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1.
Braz. j. biol ; 84: e249664, 2024. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345558

RESUMO

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.


Assuntos
Animais , Bombyx , Antibacterianos/farmacologia , Filogenia , Bactérias/genética , RNA Ribossômico 16S/genética , Testes de Sensibilidade Microbiana , Larva
2.
Braz. j. biol ; 83: e243332, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345537

RESUMO

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.


Assuntos
Salix , Antifúngicos/farmacologia , Aspergillus , Rhizopus , Staphylococcus aureus , Extratos Vegetais/farmacologia , Testes de Sensibilidade Microbiana , Metanol , Escherichia coli , Antibacterianos/farmacologia
3.
Braz. j. biol ; 83: e249536, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1345531

RESUMO

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.


Assuntos
Sargassum , Arábia Saudita , Extratos Vegetais , Oceano Índico , Antibacterianos/farmacologia
4.
Braz. j. biol ; 83: e247016, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339416

RESUMO

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.


Assuntos
Animais , Oligoquetos , Staphylococcus aureus , Testes de Sensibilidade Microbiana , Ampicilina/farmacologia , Antibacterianos/farmacologia
5.
Braz. j. biol ; 83: e245585, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339413

RESUMO

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.


Assuntos
Humanos , Staphylococcus aureus , Resíduos Industriais , RNA Ribossômico 16S , Extratos Vegetais , Testes de Sensibilidade Microbiana , Escherichia coli , Cromatografia Gasosa-Espectrometria de Massas , Antibacterianos/farmacologia
6.
Braz. j. biol ; 83: e236649, 2023. tab
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339379

RESUMO

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.


Assuntos
Euphorbiaceae , Croton , Extratos Vegetais/farmacologia , Compostos Fitoquímicos , Antibacterianos/farmacologia , Antioxidantes/farmacologia
7.
Braz. j. biol ; 83: e248063, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1339340

RESUMO

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.


Assuntos
Lauraceae , Persea , Extratos Vegetais/farmacologia , Frutas , Bactérias Gram-Negativas , Bactérias Gram-Positivas , Antibacterianos/farmacologia
8.
Braz. j. biol ; 83: e244479, 2023. tab, graf
Artigo em Inglês | MEDLINE, LILACS, VETINDEX | ID: biblio-1285635

RESUMO

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.


Assuntos
Árvores , Folhas de Planta , Arábia Saudita , Extratos Vegetais/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier , Antibacterianos/farmacologia
9.
Dermatol Ther ; 35(2): e15222, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34820982

RESUMO

Atmospheric-pressure, non-thermal plasma destroys microorganisms by directly reacting with hydrocarbon molecules in the cell wall and/or by damaging the cytoplasmic membrane, proteins, and DNA with charged particles and reactive species. The aim of our study was to evaluate the antibacterial and anticandidal effects of atmospheric-pressure, non-thermal, nitrogen- and argon-plasma pulses on various pathogen preparations. The resultant antibacterial and anticandidal effects were assessed by evaluating percent and log reduction values for pathogen colonies. Nitrogen-plasma pulses emitted at an energy of 1.5 J and argon-plasma pulses generated at 0.5 J elicited remarkable antibacterial effects on Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, Staphylococcus aureus, and methicillin-resistant Staphylococcus aureus (MRSA) and anticandidal effects on Candida albicans. Nitrogen-plasma pulses at a pulse count of five elicited remarkable antibacterial effects on Cutibacterium acnes at the energy settings of 1.75, 2.5, and 3 J, but not at 1 J. Meanwhile, argon-plasma pulses showed antibacterial effects on C. acnes at an energy of 0.5 and 0.65 J. Nitrogen- or argon-plasma pulses exert antibacterial and anticandidal effects on bacterial and fungal pathogens.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Antibacterianos/farmacologia , Argônio/farmacologia , Pressão Atmosférica , Humanos , Nitrogênio/farmacologia , Pseudomonas aeruginosa
10.
Artigo em Inglês | MEDLINE | ID: mdl-35682504

RESUMO

PURPOSE: Due to the lack of systematic data on antibiotic sensitivity, the treatment of the highly prevalent and pathogenic Helicobacter pylori (H. pylori) infection still poses a significant problem. Therefore, the aim of our study was to compare the efficacy of the three most commonly used anti-H. pylori therapies in northeastern Poland. PATIENTS AND METHODS: This was a retrospective, single-center study performed on 289 outpatients with an H. pylori infection. Patients received one of the following three treatment regimens: (1) bismuth quadruple therapy (BQT) for 10 days, (2) metronidazole-based triple therapy (M-TT) for 10 or 14 days, and (3) levofloxacin-based triple therapy (L-TT) for 10 or 14 days. RESULTS: BQT, M-TT, and L-TT accounted for 93.2% of prescribed anti-H. pylori therapies. The overall success rate for all treatment regimens was 84.1% (243/289). The effectiveness of first- and second-line therapy was similar and reached 83.8% and 86.2%, respectively. The efficacy of the individual treatment regimens was as follows: (1) BQT-89.4% (84/94), (2) M-TT-80.6% (112/139) and 78.8% (26/33) for 10 and 14 days, respectively, and (3) L-TT-84.6% (11/13) and 100% (10/10) for 10 and 14 days, respectively. The overall duration of treatment and type and dose of proton pump inhibitor (PPI) had no effect on the treatment efficacy. CONCLUSIONS: In the northeastern part of Poland, 10-day BQT and 10- or 14-day L-TT are effective treatment regimens for H. pylori eradication and have appear to be superior to M-TT. Practitioners in our clinic followed mostly local anti-H. pylori therapy guidelines.


Assuntos
Infecções por Helicobacter , Helicobacter pylori , Antibacterianos/farmacologia , Bismuto/uso terapêutico , Quimioterapia Combinada , Infecções por Helicobacter/tratamento farmacológico , Infecções por Helicobacter/epidemiologia , Infecções por Helicobacter/etiologia , Humanos , Metronidazol/uso terapêutico , Polônia/epidemiologia , Inibidores da Bomba de Prótons/uso terapêutico , Estudos Retrospectivos
11.
Environ Pollut ; 307: 119603, 2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35691443

RESUMO

Mutations are an important origin of antibiotic resistance in bacteria. While there is increasing evidence showing promoted resistance mutations by environmental stresses, no retrospective research has yet been conducted on this phenomenon and its mechanisms. Herein, we summarized the phenomena of stress-elevated resistance mutations in bacteria, generalized the regulatory mechanisms and discussed the environmental and human health implications. It is shown that both chemical pollutants, such as antibiotics and other pharmaceuticals, biocides, metals, nanoparticles and disinfection byproducts, and non-chemical stressors, such as ultraviolet radiation, electrical stimulation and starvation, are capable of elevating resistance mutations in bacteria. Notably, resistance mutations are more likely to occur under sublethal or subinhibitory levels of these stresses, suggesting a considerable environmental concern. Further, mechanisms for stress-induced mutations are summarized in several points, namely oxidative stress, SOS response, DNA replication and repair systems, RpoS regulon and biofilm formation, all of which are readily provoked by common environmental stresses. Given bacteria in the environment are confronted with a variety of unfavorable conditions, we propose that the stress-elevated resistance mutations are a universal phenomenon in the environment and represent a nonnegligible risk factor for ecosystems and human health. The present review identifies a need for taking into account the pollutants' ability to elevate resistance mutations when assessing their environmental and human health risks and highlights the necessity of including resistance mutations as a target to prevent antibiotic resistance evolution.


Assuntos
Poluentes Ambientais , Raios Ultravioleta , Antibacterianos/farmacologia , Bactérias/genética , Ecossistema , Poluentes Ambientais/toxicidade , Mutação
12.
J Environ Manage ; 317: 115362, 2022 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-35642820

RESUMO

Sewage treatment plants are an essential source of antibiotics, antibiotic resistance determinants, and bacteria in environmental waters. However, it is still unclear whether they can maintain a relatively stable relationship in wastewater and environmental waters. This study analyzed the removal capacity of the above three pollutants in the sewage treatment plant in summer and their impact on environmental waters, and then examines the relationship between the three contaminants in the wastewater and environmental waters in summer and winter based on our previous study. The results found that the removal capacity of bacteria in summer was poor, the concentration of fluoroquinolone in the effluent was higher than that in influent, and the abundance of intI1, tetW, qnrB, and ermB increased after wastewater treatment. Proteobacteria and Bacteroides were the main bacteria that constitute the correlation network between bacteria, and they existed stably in summer and winter. However, fluoroquinolones occupied a significant position in the determinant network of antibiotics and antibiotic resistance in summer and winter. There are fewer correlation between antibiotics and antibiotics resistance determinants in winter. Interestingly, the relationship between bacteria, antibiotics, and antibiotic resistance determinants was a mainly positive correlation in summer and negative correlation in winter. This study analyzed the relationship between bacteria, antibiotics, and antibiotic resistance determinants that were stable in the wastewater and environmental waters and pointed out the direction for subsequent targeted seasonal control of novel pollutants in wastewater and environmental waters.


Assuntos
Poluentes Químicos da Água , Purificação da Água , Antibacterianos/análise , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos , Genes Bacterianos , Estações do Ano , Esgotos/microbiologia , Águas Residuárias/análise , Água , Poluentes Químicos da Água/análise , Purificação da Água/métodos
13.
Sci Total Environ ; 838(Pt 3): 156263, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35644396

RESUMO

Municipal sewage sludge, a reservoir of antibiotic resistance genes (ARGs), is usually composted as fertilizer for agricultural application especially in arid and semi-arid areas. The evolution patterns of intracellular ARGs (iARGs) and extracellular ARGs (eARGs) during composting and their responses to soil salinization after long-term compost application kept unclear previously, which were systematically studied in the current study. The variation and dissemination risk of eARGs and iARGs with the salinization of farmland soils was also evaluated. Extra/intra-cellular ARGs relative abundance varied drastically through composting process. Generally, the relative abundance of the cell-free eARGs (f-eARGs) and the cell-adsorbed eARGs (a-eARGs) were 4.62 and 3.54 folds (median) higher than that of iARGs, respectively, during the entire composting process, which held true even before the sludge composting (false discovery rate, FDR p < 0.05). There was no significant difference in relative abundance between f-eARGs and a-eARGs. The relative abundance of eARGs gradually decreased with composting time but was relatively higher than iARGs. It was worth noting that iARGs rebounded in the maturation phase. However, an over ten-year application of the eARG-rich compost led to much more severe contamination of iARGs than eARGs in soil. Soil salinization caused remarkable rise of eARGs by 943.34-fold (FDR p < 0.05). The variation of ARGs during composting and soil salinization was closely related to the change of microbial community structure. In compost, the bacterial communities mainly interacting with ARGs were the Firmicutes (54 unique and 35 shared core genera); and the bacterial communities playing major roles in ARGs during soil salinization were Proteobacteria (116 unique and 53 shared core genera) and Actinobacteria (52 unique and 27 shared core genera). These findings are important for assessing the transmission risk of ARGs in compost application to farmland in arid and semi-arid areas.


Assuntos
Compostagem , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Esterco/microbiologia , Esgotos/microbiologia , Solo/química
14.
Sci Total Environ ; 838(Pt 3): 156470, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35660582

RESUMO

Microplastics (MPs) provide attachment sites for biofilm formation of microorganisms, which can promote their resistance to environmental stress has been proved. However, the effect of MPs on synergy survival among microorganisms under antibiotic stress remains unclear. In the present study, the proliferation of Escherichia coli and Pseudomonas aeruginosa was assessed under enrofloxacin stress with the influence of MPs. Here, MPs reduced the growth speed of E. coli and enhanced that of P. aeruginosa, especially at 12 h, but the final value of OD600 and CFU of both bacteria not be influenced. E. coli was enrofloxacin sensitive (MIC = 0.25 µg/mL), and a high MP concentration in the presence of enrofloxacin notably enhanced the biofilm formation ability of P. aeruginosa, but proliferation decreased. In the coculture system, the proliferation of E. coli (increased 1.42-fold) and P. aeruginosa (increased 1.06-fold) both increased under enrofloxacin stress (0.25 µg/mL) with high-concentration MP addition. P. aeruginosa may provide the biofilm matrix for E. coli to resist the stress of enrofloxacin. The high concentration of cyclic AMP secreted by E. coli may slightly inhibited biofilm formation, leading to a decrease in the fitness cost of P. aeruginosa; thus, the proliferation of P. aeruginosa increased. The present study is the first to show that MP combined with antibiotics stimulates the metabolic cooperation of bacteria to promote proliferation.


Assuntos
Escherichia coli , Pseudomonas aeruginosa , Antibacterianos/farmacologia , Bactérias , Biofilmes , Proliferação de Células , AMP Cíclico/farmacologia , Enrofloxacina , Testes de Sensibilidade Microbiana , Microplásticos , Plásticos
15.
Sci Total Environ ; 838(Pt 3): 156443, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35660621

RESUMO

Antimicrobial resistance (AMR) in the environment has attracted increasing attention as an emerging global threat to public health. Stone is an essential ecosystem in nature and also an important material for human society, having architectural and aesthetic values. However, little is known about the AMR in stone ecosystems, particularly in the stone monument, where antimicrobials are often applied against biodeterioration. Here, we provide the first detailed metagenomic study of AMR genes across different types of biodeteriorated stone monuments, which revealed abundant and diverse AMR genes conferring resistance to drugs (antibiotics), biocides, and metals. Totally, 132 AMR subtypes belonging to 27 AMR types were detected including copper-, rifampin-, and aminocoumarins-resistance genes, of which diversity was mainly explained by the spatial turnover (replacement of genes between samples) rather than nestedness (loss of nested genes between samples). Source track analysis confirms that stone resistomes are likely driven by anthropogenic activities across stone heritage areas. We also detected various mobile genetic elements (namely mobilome, e.g., prophages, plasmids, and insertion sequences) that could accelerate replication and horizontal transfer of AMR genes. Host-tracking analysis further identified multiple biodeterioration-related bacterial genera such as Pseudonocardia, Sphingmonas, and Streptomyces as the major hosts of resistome. Taken together, these findings highlight that stone microbiota is one of the natural reservoirs of antimicrobial-resistant hazards, and the diverse resistome and mobilome carried by active biodeteriogens may improve their adaptation on stone and even deactivate the antimicrobials applied against biodeterioration. This enhanced knowledge may also provide novel and specific avenues for environmental management and stone heritage protection.


Assuntos
Antibacterianos , Microbiota , Antibacterianos/farmacologia , Bactérias , Farmacorresistência Bacteriana/genética , Genes Bacterianos , Humanos , Metagenômica
16.
J Mater Chem B ; 10(24): 4640-4649, 2022 Jun 22.
Artigo em Inglês | MEDLINE | ID: mdl-35666216

RESUMO

Calcium silicate-based cement (CSC) has attracted much interest because of its favourable osteogenic effect that supports its clinical use. Although CSC has antibacterial activity, this activity still needs to be improved when used in an infected bone defect. Natural polyphenols have been considered antimicrobial reagents. To this end, three different types of polyphenols (gallic acid (GA), pyrogallol (PG) and tannic acid (TA)) with different concentrations as a liquid phase were mixed with bioactive calcium silicate to enhance the antibacterial activity of CSC. The setting time, antibacterial activity, and osteogenic activity of CSC were studied. Evaluation of antibacterial ability and reactive oxygen species (ROS) was performed using Gram-negative Escherichia coli (E. coli) and Gram-positive Staphylococcus aureus (S. aureus) bacteria, while a human osteoblast-like cell line (MG63) was used to examine osteogenic activity. The experimental results showed that the addition of polyphenols did not remarkably affect the phase composition and morphology of CSC, but changed the setting time and diametral tensile strength. At the same concentration of 1 wt%, the setting time of TA (21 min) was significantly shorter than that of PG (26 min) and GA (68 min), and was indistinguishable from the control cement (20 min). GA had a significantly higher antioxidant activity than PG and TA. As expected, higher concentrations of polyphenols had a more positive impact on ROS generation. More importantly, the incorporation of polyphenols greatly enhanced the antibacterial activity of CSC against E. coli and S. aureus, but had little effect on the in vitro osteogenic activity of MG63 cells and the cytotoxicity of L929 cells. It was concluded that among the three phenolic compounds, the optimal concentration of the liquid phase in the hybrid cement was 5 wt% TA in terms of setting time, strength, antibacterial activity and in vitro osteogenic activity.


Assuntos
Cimentos Ósseos , Infecções Estafilocócicas , Antibacterianos/farmacologia , Compostos de Cálcio , Escherichia coli , Humanos , Polifenóis/farmacologia , Espécies Reativas de Oxigênio , Cimento de Silicato , Silicatos , Staphylococcus aureus
17.
Food Chem ; 393: 133370, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-35667177

RESUMO

The Thymus plants have been used for centuries in traditional medicine and as a food spice, among this genus, Thymus zygis (red thyme) is a widespread plant, vastly used as a culinary flavouring agent. Its essential oil has demonstrated diverse bioactive properties, such as antimicrobial, insecticidal, larvicidal and antiparasitic activities. Numerous studies have characterized this essential oil showing that it possesses a broad antimicrobial spectrum and may even enhance the effect of certain antimicrobial agents. Its potential application as a food preservative has been analysed on different matrixes pointing to its antimicrobial activity against spoilage and pathogenic microorganisms in food. This review provides an insight in the chemical composition, antimicrobial, insecticidal, larvicidal and antiparasitic activities and toxicity of T. zygis essential oil, as well as its potential application in food as a preservative.


Assuntos
Anti-Infecciosos , Lamiaceae , Óleos Voláteis , Thymus (Planta) , Antibacterianos/química , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Antiparasitários , Lamiaceae/química , Óleos Voláteis/química , Óleos Voláteis/farmacologia , Thymus (Planta)/química
18.
Sci Total Environ ; 838(Pt 3): 156536, 2022 Sep 10.
Artigo em Inglês | MEDLINE | ID: mdl-35679927

RESUMO

Urban rivers dynamically interfered by anthropogenic activities are considered as a vital reservoir of antibiotic resistance genes (ARGs). Here, a total of 198 ARGs and 12 mobile genetic elements (MGEs) were profiled in water and sediment from the Chaobai river, Beijing. The total abundances of ARGs (1.01 × 106-4.58 × 108 copies/L in water and 2.92 × 106-3.34 × 109 copies/g in sediment), which were dominated by beta-lactamase genes, exhibited significant seasonal variations (p < 0.05). Significant linear correlations between the total abundances of ARGs and MGEs were observed in both water and sediment (p < 0.01). Variance partitioning analysis disclosed that environmental variables (i.e., water temperature (WT), dissolved oxygen (DO), nutrients, metals, etc.) and antibiotics were the main contributors to the variations of ARGs and MGEs, and explained 55-80 % and 27-67 % of the total variations in ARGs and MGEs, respectively. The partial least-squares path model revealed the ARG abundances in water and sediment were affected by environmental variables and antibiotics both directly and indirectly but by MGEs directly. Moreover, random forest algorithm explored that WT, Ni, DO, Co, and polyether and macrolide antibiotics were the main drivers (>10 %) of ARGs dissemination in water, whereas the transposase genes of Tp614, tnpA, and IS613 were the main drivers of ARGs dissemination in both water and sediment. This study provides a comprehensive understanding of the driving factors for the ARGs dissemination in an urban river, which is of great significance for risk management of antibiotic resistome.


Assuntos
Antibacterianos , Rios , Antibacterianos/farmacologia , China , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Água
19.
ACS Appl Bio Mater ; 5(6): 3115-3125, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35642387

RESUMO

In this work, ultrasmall gold nanoclusters (AuNCs) have been in situ synthesized in nanopores of covalent organic framework (COF) nanoparticles, which exhibited enhanced fluorescence, improved photosensitizing capabilities, and promising antibacterial performance. A small organic molecule, 1-vinylimidazole (Vim), was diffused into the nanopores of imine-based COFs and served as a reducing agent and capping ligand for the in situ synthesis of ultrasmall AuNCs. The as-obtained AuNCs were homogeneously distributed throughout the COF nanoparticles whose fluorescence intensity was enhanced remarkably. Due to the efficient electron transfer between AuNCs and COFs and increased separation of photogenerated electron-hole pairs, the light-triggered reactive oxygen species (ROS) production of COFs was prominently enhanced by AuNCs. Moreover, the obtained nanocomposites exhibited an efficient photodynamic killing behavior on Escherichia coli under visible light exposure. Thus, we provide a facile strategy to prepare COF/AuNC nanocomposites for ROS-related applications.


Assuntos
Nanopartículas Metálicas , Estruturas Metalorgânicas , Antibacterianos/farmacologia , Ouro/farmacologia , Estruturas Metalorgânicas/farmacologia , Espécies Reativas de Oxigênio
20.
Inorg Chem ; 61(24): 9328-9338, 2022 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-35666261

RESUMO

Two-dimensional (2D) metal-organic framework (MOF) nanosheets have been demonstrated to be promising templates for the growth of various kinds of nanomaterials on their surfaces to construct novel 2D composites, thus realizing enhanced performance in various applications. Herein, we report the growth of Cu2O nanoparticles on 2D Zr-ferrocene (Zr-Fc)-MOF (Zr-Fc-MOF) nanosheets to prepare 2D composites for near-infrared (NIR) photothermally enhanced chemodynamic antibacterial therapy. The uniform Zr-Fc-MOF nanosheets are synthesized using the solvothermal method, followed by ultrasound sonication, and Cu2O nanoparticles are then deposited on its surface to obtain the Cu2O-decorated Zr-Fc-MOF (denoted as Cu2O/Zr-Fc-MOF) 2D composite. Promisingly, the Cu2O/Zr-Fc-MOF composite shows higher chemodynamic activity for producing ·OH via Fenton-like reaction than that of the pristine Zr-Fc-MOF nanosheets. More importantly, the chemodynamic activity of the Cu2O/Zr-Fc-MOF composite can be further enhanced by the photothermal effect though NIR laser (808 nm) irradiation. Thus, the Cu2O/Zr-Fc-MOF composite can be used as an efficient nanoagent for photothermally enhanced chemodynamic antibacterial therapy.


Assuntos
Estruturas Metalorgânicas , Nanopartículas , Nanoestruturas , Antibacterianos/farmacologia , Estruturas Metalorgânicas/farmacologia , Metalocenos/farmacologia
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