RESUMO
Aim: This work describes the synthesis and antimicrobial evaluation of 6-aminated 1,4-benzoquinones (6-AQs) against seven resistant pathogens.Materials & methods: The 6-AQs, synthesized via a Michael addition reaction between bromoquinone and p-substituted anilines, were assessed for their antimicrobial activity through both in vitro and in silico analyses.Results: Bromoquinone and 6-AQs with electron-withdrawing groups demonstrated activity against Pseudomonas aeruginosa, with minimum inhibitory concentrations ranging from 16 to 128 µg/ml, comparable to standard antimicrobials. Two derivatives exhibited minimum inhibitory concentrations values against methicillin-resistant Staphylococcus aureus ranging from 64 to 128 µg/ml. These compounds demonstrated both bacteriostatic and bactericidal effects, and antibiofilm features.Conclusion: The 6-AQs 19g and 19f showed a promising antimicrobial profile, indicating their potential as new therapeutic options.
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RESUMO
Staphylococcus aureus and Staphylococcus epidermidis are among the most important bacterial species responsible for biofilm formation on indwelling medical devices, including orthopaedic implants. The increasing resistance to antimicrobials, partly attributed to the ability to form biofilms, is a challenge for the development of new antimicrobial agents. In this study, the cell-free supernatant obtained from sponge-associated Enterobacter strain 84.3 culture inhibited biofilm formation (>65%) and dissociated mature biofilm (>85%) formed by S. aureus and S. epidermidis strains. The culture supernatant was subjected to solvent partitioning and the aqueous extract presented a concentration-dependent antibiofilm activity for each strain with a minimum biofilm eradication concentration (MBEC) ranging from 16 to 256 µg/mL. The effect of the aqueous extract on mature S. aureus biofilm was analyzed by confocal scanning laser microscopy, showing a significant reduction of the biofilm layer as well as diminished interactions among the cells. This extract is not toxic for mammalian cells (L929 cell line). Studies targeting substances with antibiofilm activity gained significant attention in recent years due to difficult-to-treat biofilm infections. Here, sponge-associated Enterobacter 84.3 proved to be a source of substances capable of eradicating staphylococcal biofilm, with potential medical use in the future.
Assuntos
Antibacterianos/farmacologia , Biofilmes/crescimento & desenvolvimento , Extratos Celulares/farmacologia , Enterobacter/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus epidermidis/efeitos dos fármacos , Animais , Infecções Relacionadas a Cateter/tratamento farmacológico , Infecções Relacionadas a Cateter/microbiologia , Cateteres de Demora/microbiologia , Linhagem Celular , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/microbiologia , Células L , Camundongos , Testes de Sensibilidade Microbiana , Poríferos/microbiologia , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/prevenção & controleRESUMO
BACKGROUND: Resistance to antimicrobial agents is a major public health problem, being Staphylococcus aureus prevalent in infections in hospital and community environments and, admittedly, related to biofilm formation in biotic and abiotic surfaces. Biofilms form a complex and structured community of microorganisms surrounded by an extracellular matrix adhering to each other and to a surface that gives them even more protection from and resistance against the action of antimicrobial agents, as well as against host defenses. METHODS: Aiming to control and solve these problems, our study sought to evaluate the action of 1,2,3- triazoles against a Staphylococcus aureus isolate in planktonic and in the biofilm form, evaluating the activity of this triazole through Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC) tests. We have also performed cytotoxic evaluation and Scanning Electron Microscopy (SEM) of the biofilms under the treatment of the compound. The 1,2,3-triazole DAN 49 showed bacteriostatic and bactericidal activity (MIC and MBC 128 µg/mL). In addition, its presence interfered with the biofilm formation stage (1/2 MIC, p <0.000001) and demonstrated an effect on young preformed biofilm (2 MICs, p <0.05). RESULTS: Scanning Electron Microscopy images showed a reduction in the cell population and the appearance of deformations on the surface of some bacteria in the biofilm under treatment with the compound. CONCLUSION: Therefore, it was possible to conclude the promising anti-biofilm potential of 1,2,3-triazole, demonstrating the importance of the synthesis of new compounds with biological activity.