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1.
Braz. j. biol ; 84: e249664, 2024. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1345558

ABSTRACT

Abstract The impact of antibiotics on growth, cocoon production was assessed in addition to isolation and characterization of bacteria associated with silkworm gut of infected larvae. Larval rearing was maintained at recommended conditions of temperature and humidity. Silkworm larvae showing abnormal symptoms were collected from the control group and dissected for gut collection. Bacteria were isolated from the gut content by spreading on agar plates and incubated at 37 °C for 48 hrs. Bacterial identification and phylogenetic analysis were carried out by 16S rRNA gene sequencing. The isolated bacteria were subjected to antimicrobial susceptibility test (disc diffusion methods) by using Penicillin (10 µg/mL), Tetracycline (30 µg/mL), Amoxicillin (25 µg/mL), Ampicillin (10 µg/mL), and Erythromycin (15 µg/mL). All isolated strains showed positive results for the catalase test. We isolated and identified bacterial strains (n = 06) from the gut of healthy and diseased silkworm larvae. Based on the 16S rRNA gene sequence, isolated bacteria showed close relation with Serratia, Bacillus, and Pseudomonas spp. Notably, 83.3% of strains were resistant to Penicillin, Tetracycline, Amoxicillin, Ampicillin, and Erythromycin but 16.6% showed antibiotic susceptibility to the above-mentioned commonly used antibiotics. Silkworm larvae fed on penicillin-treated leaves showed significant improvement in larval weight, larval length, and cocoon production. Significantly higher larval weight (6.88g), larval length (5.84cm), and cocoon weight (1.33g) were recorded for larvae fed on leaves treated with penicillin as compared to other antibiotics. Isolated bacterial strains showed close relation with Serratia spp., Bacillus spp. and Pseudomonas spp.


Resumo O impacto dos antibióticos no crescimento e na produção do casulo foi avaliado, além do isolamento e caracterização das bactérias associadas ao intestino de larvas infectadas do bicho-da-seda. A criação das larvas foi mantida nas condições recomendadas de temperatura e umidade. As larvas do bicho-da-seda com sintomas anormais foram coletadas do grupo controle e dissecadas para coleta do intestino. As bactérias foram isoladas do conteúdo intestinal por espalhamento em placas de ágar e incubadas a 37° C durante 48 horas. A identificação bacteriana e a análise filogenética foram realizadas pelo sequenciamento do gene 16S rRNA. As bactérias isoladas foram submetidas a teste de sensibilidade antimicrobiana (métodos de difusão em disco) com penicilina (10 µg / mL), tetraciclina (30 µg / mL), amoxicilina (25 µg / mL), ampicilina (10 µg / mL) e eritromicina (15 µg / mL). Todas as cepas isoladas apresentaram resultados positivos para o teste da catalase. Isolamos e identificamos cepas bacterianas (n = 06) do intestino de larvas de bicho-da-seda saudáveis e doentes. Com base na sequência do gene 16S rRNA, as bactérias isoladas mostraram estreita relação com Serratia, Bacillus e Pseudomonas spp. Notavelmente, 83,3% das cepas eram resistentes a penicilina, tetraciclina, amoxicilina, ampicilina e eritromicina, mas 16,6% mostraram suscetibilidade aos antibióticos comumente usados mencionados acima. As larvas do bicho-da-seda alimentadas com folhas tratadas com penicilina apresentaram melhora significativa no peso larval, comprimento larval e produção de casulo. Peso larval significativamente maior (6,88g), comprimento larval (5,84cm) e peso do casulo (1,33g) foram registrados para larvas alimentadas com folhas tratadas com penicilina, em comparação com outros antibióticos. Cepas bacterianas isoladas mostraram estreita relação com Serratia spp., Bacillus spp. e Pseudomonas spp.


Subject(s)
Animals , Bombyx , Anti-Bacterial Agents/pharmacology , Phylogeny , Bacteria/genetics , RNA, Ribosomal, 16S/genetics , Microbial Sensitivity Tests , Larva
2.
Braz. j. biol ; 83: e243332, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1345537

ABSTRACT

Abstract The present study was aimed to manifest the antibacterial and antifungal activity of methanolic extracts of Salix alba L. against seven Gram-positive and Gram-negative bacterial pathogens e.g. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) and Neisseria gonorrhoeae and three fungal isolates from the air such as Aspergillus terreus, A. ornatus, and Rhizopus stolonifer. Two different serotypes of S. aureus and E. coli were used. The agar well-diffusion method results showed the dose-dependent response of plant extracts against bacterial and fungal strains while some organisms were found resistant e.g. E. coli (1), S. sonnei, A. terreus and R. stolonifer. The highest antibacterial activity was recorded at 17.000±1.732 mm from 100 mg/mL of leaves methanolic extracts against S. pyogenes while the activity of most of the pathogens decreased after 24 h of incubation. The highest antifungal activity was reported at 11.833±1.0 mm against A. ornatus at 50 mg/mL after 48 h of the incubation period. These experimental findings endorse the use of S. alba in ethnopharmacological formulations and suggest the use of methanolic extracts of the said plant to develop drugs to control the proliferation of resistant disease causing pathogenic microbes.


Resumo O presente estudo teve como objetivo manifestar a atividade antibacteriana e antifúngica de extratos metanólicos de Salix alba L. contra sete patógenos bacterianos Gram-positivos e Gram-negativos. Streptococcus pyogenes, Staphylococcus aureus (1), S. aureus (2), Shigella sonnei, Escherichia coli (1), E. coli (2) e Neisseria gonorrhoeae e três isolados de fungos do ar, como Aspergillus terreus, A. ornatus, e Rhizopus stolonifer. Dois sorotipos diferentes de S. aureus e E. coli foram usados. Os resultados do método de difusão em ágar mostraram a resposta dependente da dose de extratos de plantas contra cepas de bactérias e fungos, enquanto alguns organismos foram considerados resistentes, e.g. E. coli (1), S. sonnei, A. terreus e R. stolonifer. A maior atividade antibacteriana foi registrada em 17.000 ± 1.732 de 100 mg/mL de extratos metanólicos de folhas contra S. pyogenes, enquanto a atividade da maioria dos patógenos diminuiu após 24 h de incubação. A maior atividade antifúngica foi relatada em 11,833 ± 1,0 contra A. ornatus a 50 mg/mL após 48 h do período de incubação. Esses achados experimentais endossam o uso de S. alba em formulações etnofarmacológicas e sugerem o uso de extratos metanólicos da referida planta para o desenvolvimento de fármacos que controlem a proliferação de doenças resistentes que causam micróbios patogênicos.


Subject(s)
Salix , Antifungal Agents/pharmacology , Aspergillus , Rhizopus , Staphylococcus aureus , Plant Extracts/pharmacology , Microbial Sensitivity Tests , Methanol , Escherichia coli , Anti-Bacterial Agents/pharmacology
3.
Braz. j. biol ; 83: e249536, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1345531

ABSTRACT

Abstract Seaweeds are a major marine resource that can be explored to develop novel pharmaceutical molecules. The present study showed the presence of unique bioactive components in the petroleum ether extract (PEE) and methanolic extract (ME) of Sargassum tenerrimum. The gas chromatography-mass spectrometry analysis suggested that the PEE of S. tenerrimum contained antibacterial biomolecules: hexadecanoic acid, methyl ester, 17-pentatriacontene, dasycarpidan-1-methanol, and acetate (ester). However, the ME of S. tenerrimum exhibited better antibacterial effect than the PEE due to the presence of the bioactive compounds 1,2-benzenedicarboxylic acid, diisooctyl ester, tetratetracontane, 1-docosene, 1,2-benzenediol, and benzoic acid. Thus, promising antibacterial molecules can be isolated from S. tenerrimum for better therapeutic use.


Resumo As algas marinhas são um importante recurso marinho que pode ser explorado para desenvolver novas moléculas farmacêuticas. O presente estudo mostrou a presença de componentes bioativos únicos no extrato etéreo de petróleo (PEE) e no extrato metanólico (ME) de Sargassum tenerrimum. A análise por cromatografia gasosa-espectrometria de massa sugeriu que o PEE de S. tenerrimum continha biomoléculas antibacterianas: ácido hexadecanoico, éster metílico, 17-pentatriaconteno, dasycarpidan-1-metanol e acetato (éster). Entretanto, o ME de S. tenerrimum exibiu melhor efeito antibacteriano do que o PEE devido à presença dos compostos bioativos ácido 1,2-benzenodicarboxílico, éster diisooctil, tetratetracontano, 1-docosene, 1,2-benzoenodiol e ácido benzoico. Assim, moléculas antibacterianas promissoras podem ser isoladas de S. tenerrimum para melhor uso terapêutico.


Subject(s)
Sargassum , Saudi Arabia , Plant Extracts , Indian Ocean , Anti-Bacterial Agents/pharmacology
4.
Braz. j. biol ; 83: e247016, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339416

ABSTRACT

Abstract Pheretima posthuma (Vaillant, 1868), a native earthworm of Pakistan and Southeast Asia, has wide utilization in vermicomposting and bioremediation process. In this study, P. posthuma coelomic fluid (PCF) and body paste (PBP) was evaluated as antibacterial agent against ampicillin (AMP) resistant five Gram positive and four Gram negative clinical isolates. The antibacterial effect of different doses (i.e. 25-100 µg/ml) of PCF and PBP along with AMP and azithromycin (AZM) (negative and positive controls, respectively) were observed through disc diffusion and micro-dilution methods. All nine clinical isolates were noticed as AMP resistant and AZM sensitive. Antibacterial effects of PCF and PBP were dose dependent and zone of inhibitions (ZI) against all clinical isolates were between 23.4 ± 0.92 to 0 ± 00 mm. The sensitivity profile of PCF and PBP against clinical isolates was noticed as 44.44 and 55.56%, respectively. Both PCF and PBP showed bacteriostatic (BTS) action against S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Moreover, the cumulative BTS potential of PCF and PBP against all isolates was 66.67 and 55.56%, respectively. The MICs of PCF and PBP were ranged from 50-200 µg/ml against selected isolates. The bacterial growth curves indicated that PCF and PBP inhibited the growth of all isolates at their specific MIC concentrations. However, PBP has better antibacterial potential compared to PCF against selected isolates. Therefore, it is concluded that both PCF and PBP of P. posthuma possess antibacterial and BTS potential against ampicillin resistant clinical isolates. This organism might be considered as a second choice of antibacterial agents and can further be utilized in pharmaceutical industries for novel drug manufacturing by prospecting bioactive potential agents.


Resumo Pheretima posthuma (Vaillant, 1868), uma minhoca nativa do Paquistão e sudeste da Ásia, tem ampla utilização em processos de vermicompostagem e biorremediação. Neste estudo, o fluido celômico de P. posthuma (PCF) e a pasta corporal (PBP) foram avaliados como agente antibacteriano contra cinco isolados clínicos Gram-positivos e quatro Gram-negativos resistentes à ampicilina (AMP). O efeito antibacteriano de diferentes doses (ou seja, 25-100 µg / ml) de PCF e PBP juntamente com AMP e azitromicina (AZM) (controles negativo e positivo, respectivamente) foi observado por meio de métodos de difusão em disco e microdiluição. Todos os nove isolados clínicos foram notados como resistentes a AMP e sensíveis a AZM. Os efeitos antibacterianos de PCF e PBP foram dependentes da dose e a zona de inibição (ZI) contra todos os isolados clínicos foi entre 23,4 ± 0,92 a 0 ± 00 mm. O perfil de sensibilidade do PCF e PBP contra isolados clínicos foi observado como 44,44% e 55,56%, respectivamente. Tanto o PCF quanto o PBP mostraram ação bacteriostática (BTS) contra S. aureus, S. pyogenes, K. pneumonia, N. gonorrhoeae. Além disso, o potencial BTS cumulativo de PCF e PBP contra todos os isolados foi de 66,67% e 55,56%, respectivamente. Os MICs de PCF e PBP variaram de 50-200 µg / ml contra isolados selecionados. As curvas de crescimento bacteriano indicaram que o PCF e o PBP inibiram o crescimento de todos os isolados em suas concentrações específicas de MIC. No entanto, PBP tem melhor potencial antibacteriano em comparação com PCF contra isolados selecionados. Portanto, conclui-se que tanto o PCF quanto o PBP de P. posthuma possuem potencial antibacteriano e BTS contra isolados clínicos resistentes à ampicilina. Esse organismo pode ser considerado como uma segunda escolha de agentes antibacterianos e pode ainda ser utilizado nas indústrias farmacêuticas para a fabricação de novos medicamentos por meio da prospecção de agentes com potencial bioativo.


Subject(s)
Animals , Oligochaeta , Staphylococcus aureus , Microbial Sensitivity Tests , Ampicillin/pharmacology , Anti-Bacterial Agents/pharmacology
5.
Braz. j. biol ; 83: e245585, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339413

ABSTRACT

Abstract Many soil microorganisms' i.e., bacteria and fungi produce secondary metabolites called antibiotics. These are used for the treatment of some of the bacterial, fungal and protozoal diseases of humans. There is a need for isolation of a broad spectrum of antibiotics from microorganisms due to the emergence of antibiotic resistance. In the present study two antibiotic producing bacteria Klebsiella pneumoniae and Bacillus cereus were isolated from pharmaceutical and poultry feed industry of Hattar, Haripur Pakistan. Total 10 waste samples were collected from different industries (Marble, Ghee, Soap, Mineral, Steel, Poultry Feed, Pharmaceutical, Qarshi, Cosmetic and Glass). Thirty-three bacterial strains were isolated from industrial wastes of these ten different industries. Fourteen out of thirty-three bacterial strains exhibited antimicrobial activities against at least one of the test microbes considered in this study including Escherchia coli, Staphylococcus aureus and Salmonella typhi. The bacteria were isolated by standard serial dilution spread plate technique. Morphological characterization of the isolates was done by Gram staining. Nine bacterial isolates out of fourteen were initially identified as B. cereus and five as K. pneumoniae through biochemical characterization. The antibacterial activities were tested by well diffusion method. Maximum number of antibiotic producing bacteria were isolated from pharmaceutical and poultry feed industry based on the results of primary screening, the most potential isolates S9, S19, S20, S22 and S23 were selected for secondary screening. The maximum activity against E. coli and S. aureus was recorded by bacterial isolate S19 i.e zones of inhibition of 6.5mm and 9mm while S20 showed 7.5mm and 6mm zones respectively. Molecular identification was carried out on the basis of 16S rRNA sequence analysis. Finally, the isolates were identified as B. cereus accession number LC538271and K. pneumoniae accession number MT078679. Analysis of bacterial extract S20 through GC-MS indicated the presence of 8 compounds of diverse nature and structure. Present study suggests that wastes of pharmaceutical and poultry feed industry may have antibiotic producing bacteria. These bacteria could be utilized for the production of antibiotics. B. cereus and K. pneumoniae isolated from wastes of poultry feed and pharmaceutical industries have the potential to produce antibiotics and could be used to control the microbial growth.


Resumo Muitos microrganismos do solo, ou seja, bactérias e fungos produzem metabólitos secundários chamados antibióticos. Eles são usados ​​para tratamento de algumas doenças bacterianas, fúngicas e protozoárias em humanos. Há necessidade de isolamento de um amplo espectro de antibióticos de microrganismos devido ao surgimento de resistência aos antibióticos. No presente estudo, duas bactérias produtoras de antibióticos, Klebsiella pneumoniae e Bacillus cereus, foram isoladas da indústria farmacêutica e de ração avícola de Hattar, Haripur, Paquistão. Um total de 10 amostras de resíduos foi coletado de diferentes indústrias (mármore, ghee, sabão, mineral, aço, ração para aves, farmacêutica, Qarshi, cosmética e vidro). Trinta e três cepas bacterianas foram isoladas de resíduos industriais dessas dez diferentes indústrias. Quatorze das 33 cepas bacterianas exibiram atividades antimicrobianas contra pelo menos um dos micróbios de teste considerados neste estudo, incluindo Escherchia coli, Staphylococcus aureus e Salmonella typhi. As bactérias foram isoladas pela técnica de placa de diluição em série padrão. A caracterização morfológica dos isolados foi feita por coloração de gram. Nove isolados bacterianos de 14 foram inicialmente identificados como B. cereus e cinco como K. pneumoniae por meio de caracterização bioquímica. As atividades antibacterianas foram testadas pelo método de difusão em poço. O número máximo de bactérias produtoras de antibióticos foi isolado da indústria farmacêutica e de ração avícola com base nos resultados da triagem primária, os isolados mais potenciais S9, S19, S20, S22 e S23 foram selecionados para a triagem secundária. A atividade máxima contra E. coli e S. aureus foi registrada pelo isolado bacteriano S19, ou seja, zonas de inibição de 6,5 mm e 9 mm, enquanto S20 mostrou zonas de 7,5 mm e 6 mm, respectivamente. A identificação molecular foi realizada com base na análise da sequência 16S rRNA. Finalmente, os isolados foram identificados como B. cereus número de acesso LC538271 e K. pneumoniae número de acesso MT078679. A análise do extrato bacteriano S20 por meio de GC-MS indicou a presença de oito compostos de natureza e estrutura diversas. O presente estudo sugere que resíduos da indústria farmacêutica e de ração para aves podem conter bactérias produtoras de antibióticos. Essas bactérias podem ser utilizadas para a produção de antibióticos B. cereus e K. pneumoniae isolados de resíduos de rações de aves e indústrias farmacêuticas têm potencial para produzir antibióticos e podem ser usados ​​para controlar o crescimento microbiano.


Subject(s)
Humans , Staphylococcus aureus , Industrial Waste , RNA, Ribosomal, 16S , Plant Extracts , Microbial Sensitivity Tests , Escherichia coli , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/pharmacology
6.
Braz. j. biol ; 83: e236649, 2023. tab
Article in English | LILACS, VETINDEX | ID: biblio-1339379

ABSTRACT

Abstract Croton argyrophylloides Muell. Arg., from the Euphorbiaceae family, popularly known as marmeleiro prateado or sacatinga, is a plant from the Caatinga biome commonly found in Brazil's northeastern region. The present study aimed to evaluate the antioxidant activity of the species. The phytochemical study was performed through qualitative analysis of chemical constituents and quantitative determination of the total phenol content through the Folin-Ciocalteu test. The qualitative and quantitative antioxidant tests were performed using the DPPH method (2.2 diphenyl-1-picryl hydrazil) and ferric reducing antioxidant power (FRAP). The minimum inhibitory concentration (MIC) was determined by microdilution in 96-well plates. The ethanolic extract of the leaves of C. argyrophylloides manifested antioxidant action in the quantitative DPPH test with a significant bioactivity of 84.70 AAO% in 500 µg/mL, with an EC50 of 236.79. The content of total phenolic compounds was 946.06 mg of gallic acid equivalents/g of sample, and total flavonoids was 58.11 mg of quercetin equivalents/g of sample, the result obtained for FRAP was 15294.44 µM Trolox/g of sample and ABTS was 718 μM Trolox of sample. The prospecting of the chemical constituents of the leaves of C. argyrophylloides revealed the presence of the main compounds that manifests the antioxidant activity and it was proven by the DPPH method that there is antioxidant activity in the analyzed sample, in addition to demonstrating a significant content of phenolic compounds and total flavonoid content in the species, which corroborates the antioxidant activity of the plant sample. The leaf extracts presented growth inhibition halos of 10 and 12 mm upon Staphylococcus aureus ATCC 25923.


Resumo Croton argyrophylloides Muell. Arg., pertencente à família Euphorbiaceae, conhecida popularmente como marmeleiro prateado e sacatinga, é um vegetal do bioma caatinga comumente encontrado no Nordeste do Brasil. O presente trabalho teve como objetivo avaliar a atividade antioxidante da espécie. O estudo fitoquímico foi realizado por meio de análise qualitativa dos constituintes químicos e determinação quantitativa do teor de fenóis totais pelo teste de Folin-Ciocalteu. Os testes antioxidantes qualitativos e quantitativos foram realizados pelo método do DPPH (2,2 difenil-1- picril-hidrazila) e redução do ferro (FRAP). A concentração inibitória mínima (CIM) foi determinada por microdiluição em placas de 96 poços. O extrato etanólico das folhas de C. argyrophylloides apresentou ação antioxidante no teste DPPH quantitativo com uma significativa bioatividade de 84.70 AAO% em 500 µg/mL, apresentando um CE50 de 236.79. O teor de compostos fenólicos totais, foi de 946,06 mg equivalentes de ácido gálico/g de amostra, e de flavonoides totais de 58,11 mg equivalentes de quercetina/g da amostra, o valor encontrado para FRAP foi de 15294,44 µM Trolox/g da amostra e de ABTS foi 718 μM Trolox da amostra. A prospecção dos constituintes químicos das folhas de C. argyrophylloides revelou a presença dos principais compostos que caracterizam a atividade antioxidante e foi possível comprovar pelo método de DPPH que há atividade antioxidante na amostra analisada, além de demonstrar um resultado significativo de teor de compostos fenólicos e teor de flavonoides totais na espécie e o que corrobora com a atividade antioxidante da amostra vegetal. Os extratos das folhas apresentaram halos de inibição de crescimento de 10 e 12mm frente a Staphylococcus aureus ATCC 25923.


Subject(s)
Euphorbiaceae , Croton , Plant Extracts/pharmacology , Phytochemicals , Anti-Bacterial Agents/pharmacology , Antioxidants/pharmacology
7.
Braz. j. biol ; 83: e248063, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1339340

ABSTRACT

Abstract Persea lingue Ness is a tree species that lives mainly in temperate forests of south-central Chile. Its leaves are used in ethnomedicine, the fruit is a drupe similar to that of the avocado and has not been studied. The aim of this study was to determine the cytotoxicity in leukemia cell and antibacterial activity, along with some chemical content characteristics of P. lingue fruit and leaf extracts. The antibacterial activity was determined by the inhibition of bacterial growth in liquid medium assay against Gram-positive and Gram-negative bacteria. The leukemia cell lines Kasumi-1 and Jurkat were used to evaluate the cytotoxic activity by using propidium iodide and AlamarBlue assays. Total phenolic, flavonoid, condensed tannin, alkaloid and lipid contents were evaluated in the fruit and in the leaf extracts. The antioxidant activity of both extracts were also elavaluated. Leaf extract presented the highest content of total phenols, condensed tannins and flavonoids, and also the highest antioxidant activity. While the fruit extract has a higher amount of lipids and alkaloids and the high antibacterial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium and Micrococcus luteus. The leaf extract only showed activity against M. luteus. Concerning the cytotoxic activity, only the fruit extract showed cytotoxicity against the cell lines Jurkat and Kasumi-1. P. lingue fruit extract is a potential source of biologically active molecules for the development of new drugs to be used in some types of leukemia, as well as antibacterial agent.


Resumo Persea lingue Ness é uma árvore que vive principalmente na floresta temperada do centro-sul do Chile. As folhas são usadas na etnomedicina. O fruto é uma drupa similar ao abacate e que nunca foi pesquisada anteriormente. O objetivo deste estudo foi o de avaliar a citotoxicidade em células leucêmicas e as atividades antibacterianas, assim como algumas características químicas do extrato de fruto e da folha do P. lingue. As atividades antibacterianas foram determinadas pelo método da inibição do crescimento bacteriano em meio líquido empregando-se bactérias Gram-positivas e Gram-negativas. As linhagens celulares leucêmicas, Kasumi-1 e Jurkat foram usadas para avaliar a atividade citotóxica em ensaios empregando-se iodeto de propídio e AlamarBlue. Foram avaliados os teores totais de fenóis, flavonóides, taninos condensados, alcalóides e lipídeos presentes nos extratos das folhas e dos frutos. As atividades antioxidantes de ambos os extratos também foram avaliadas. O extrato das folhas foi o que apresentou o maior conteúdo de fenóis, taninos condensados e flavonóides totais e a maior atividade antioxidante. Já o extrato de fruto apresentou a maior quantidade de lipídios e alcaloides e a melhor atividade antibacteriana contra Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, Bacillus megaterium e Micrococcus luteus. Já o extrato das folhas apresentou apenas atividade contra M. luteus. Em relação à atividade citotóxica, apenas o extrato do fruto apresentou citotoxicidade contra as linhagens celulares Jurkat e Kasumi-1. Em resumo, o extrato do fruto de P. lingue é uma potencial fonte de moléculas com atividade biológica para o desenvolvimento de novos fármacos a serem utilizados em alguns tipos de leucemia, bem como agente antibacteriano.


Subject(s)
Lauraceae , Persea , Plant Extracts/pharmacology , Fruit , Gram-Negative Bacteria , Gram-Positive Bacteria , Anti-Bacterial Agents/pharmacology
8.
Braz. j. biol ; 83: e244479, 2023. tab, graf
Article in English | LILACS, VETINDEX | ID: biblio-1285635

ABSTRACT

Abstract The objective of the present study was to analyse the bioactive compounds of the leaves of Conocarpus lancifolius (C. lancifolius). The GC-MS analysis of the hot methanolic extract of the leaves (HMEL) of C. lancifolius exhibited the bioactive compounds such as 1-(3-Methoxy-2-nitrobenzyl) iso quinoline, morphin-4-ol-6,7-dione, 1-bromo-N-methyl-, phytol, hexadecanoic acid, 2,3-dihydroxypropyl ester, 2,2':4',2"-terthiophene, ethyl iso-allocholate, caryophyllene oxide, campesterol, epiglobulol, cholestan-3-ol, 2-methylene-, (3á,5à)-, dasycarpidan-1-methanol, acetate (ester) and oleic acid, eicosyl ester. The FT-IR analysis of HMEL of C. lancifolius showed a unique peak at 3184, 2413, 1657 cm-1 representing coumaric acid, chlorogenic acid and ferulic acid. The HMEL of C. lancifolius was actively inhibiting the proliferation of breast cancer cells MCF-7 ATCC at the concentration of 72.66 ± 8.21 µg/ml as IC50 value. The HMEL of C. lancifolius also revealed a good spectrum of activity against Gram-positive and Gram-negative bacterial cultures screened in this work. The activity observed has shown more or less similar effects against screened bacteria. However, the magnitude of potentiality was significantly lesser compared to standard ciprofloxacin disc at p< 0.001 level (99% confidence intervals). Furthermore, the study demonstrating the bioactive compounds can be isolated from the leaves of C. lancifolius.


Resumo O objetivo do presente estudo foi analisar os compostos bioativos das folhas de Conocarpus lancifolius (C. lancifolius). A análise por GC-MS do extrato metanólico quente das folhas (HMEL) de C. lancifolius exibiu os compostos bioativos como 1- (3-Metoxi-2-nitrobenzil) isoquinolina, morfina-4-ol-6,7- diona, 1-bromo-N-metil-, fitol, ácido hexadecanoico, 2,3-di-hidroxipropil éster, 2,2 ': 4', 2 " - tertiofeno, isoalocolato de etil, óxido de cariofileno, campesterol, epiglobulol, colestano -3-ol, 2-metileno-, (3á, 5à) -, dasycarpidan-1-metanol, acetato (éster) e ácido oleico, éster eicosílico. A análise FT-IR de HMEL de C. lancifolius mostrou um pico único em 3184, 2413, 1657 cm-1 representando ácido cumarico, ácido clorogênico e ácido ferúlico. O HMEL de C. lancifolius inibiu ativamente a proliferação de células de câncer de mama MCF-7 ATCC na concentração de 72,66 ± 8,21 µg / ml como valor de IC50. O HMEL de C. lancifolius também revelou bom espectro de atividade contra culturas de bactérias Gram-positivas e Gram-negativas rastreadas neste trabalho. A atividade observada mostrou efeitos mais ou menos semelhantes contra bactérias rastreadas. No entanto, a magnitude da potencialidade foi significativamente menor em comparação com o disco de ciprofloxacina padrão em nível de p < 0,001 (intervalos de confiança de 99%). Além disso, o estudo demonstrando os compostos bioativos pode ser isolado das folhas de C. lancifolius.


Subject(s)
Trees , Plant Leaves , Saudi Arabia , Plant Extracts/pharmacology , Spectroscopy, Fourier Transform Infrared , Anti-Bacterial Agents/pharmacology
9.
Arq. ciências saúde UNIPAR ; 26(3): 681-692, set-dez. 2022.
Article in Portuguese | LILACS | ID: biblio-1399322

ABSTRACT

Com o avanço da medicina e o aumento do uso de antimicrobianos, a resistência microbiana vem se tornando um problema sério na saúde pública. Para que uma bactéria se torne resistente, são necessários vários fatores, entre eles, o uso indiscriminado e prolongado de antimicrobianos e as resistências intrínsecas e adquiridas. Nesse contexto, o objetivo do trabalho foi explorar os mecanismos de ação dos antimicrobianos, de resistência e a sua importância na saúde pública. Foram utilizadas para a presente pesquisa, as bases de dados Pubmed, Google acadêmico e Scielo. Segundo a Organização Mundial da Saúde define-se resistência ao antibiótico quando o mesmo não produz mais efeito. A inserção cada vez mais frequente de antimicrobianos favorece a resistência, onde provocam uma pressão seletiva sobre os microrganismos, tornando-os resistentes a diversas drogas. O uso indiscriminado de antimicrobianos é o principal fator de resistência microbiana, assim como o uso de antimicrobianos sem exame de cultura e teste de sensibilidade. Neste sentido, conclui-se que é de suma importância a atualização de protocolos que contenham os mecanismos de resistência bacteriana a fim de minimizar o uso indiscriminado de antimicrobianos, assim como capacitar os profissionais da saúde para este problema na saúde pública.


With the advance of medicine and the increase in the use of antimicrobials, microbial resistance has become a serious problem in public health. For a bacterium to become resistant, several factors are necessary, among them, the indiscriminate and prolonged use of antimicrobials and the intrinsic and acquired resistance. In this context, the objective of the work was to explore the mechanisms of action of antimicrobials, resistance and their importance in public health. Pubmed, Google academic and Scielo databases were used for this research. According to the World Health Organization, resistance to antibiotics is defined when it no longer has an effect. The increasingly frequent insertion of antimicrobials favors resistance, where they put selective pressure on microorganisms, making them resistant to various drugs. The indiscriminate use of antimicrobials is the main factor of microbial resistance, as well as the use of antimicrobials without culture examination and sensitivity test. In this sense, it is concluded that it is extremely important to update protocols that contain the mechanisms of bacterial resistance in order to minimize the indiscriminate use of antimicrobials, as well as to train health professionals for this problem in public health.


Con los avances de la medicina y el mayor uso de antimicrobianos, la resistencia microbiana se ha convertido en un grave problema de salud pública. Para que una bacteria se vuelva resistente son necesarios varios factores, entre ellos, el uso indiscriminado y prolongado de antimicrobianos y la resistencia intrínseca y adquirida. En este contexto, el objetivo de este trabajo fue explorar los mecanismos de acción de los antimicrobianos, la resistencia y su importancia en la salud pública. Para esta investigación se utilizaron las bases de datos Pubmed, Google Scholar y Scielo. Según la Organización Mundial de la Salud, la resistencia a un antibiótico se define cuando deja de producir efecto. El uso cada vez más frecuente de antimicrobianos favorece la resistencia, ya que provocan una presión selectiva sobre los microorganismos, haciéndolos resistentes a varios fármacos. El uso indiscriminado de antimicrobianos es el principal factor de resistencia microbiana, así como el uso de antimicrobianos sin pruebas de cultivo y sensibilidad. En este sentido, se concluye que es de suma importancia actualizar los protocolos que contienen los mecanismos de resistencia bacteriana para minimizar el uso indiscriminado de antimicrobianos, así como capacitar a los profesionales de la salud para este problema en la salud pública.


Subject(s)
Public Health , Drug Resistance, Bacterial/drug effects , Bacteria/drug effects , Drug Resistance/drug effects , Drug Resistance, Microbial/drug effects , Pharmaceutical Preparations/analysis , Cell Wall/drug effects , Review , Biofilms/drug effects , Libraries, Digital , Anti-Infective Agents/analysis , Anti-Bacterial Agents/pharmacology
10.
Vitae (Medellín) ; 29(2): 1-11, 2022-05-19. Ilustraciones
Article in English | LILACS, COLNAL | ID: biblio-1393021

ABSTRACT

Background: Methicillin resistance and biofilm-producing Staphylococci are emerging as multidrug-resistant strains narrowing the efficacy of antimicrobial therapy. Although vancomycin is used as the drug of choice to treat such isolates, different studies worldwide have documented the emergence of strains that are intermediately susceptible or resistant to this antibiotic. Objective: The study aimed to determine the minimum inhibitory concentration of vancomycin to methicillin-resistant and biofilm-producing staphylococci isolated from different clinical specimens. Methods: 375 staphylococci isolated from different clinical specimens over one year were included in the study. Biofilm formation was determined by the Tissue culture plate method (TCP), and ica genes were identified by Polymerase Chain Reaction (PCR). Antibiotic susceptibility and methicillin resistance were done following Clinical and Laboratory Standards Institute (CLSI) guidelines. The minimum inhibitory concentration (MIC) of vancomycin in all isolates was determined by the agar dilution method. Results:Among 375 Staphylococci studied, 43% and 57% represented S. aureus and Coagulase-Negative Staphylococci (CNS), respectively. The rate of Methicillin-Resistant S. aureus (MRSA) and Methicillin-Resistant Coagulase Negative Staphylococci (MRCNS) were 81.4% and 66.8% respectively and determined by the disc diffusion method. The most potential antibiotics were tetracycline and chloramphenicol showing sensitivity to more than 90% isolates. The Minimum Inhibitory Concentration (MIC) value of oxacillin for staphylococci ranged from 0.125-32 µg/ml. Oxacillin agar diffusion method showed 51.6% and 79.9% isolates as MRSA and MRCNS, respectively, revealing a very high percentage of S. aureus and CNS isolates as methicillin-resistant. All isolates had susceptible vancomycin MICs that ranged from 0.125-2 µg/ml. Two S. aureus isolated from Central Venous Catheter (CVC) and catheter specimens were detected with intermediate susceptibility to vancomycin. Similarly, three CNS isolated from blood, CVC, and wound/pus (w/p) were intermediately susceptible to vancomycin. Strong biofilm formation was observed in 22.1% of clinical isolates, and the ica gene was detected among 22.9% of isolates. Only one S. aureus detected as a biofilm producer by the TCP method was found to have intermediate susceptibility to vancomycin. Conclusions: The increment in vancomycin MIC among methicillin-resistant and biofilm-producing staphylococci is alarming. Strict control measures to prevent methicillin-resistant isolates spread and routine surveillance for vancomycin-resistant isolates must be incorporated in hospitals to prevent antimicrobial treatment failure


Antecedentes: Los estafilococos resistentes a la meticilina y productores de biopelículas están surgiendo como cepas multirresistentes que reducen la eficacia del tratamiento antimicrobiano. Aunque la vancomicina se utiliza como fármaco de elección para tratar dichos aislados, diferentes estudios realizados en todo el mundo han documentado la aparición de cepas intermedias susceptibles o resistentes a este antibiótico. Objetivo: El estudio tenía como objetivo determinar la concentración mínima inhibitoria de la vancomicina para los estafilococos resistentes a la meticilina y productores de biofilm aislados de diferentes muestras clínicas. Métodos: Se incluyeron en el estudio 375 estafilococos aislados de diferentes muestras clínicas durante un año. La formación de biopelículas se determinó mediante el método de la placa de cultivo de tejidos (TCP), y los genes ica se identificaron mediante la reacción en cadena de la polimerasa (PCR). La susceptibilidad a los antibióticos y la resistencia a la meticilina se realizaron siguiendo las directrices del Clinical and Laboratory Standards Institute (CLSI). La concentración inhibitoria mínima (MIC) de vancomicina en todos los aislados se determinó por el método de dilución en agar. Resultados:Entre los 375 estafilococos estudiados, el 43% y el 57% representaban S. aureus y estafilococos coagulasa-negativos (ECN), respectivamente. La tasa de S. aureus resistente a la meticilina (SARM) y de estafilococos coagulasa negativos resistentes a la meticilina (ECNM) fue del 81,4% y el 66,8%, respectivamente, y se determinó por el método de difusión de discos. Los antibióticos más potenciales fueron la tetraciclina y el cloranfenicol, que mostraron una sensibilidad superior al 90% de los aislados. El valor de la concentración inhibitoria mínima (CIM) de la oxacilina para los estafilococos osciló entre 0,125-32 µg/ml. El método de difusión en agar de la oxacilina mostró que el 51,6% y el 79,9% de los aislados eran SARM y MRCNS, respectivamente, lo que revela que un porcentaje muy elevado de los aislados de S. aureus y CNS son resistentes a la meticilina. Todos los aislados tenían MIC de vancomicina susceptibles que oscilaban entre 0,125-2 µg/ml. Se detectaron dos S. aureus aislados de muestras de catéteres venosos centrales (CVC) y catéteres con una susceptibilidad intermedia a la vancomicina. Del mismo modo, tres S. aureus aislados de sangre, CVC y herida/pus (w/p) fueron intermedianamente susceptibles a la vancomicina. Se observó una fuerte formación de biopelículas en el 22,1% de los aislados clínicos, y se detectó el gen ica en el 22,9% de los aislados. Sólo un S. aureus detectado como productor de biopelículas por el método TCP resultó tener una susceptibilidad intermedia a la vancomicina. Conclusiones: El incremento de la MIC de vancomicina entre los estafilococos resistentes a la meticilina y productores de biofilm es alarmante. Para evitar el fracaso del tratamiento antimicrobiano, deben incorporarse en los hospitales medidas de control estrictas para prevenir la propagación de los aislados resistentes a la meticilina y una vigilancia rutinaria de los aislados resistentes a la vancomicina


Subject(s)
Humans , Vancomycin/pharmacology , Biofilms/drug effects , Methicillin-Resistant Staphylococcus aureus/drug effects , Anti-Bacterial Agents/pharmacology , Microbial Sensitivity Tests , Vancomycin Resistance
11.
Bol. latinoam. Caribe plantas med. aromát ; 21(3): 309-322, mayo 2022. tab
Article in English | LILACS | ID: biblio-1396871

ABSTRACT

This paper describes the evaluation of the antimicrobial and hemolytic activity of the hexane, dichloromethane, ethyl acetate and methanol extracts from seeds and epicarps of Garcinia madruno; as well garcinol, morelloflavone and volkensiflavone isolated from the same species. In the preliminary test of bacterial susceptibility, hexane extracts from seeds and epicarps and the three compounds tested only displayed inhibitory growth effect against Gram-positive bacteria. The minimum inhibitory concentrations of extract and compounds ranging from 86.6 to 1253.4 µg/mL. The hemolytic activity was assessed; however, except for the methanol extract from seeds, none of the samples studied induced hemolysis. Thus, our results suggest that extracts and compounds from G. madruno have the potential to be used in the control of pathologies associated to Gram-positive bacteria. This is the first report of the antimicrobial and hemolytic activity of extracts of different polarity obtained from seeds and epicarps of this edible species.


El presente artículo describe la evaluación de la actividad antimicrobiana y hemolítica de los extractos de hexano, diclorometano, acetato de etilo y metanol, obtenidos de la semilla y el epicarpio de Garcinia madruno; así como de garcinol, morelloflavona y volkensiflavona; aislados de la misma especie. En el ensayo de susceptibilidad bacteriana, tanto el extracto de hexano obtenido a partir de la semilla y el epicarpio, y los tres compuestos aislados, únicamente mostraron actividad inhibitoria del crecimiento contra bacterias Gram-positivas. La concentración mínima inhibitoria presentó valores entre 86.6 y 1253.4 µg/mL. También se estableció la actividad hemolítica; sin embargo, con excepción del extracto metanólico obtenido a partir de las semillas, ninguna de las muestras evaluadas indujo hemólisis. Por lo tanto, los resultados sugieren que los extractos y compuestos de G. madruno tienen el potencial de ser usados en el control de bacterias Gram-positivas asociadas a diversas patologías. Este es el primer reporte de actividad antimicrobiana y hemolítica de extractos de diferente polaridad obtenidos de las semillas y epicarpios de esta especie comestible.


Subject(s)
Plant Extracts/pharmacology , Garcinia/chemistry , Hemolytic Agents/pharmacology , Anti-Bacterial Agents/pharmacology , Seeds/chemistry , Terpenes/analysis , Bacteria/drug effects , Microbial Sensitivity Tests , Biflavonoids/analysis
12.
Vitae (Medellín) ; 29(2): 1-9, 2022-05-19. Ilustraciones
Article in English | LILACS, COLNAL | ID: biblio-1393060

ABSTRACT

BACKGROUND: Propolis has been considered a highly valuable material due to its therapeutic properties. However, in Colombia, the commercialization of propolis is limited not only by low production but also by the little knowledge about its efficient extraction. Therefore, finding an optimal and economical extraction method to obtain propolis is a necessity for beekeepers that would open new possibilities for industrial use and, therefore, for the market. OBJECTIVES:The objective of this study was to evaluate a conventional and ultrasound-assisted extraction method, seeking to obtain the highest yield and a high amount of content of bioactive compounds in propolis extracts. METHODS: The extraction was carried out for three crude propolis from different types of bees: Tetragoniscaangustula or Angelita (ANG), Meliponaeburnea or Melipona(MEL), and Scaptotrigonaspp (SCT). The extracts were characterized by color, pH, visual appearance, solid content, antioxidant capacity, total polyphenol content, and bacterial inhibition capacity. RESULTS: The highest extraction performance was obtained when the ultrasound-assisted method was used, especially for the ANG extract, which in addition to presenting inhibition for gram-negative (E. coli) and gram-positive (S. Aureus) bacteria, had the best antioxidant activity with a value of 545 mg GAE / 100 g of sample and total polyphenol content of 1,884 mg GAE / 100 g of sample. CONCLUSIONS: Ultrasound-assisted extraction can be considered a low-cost alternative to increase the extraction performance of crude propolis, together with its total polyphenol content and antioxidant capacity, without altering its physical properties


ANTECEDENTES: El propóleos ha sido considerado un material de alto valor por sus propiedades terapéuticas. Sin embargo, en Colombia la comercialización de propóleos está limitada no solo por la baja producción sino también por el incipiente conocimiento sobre la extracción eficiente de este. Por ello, encontrar un método de extracción óptimo y económico para la obtención de propóleos es una necesidad para los apicultores que abriría nuevas posibilidades para el uso industrial y por tanto para el mercado. OBJETIVOS: El objetivo de este estudio fue evaluar un método de extracción convencional y asistido por ultrasonido (US) buscando el mayor rendimiento y alto contenido de compuestos bioactivos en extractos de propóleos. MÉTODOS: La extracción se realizó para tres propóleos crudos de diferentes tipos de abejas Tetragonisca angustula o Angelita(ANG), Melipona eburnea o Melipona (MEL) y Scaptotrigona spp (SCT). Todos los extractos se caracterizaron por su color, pH, apariencia visual, contenido de sólidos, capacidad antioxidante, contenido total de polifenoles y capacidad de inhibición bacteriana. RESULTADOS: El mayor rendimiento de extracción se obtuvo cuando se usó el método asistido por ultrasonido y específicamente para el extracto ANG, que además de presentar inhibición para bacterias gram negativas (E. coli) y gram positivas (S. Aureus), tuvo la mejor actividad antioxidante con un valor de 545 mg GAE / 100 g de muestra y contenido total de polifenoles de 1884 mg GAE / 100 g de muestra. CONCLUSIONES: La extracción asistida por ultrasonido puede considerarse una alternativa de bajo costo para aumentar el rendimiento de extracción del propóleos crudo, así como su contenido total de polifenoles y capacidad antioxidante sin alterar sus propiedades físicas


Subject(s)
Humans , Propolis/chemistry , Staphylococcus aureus/drug effects , Escherichia coli/drug effects , Antioxidants/pharmacology , Ultrasonics , Bees , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology
13.
Rev. chil. infectol ; 39(2): 109-116, abr. 2022. ilus, tab
Article in Spanish | LILACS-Express | LILACS | ID: biblio-1388342

ABSTRACT

INTRODUCCIÓN: Existe un incremento de las infecciones por Klebsiella pneumoniae resistente a carbapenémicos (KPRC) en la población pediátrica y los datos epidemiológicos son limitados. OBJETIVOS: Conocer la frecuencia de KPRC en pacientes pediátricos, determinar la actividad in vitro de colistina y detectar el gen mcr-1 en dichos aislados. MATERIALES Y MÉTODOS: Se estudiaron 220 aislados de K. pneumoniae en un hospital pediátrico durante los años 2018 y 2019. La susceptibilidad antimicrobiana se determinó por microdilución en caldo según CLSI y EUCAST. Los genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 y mcr-1 se analizaron mediante reacción de polimerasa en cadena (RPC). RESULTADOS: El 9,5% (n: 21) de los aislados fueron caracterizados como KPRC, donde se observó una resistencia a colistina de 47,6% (10/21) con valores de CIM50 de 2 μg/mL y CIM90 de > 4 μg/mL. En todos los aislados de KPRC se caracterizó el gen blaKPC y no se detectó el gen mcr-1. El perfil de resistencia observado en otros antimicrobianos fue el siguiente: gentamicina 100% (n: 21), ciprofloxacina 100% (n: 21), cotrimoxazol 100% (n: 21) y amikacina 19% (n: 4). Se observó 100% de sensibilidad a tigeciclina y ceftazidima/avibactam. CONCLUSIÓN: Este estudio demuestra un valor significativo de la resistencia a colistina en comparación a ceftazidima/avibactam y tigeciclina.


BACKGROUND: There is an increase of carbapenem-resistant Klebsiella pneumoniae (CRKP) infections in the pediatric population and epidemiological data are limited. Aim: To calculate the frequency of CRKP in pediatric patients, to determine the in vitro activity of colistin and to detect the presence of mcr-1 gene in said isolates. METHODS: 220 isolates of K. pneumoniae were studied in a pediatric hospital between January 2018 and December 2019. Antimicrobial susceptibility was determined by microdilution in broth according to guidelines of CLSI and EUCAST. The genes blaKPC, blaNDM, blaIMP, blaVIM, blaOXA-48 and mcr-1 were detected by polymerase chain reaction (PCR). RESULTS: 9.5% (n: 21) of the isolates were characterized as CRKP, where was observed a resistance to colistin of 47.6% (10/21) with values of MIC50 of 2 μg/mL and MIC90 of ≥ 4 μg/mL. In 100% of CRKP strains the blaKPC gene was detected and the mcr-1 gene was not found. The resistance profile to other antimicrobials was as follow: gentamicin 100% (n: 21), trimethoprim/sulfamethoxazole 100% (n: 21), ciprofloxacin 100% (n: 21), amikacin 19% (n: 4). All of the isolates were sensitive to ceftazidime/avibactam and tigecycline. CONCLUSION: This study demonstrates a significant value of resistance to colistin in pediatric patients compared to other last line antimicrobial such as ceftazidime/avibactam and tigecycline.


Subject(s)
Humans , Child , Klebsiella Infections/drug therapy , Carbapenem-Resistant Enterobacteriaceae , Argentina , Bacterial Proteins/genetics , beta-Lactamases/genetics , Microbial Sensitivity Tests , Carbapenems/pharmacology , Ceftazidime , Colistin/pharmacology , Tigecycline , Hospitals, Pediatric , Klebsiella pneumoniae/genetics , Anti-Bacterial Agents/therapeutic use , Anti-Bacterial Agents/pharmacology
14.
Bol. latinoam. Caribe plantas med. aromát ; 21(1): 81-93, ene. 2022. tab, ilus
Article in English | LILACS | ID: biblio-1372383

ABSTRACT

Escherichia coli is a pathogen associated with infections in piglets in the post-weaning phase, its pathogenicity is related to the animal's susceptibility to bacterial enterotoxins. The objective of the present study was to determine the EOs activity against E. colistrain, in the form planktonic and sessile. Although the Disc-Diffusion tests to determine the Minimum Inhibitory Concentration, do not fully corroborate with the other analyzes of this study, it was noticed bacteria inhibition. The EOs were prepared at 0.4%, 0.8% and 1.0% for tests. The tested EOs were effective against E. coliplanktonic cells (p<0.05). As for the sessile cells, the most significant result was inhibition and 100% sessile cells at the concentration of 1.0% of Cymbopogon citratusEO. Although there was resistance in some treatments, the tested EOs demonstrated inhibition capacity, constituting promising alternatives for the control of E. coli, especially of planktonic cells.


Escherichia coli es un patógeno asociado con infecciones en lechones en la fase posterior al destete, su patogenicidad está relacionada con la susceptibilidad del animal a las enterotoxinas bacterianas. El objetivo del presente estudio fue determinar la actividad de contra E. coli, en la forma planctónico y sésil. Aunque las pruebas de difusión de disco para determinar la concentración inhibitoria mínima, no corroboran completamente con los otros análisis de este estudio, se observó inhibición de la bacteria. Las soluciones basadas en AE se prepararon al 0.4%, 0.8% y 1.0% para pruebas. Los AEs probados fueron efectivos contra las células planctónicas (p<0.05). En cuanto a las células sésiles, el resultado más significativo fue la inhibición y el 100% de las células sésiles a la concentración de 1,0% de Cymbopogon citratus. Aunque hubo resistencia en algunos tratamientos, los AEs probados demostraron capacidad de inhibición, constituyendo alternativas prometedoras para el control de E. coli, especialmente de células planctónicas.


Subject(s)
Animals , Oils, Volatile/pharmacology , Plant Extracts/pharmacology , Escherichia coli/drug effects , Anti-Bacterial Agents/pharmacology , Swine , Oils, Volatile/chemistry , Plant Extracts/chemistry , Microbial Sensitivity Tests , Biofilms/drug effects , Ocimum basilicum , Cymbopogon , Diarrhea/microbiology , Escherichia coli/isolation & purification , Escherichia coli/cytology , Flame Ionization , Gas Chromatography-Mass Spectrometry , Anti-Bacterial Agents/chemistry
15.
Braz. j. biol ; 82: e234476, 2022. tab, graf
Article in English | LILACS | ID: biblio-1153484

ABSTRACT

Abstract The Brazilian Cerrado biome consists of a great variety of endemic species with several bioactive compounds, and Anadenanthera peregrina (L.) Speg is a promising species. In this study, we aimed to perform phytochemical characterization and evaluate the antioxidant and antibacterial activities against Staphylococcus aureus and Escherichia coli of the hydroethanolic extract of A. peregrina stem bark. The barks were collected in the Botanical Garden of Goiânia, Brazil. The hydroethanolic extract was obtained by percolation and subjected to physicochemical screening, total phenolic content estimation, high-performance liquid chromatography (HPLC) fingerprinting, and antioxidant (IC50 values were calculated for the 2,2-diphenyl-1-picrylhydrazyl assay - DPPH) and antibacterial activity determination. The pH of the extract was 5.21 and density was 0.956 g/cm3. The phytochemical screening indicated the presence of cardiac glycosides, organic acids, reducing sugars, hemolytic saponins, phenols, coumarins, condensed tannins, flavonoids, catechins, depsides, and depsidones derived from benzoquinones. The extract showed intense hemolytic activity. The total phenolic content was 6.40 g GAE 100 g-1. The HPLC fingerprinting analysis revealed the presence of gallic acid, catechin, and epicatechin. We confirmed the antioxidant activity of the extract. Furthermore, the extract did not inhibit the growth of E. coli colonies at any volume tested, but there were halos around S. aureus colonies at all three volumes tested. These results contribute to a better understanding of the chemical composition of A. peregrina stem bark and further support the medicinal applications of this species.


Resumo O bioma Cerrado brasileiro apresenta em uma grande variedade de espécies endêmicas com diversos compostos bioativos, e Anadenanthera peregrina (L.) Speg é uma espécie promissora. Neste estudo, objetivamos realizar a caracterização fitoquímica e avaliar as atividades antioxidantes e antibacterianas contra Staphylococcus aureus e Escherichia coli do extrato hidroetanólico de cascas do caule de A. peregrina. As cascas foram coletadas no Jardim Botânico de Goiânia, Brasil. O extrato hidroetanólico foi obtido por percolação e submetido a triagem físico-química, estimativa de conteúdo fenólico total, impressão digital por cromatografia líquida de alta eficiência (HPLC) e determinação da atividade antioxidante (valores de IC50 foram calculados para o ensaio 2,2-difenil-1-picril-hidrazil) e antibacteriana. O pH do extrato foi de 5,21 e a densidade foi de 0,956 g/cm3. A triagem fitoquímica indicou a presença de glicosídeos cardíacos, ácidos orgânicos, açúcares redutores, saponinas hemolíticas, fenóis, cumarinas, taninos condensados, flavonóides, catequinas, depsídios e depsidonas derivados de benzoquinonas. O extrato mostrou intensa atividade hemolítica. O conteúdo fenólico total foi de 6,40 g de GAE 100 g-1. A análise por impressão digital por HPLC revelou a presença de ácido gálico, catequina e epicatequina. Confirmamos a atividade antioxidante do extrato. Além disso, o extrato não inibiu o crescimento de colônias de E. coli em nenhum volume testado, mas houve halos em torno das colônias de S. aureus nos três volumes testados. Estes resultados contribuem para uma melhor compreensão da composição química da casca de A. peregrina e apoia ainda mais as aplicações medicinais desta espécie.


Subject(s)
Plant Bark , Antioxidants/pharmacology , Staphylococcus aureus , Brazil , Plant Extracts/pharmacology , Escherichia coli , Phytochemicals , Anti-Bacterial Agents/pharmacology
16.
Braz. j. biol ; 82: e231838, 2022. tab, graf
Article in English | LILACS | ID: biblio-1153467

ABSTRACT

Abstract Use of antibiotics inevitably leads to antimicrobial resistance. Selection for resistance occurs primarily within the gut of humans and animals as well as in the environment through natural resistance and residual antibiotics in streams and soil. We evaluated antimicrobial resistance in Gram negative bacteria from a river system in a rural community in Bahia, Brazil. Water was collected from the Jiquiriçá and Brejões rivers and the piped water supply. Additionally, stools were collected from a random sample of residents, cows, pigs and horses near the river. The samples were screened for bacteria resistant to ciprofloxacin, cefotaxime, and meropenem and identified biochemically at the genus and species levels. Microbial source tracking demonstrated that ruminant and human fecal contamination increased as the rivers neared the village center and decreased after the last residence. Antibiotic bacteria were identified from all samples (n = 32). No bacteria were resistant to carbapenems, but the majority of the enterobacteria were resistant to ciprofloxacin, even though this class of antibiotics is not commonly used in food animals in this region. Considering these facts, together with the pattern of human fecal contamination, a human source was considered most likely for these resistant isolates.


Resumo O uso de antibióticos inevitavelmente leva à resistência antimicrobiana. A seleção para resistência antimicrobiana ocorre principalmente no intestino de seres humanos e animais, bem como no meio ambiente, através da resistência natural e resíduos de antibióticos nos esgotos e no solo. Avaliamos a resistência antimicrobiana em bactérias Gram-negativas de um sistema fluvial em uma comunidade rural da Bahia, Brasil. A água foi coletada nos rios Jiquiriçá e Brejões e no abastecimento de água encanada. Além disso, foram coletadas amostras randomizadas de fezes de moradores, vacas, porcos e cavalos próximos ao rio. As amostras foram triadas para bactérias resistentes à ciprofloxacina, cefotaxima e meropenem e identificadas bioquimicamente nos níveis de gênero e espécie. O rastreamento de fontes microbianas demonstrou que a contaminação fecal de ruminantes e humanos aumentou à medida que os rios se aproximavam do centro da vila e diminuía após a última residência. Bactérias resistentes a antibióticos foram identificadas em todas as amostras (n = 32). Nenhuma bactéria demonstrou ser resistente aos carbapenêmicos testados, contudo, foi encontrado enterobactérias resistentes à ciprofloxacina, ainda que essa classe de antibióticos não seja comumente usada na medicina veterinária dos animais dessa região. Considerando esses fatos, juntamente com o padrão de contaminação fecal avaliado, a fonte de contaminação humana foi considerada a mais provável na interação desses isolados resistentes.


Subject(s)
Humans , Animals , Rivers , Anti-Bacterial Agents/pharmacology , Rural Population , Swine , Brazil , Cattle , Microbial Sensitivity Tests , Drug Resistance, Bacterial
17.
Braz. j. biol ; 82: e232434, 2022. tab, graf
Article in English | LILACS | ID: biblio-1153465

ABSTRACT

Abstract Many pathogenic strains have acquired multidrug-resistant patterns in recent a year, which poses a major public health concern. The growing need for effective antimicrobial agents as novel therapies against multidrug-resistant pathogens has drawn scientist attention toward nanotechnology. Silver nanoparticles are considered capable of killing multidrug-resistant isolates due to their oligo-dynamic effect on microorganisms. In this research study NPs were synthesized using the gram-positive bacteria Lactobacillus bulgaricus and its activity against selected pathogenic strains. Lactobacillus bulgaricus pure cultures were isolated from raw milk and grown in "De Man, Rogasa, and Sharp" broth for synthesis of nanoparticles. Lactobacillus bulgaricus culture was centrifuged and Cell- free supernatant of it was employed with aqueous silvery ions and evaluated their antibacterial activities against bacterial strains i.e. Staphylococcus aureus, Staphylococcus epidermidis and Salmonella typhi using agar well diffusion assay. Antibiotic profiling against selected pathogenic strains were also conducted using disc diffusion method. The synthesis and characterization of silver nanoparticles were monitored primarily by the conversion of the pale-yellow color of the mixture into a dark-brown color and via ultraviolet-visible absorption spectroscopy and Scanning electron microscopy respectively. The result showed that that AgNPs with size (30.65-100 nm) obtained from Lactobacillus bulgaricus were found to exhibit antibacterial activities against selected bacterial strains. Taken together, these findings suggest that Lactobacillus bulgaricus has great potential for the production of AgNPs with antibacterial activities and highly effective in comparison to tested antibiotics.


Resumo Muitas cepas patogênicas adquiriram padrões multirresistentes nos últimos anos, o que representa um grande problema de saúde pública. A crescente necessidade de agentes antimicrobianos eficazes como novas terapias contra patógenos multirresistentes atraiu a atenção dos cientistas para a nanotecnologia. As nanopartículas de prata são consideradas capazes de matar isolados multirresistentes por causa de seu efeito oligodinâmico em microrganismos. Neste estudo de pesquisa, as NPs foram sintetizadas usando a bactéria Gram-positiva Lactobacillus bulgaricus e sua atividade contra cepas patogênicas selecionadas. Culturas puras de Lactobacillus bulgaricus foram isoladas do leite cru e cultivadas em caldo "De Man, Rogasa e Sharp" para síntese de nanopartículas. A cultura de Lactobacillus bulgaricus foi centrifugada, e o sobrenadante livre de células foi empregado com íons prateados aquosos, avaliando-se suas atividades antibacterianas contra cepas bacterianas, isto é, Staphylococcus aureus, Staphylococcus epidermidis e Salmonella typhi usando ensaio de difusão em poço de ágar. O perfil de antibióticos contra cepas patogênicas selecionadas também foi conduzido usando o método de difusão em disco. A síntese e a caracterização das nanopartículas de prata foram monitoradas principalmente pela conversão da cor amarelo-pálida da mistura em uma cor marrom-escura e por espectroscopia de absorção visível e ultravioleta e por microscopia eletrônica de varredura, respectivamente. O resultado mostrou que AgNPs com tamanho de 30,65-100 nm, obtidas de Lactobacillus bulgaricus, exibiram atividades antibacterianas contra cepas bacterianas selecionadas. Tomados em conjunto, esses achados sugerem que o Lactobacillus bulgaricus tem um grande potencial para a produção de AgNPs com atividades antibacterianas e altamente eficazes em comparação aos antibióticos testados.


Subject(s)
Lactobacillus delbrueckii , Metal Nanoparticles , Anti-Infective Agents , Silver/pharmacology , Microbial Sensitivity Tests , Anti-Bacterial Agents/pharmacology
18.
Evid. actual. práct. ambul ; 25(3): e002144, 2022. tab
Article in Spanish | LILACS, BINACIS, UNISALUD | ID: biblio-1398442

ABSTRACT

Lograr un adecuado nivel de anticoagulación con antagonistas orales de la vitamina K suele ser un desafío frecuente en la práctica clínica, dado que su estrecho rango terapéutico suele verse afectado por diversas interacciones farmacológicas,alimentos y condiciones clínicas. A partir de un caso de un paciente anticoagulado que presenta una hemorragia gastro-intestinal posterior a realizar un tratamiento antibiótico, la autora de este artículo revisó la evidencia sobre el riesgo desangrado secundario a la interacción entre este tipo de anticoagulantes y antibióticos orales. Su conclusión tras realizar una búsqueda bibliográfica y seleccionar la mejor evidencia disponible, es que existe un aumento del riesgo relativo desangrado en pacientes anticoagulados que reciben antibióticos, por lo que deberían evitarse aquellos antibióticos con conocido potencial de interacción. Si ello no fuera posible, se recomienda monitorizar el estado de anticoagulación con dosaje de la razón internacional normatizada (RIN) posterior a la introducción del antibiótico. (AU)


Achieving an adequate level of anticoagulation with oral vitamin K antagonists is often a frequent challenge in clinical practice, given that their narrow therapeutic range is often affected by various drug interactions, food, and clinical conditions. Based on a case of an anticoagulated patient who presented gastrointestinal bleeding after antibiotic treatment, the authorof this article reviewed the evidence on the risk of secondary bleeding due to the interaction between this type of anticoagulants and oral antibiotics. Their conclusion, after performing a literature search and selecting the best available evidence, is that there is an increased relative risk of bleeding in anticoagulated patients receiving antibiotics, so antibiotics with known potential for interaction should be avoided. If it weren't possible, it is recommended to monitor the anticoagulation status with International Normalized Ratio (INR) dosing after the introduction of the antibiotic. (AU)


Subject(s)
Humans , Male , Female , Adult , Middle Aged , Aged , Aged, 80 and over , Young Adult , Vitamin K/antagonists & inhibitors , Warfarin/adverse effects , Hemorrhage/chemically induced , Acenocoumarol/adverse effects , Anti-Bacterial Agents/adverse effects , Anticoagulants/adverse effects , Warfarin/pharmacology , Warfarin/pharmacokinetics , Risk Factors , Risk Assessment , International Normalized Ratio , Drug Interactions , Acenocoumarol/pharmacology , Acenocoumarol/pharmacokinetics , Anti-Bacterial Agents/pharmacology , Anticoagulants/pharmacology , Anticoagulants/pharmacokinetics
19.
Braz. J. Pharm. Sci. (Online) ; 58: e19898, 2022. tab, graf
Article in English | LILACS | ID: biblio-1394061

ABSTRACT

Abstract A study was carried out to synthesize silver nanoparticles (Ag-NPs) using plant extracts and to explore their pharmaceutical application as antibacterial agents. Dried leaves of Mentha arvensis Linn. were powdered and extracts were prepared using three different organic solvents. Preliminary screening on antibacterial activity by agar well diffusion method indicated that the methanolic extract possessed higher potential than the other two. Phytochemical analysis of the leaf extract revealed that it possesses tannins, steroids, terpenoids and flavonoids. Ag-NPs prepared using this extract were of spherical to cuboidal shape ranging in size from 40 to 70 nm. It retained essential chemical groups and had the required surface plasmon resonance. Further to the antimicrobial assay, the Ag-NPs, in contrast to the whole methanolic leaf extract, showed better (100% vs. 80%) bactericidal activity against the indicator organisms. The zones of growth inhibition for gram positive bacteria ranged between 14±0.6 and 23±0.3, while it was between 12±0.6 and 22±0.2 for gram negative bacteria. The Ag-NPs presented the minimum inhibitory concentration values of 250 µg/mL for gram positive bacteria and 250 - 500 µg/mL for gram negative bacteria. These findings suggest that the natural compounds present in M. arvensis L. possess the potency to facilitate the synthesis and antibacterial action of Ag-NPs.


Subject(s)
Silver , Plant Extracts/adverse effects , Mentha/adverse effects , Nanoparticles/analysis , Anti-Bacterial Agents/pharmacology , In Vitro Techniques/instrumentation , Pharmaceutical Preparations/analysis , Phytochemicals/administration & dosage , Gram-Negative Bacteria/classification , Gram-Positive Bacteria/classification
20.
Article in English | WPRIM | ID: wpr-939918

ABSTRACT

Four new diphenyl ethers, named epicoccethers K-N (1-4), were purified from the fermentation medium of a fungus Epicoccum sorghinum derived from Myoporum bontioides, and identified through HR-ESI-MS and NMR spectral analysis. Except that compound 1 showed moderate antifungal activity against Penicillium italicum and Fusarium graminearum, the other three compounds showed stronger activity against them than triadimefon. All of them showed moderate or weak antibacterial activity towards Staphylococcus aureus and Escherichia coli with O6 and O78 serotypes except that 3 was inactive to E. coli O6.


Subject(s)
Anti-Bacterial Agents/pharmacology , Antifungal Agents/chemistry , Ascomycota , Escherichia coli , Microbial Sensitivity Tests , Molecular Structure , Phenyl Ethers/chemistry
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