Atividade antibacteriana nanoparticulas de ouro e citótoxica de com Epigalocatequina 3-galato (EGCG)

Abstract

Antibiotic resistance is an urgent global health problem. Over time, bacteria have developed defense mechanisms against conventional antibiotics associated with the lack of new drugs that further mitigates the problem. Therefore, it is necessary to develop multi-target, innovative and more effective antibacterial agents to overcome this threat to human health. The present work evaluated the antibacterial activity of reduced and stabilized gold nanoparticles with Epigallocatechin 3-Galate (EGCG). The synthesized nanoparticles (AuNPs-EGCG) were stable under physiological conditions in vitro, as well as resuspension in various solvents. The in vitro antibacterial activity of AuNPs-EGCG was evidenced by a decrease in the number of viable cells and growth inhibition after 12 hours of treatment in both Gram positive and Gram negative bacteria, obtaining minimum inhibitory concentration (MIC) values that varied between 15 and 120 µg.mL-1 in all treated bacteria The bactericidal and bacteriostatic effects of the nanoformulation were generated by the direct interaction with the surfaces of the treated bacteria, thus causing morphological deformations that induced cell lysis and death. In addition, the in vitro cytotoxicity of AuNPs-EGCG in murine fibroblast (L929) and human keratinocytes (HaCaT) showed high levels of cell viability and IC50 values of 267.55 e 293.04 µg.mL-1, respectively after 24 hours of treatment with AuNPs-EGCG. The functionalization of EGCG on the gold core enhanced its antibacterial activity and decreased its in vitro cytotoxicity. AuNPs-EGCG have high potential for future applications in the biomedical field as an antibacterial treatment against skin infections