| Congresso Brasileiro de Microbiologia 2023 | Resumo: 803-1 | ||||
Resumo:Bacteria of the genus Staphylococcus stand out due to their pathogenicity and ability to persist in the environment. Biofilm formation becomes one of the main defense mechanisms of this pathogen against antimicrobials. In this perspective, alternative therapies are being developed to enhance the biological activity of natural substances capable of inhibiting and/or disrupting biofilm formation. However, studies evaluating the action of substances on different intensities of biofilm formation in Staphylococcus aureus are scarce. Therefore, the objective of this study was to evaluate the antibiofilm activity of the crude extract of Hymenaea martiana leaves (EEB), gallic acid, and p-coumaric acid, as well as their ability to destabilize preformed biofilms. The EEB was obtained through exhaustive maceration with 95% ethanol (Labsynth, Diadema, Brazil), and its chemical constituents were obtained commercially from Sigma-Aldrich® (USA). Six clinical isolates were used, provided by the Laboratory of Microbiology and Immunology, Federal University of Vale do São Francisco, and strains from the American Type Culture Collection, ATCC 25923 and 33591 of S. aureus. All isolates were capable of producing biofilms to varying degrees. The crystal violet assay was used to investigate the biofilm inhibition effect. The minimum inhibitory concentration for EEB was (390.62 μg/ml), for p-coumaric acid (2,048.0 µg/mL), and for gallic acid (32 µg/mL), except for isolate six, which was 64 µg/mL. After exposure to the tested substances, p-coumaric acid at ½ and ¼ of the MIC showed better antibiofilm activity than gallic acid and H. martiana EEB against all other isolates, with statistically significant reduction, altering their biofilm production from strong to moderate or non-forming. The effect of degrading biofilms adhered to stainless steel structures was observed by evaluating exopolysaccharide production and bacterial auto-aggregation through scanning electron microscopy. Significant changes in EPS production and bacterial aggregation were observed in S. aureus in the presence of p-coumaric acid at ½ of the MIC. The biofilm formation dynamics were altered due to the ability of p-coumaric acid to reduce extracellular polysaccharide, protein, and DNA proliferation.These results suggest that p-coumaric acid may be a potential alternative therapeutic agent to interfere with biofilm formation in early stages or disrupt established biofilms in S. aureus. Palavras-chave: Biofilm, Natural Extract, Secondary Metabolites, Antimicrobial Resistance, P-coumaric acid Agência de fomento:Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) | |||||