utilizada constou de análises sensoriais, abordagem química, perfis cromatográficos e determinação dos teores de flavonóides. Os resultados demonstram que o geoprópolis apresenta características sensoriais similares às encontradas para própolis de Apis mellifera, presença de compostos fenólicos em maior concentração, além de substâncias da classe dos terpenos e saponinas e ausência de alcalóides. Os perfis cromatográficos indicaram que a composição e concentração das substâncias químicas são diferentes entre as amostras. Os teores de flavonóides variaram de 0,17 - 2,6%, os quais para a maioria das amostras apresentaram valores acima do mínimo exigido pela legislação brasileira para própolis de Apis mellifera. Os dados encontrados sugerem que as variações qualitativa e quantitativa de flavonóides e outros constituintes químicos no geoprópolis são fortemente afetados pela flora visitada pelas abelhas, região geográfica e fatores ambientais.


Melipona fasciculata Smith is a native, social, stingless bee species that produces wax, honey and geopropolis. This work aimed to do a pharmacological evaluation of Melipona fasciculata geopropolis, collected in beehives in the municipal districts of Arari, São Bento and São João Batista, in Baixada maranhense, in the state of Maranhão, Brazil, seeking to obtain basis for the quality control and standardization of the product. The methodology used included the accomplishment of sensorial analyses, chemical approach, chromatographic profiles and determination of the flavonoids contents. The results demonstrate that the geopropolis have organoleptic characteristics similar to the ones found for the propolis of Apis mellifera, presence of phenolic compounds in larger concentration, besides substances of the class of the terpenes and saponins and absence of alkaloids. The chromatographic profiles indicated that the composition and concentration of the chemical substances are different among the samples. The flavonoids contents ranged between 0.17 - 2.6%. The content for most of the samples presented values above the minimum demanded by the Brazilian legislation for propolis of Apis mellifera. The found data suggest that the qualitative and quantitative variations of flavonoids and other chemical substances in geopropolis are strongly affected for the flora visited by the bees, geographical area and environmental factors.

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