Natural antimicrobials on pathogenic bacteria with emphasis on the elaboration of nanoemulsions and gold nanoparticles

Abstract

The indiscriminate use of antibacterial drugs has contributed decisively to the emergence of resistant bacterial strains considered today a widespread public health problem, since the infections caused by these results in an increase in mortality and morbidity in the population. Researches aiming at new therapeutic options that are effective and less susceptible to bacterial resistance such as plant-derived compounds and antimicrobial peptides are promising. Establishing antimicrobial mechanisms of a given product is complex due to the innumerable possibilities of acting in the constitution and bacterial metabolism. Thus, we will use in this project numerous tools to elucidate the antimicrobial activity of natural compounds such as electron microscopy, membrane permeability analysis, enzyme release resulting from cell lysis and proteomic analysis. In this way, we aim to advance the knowledge of the antibacterial action of natural compounds, being these antibacterial peptides (nisin, a bacteriocin, and melittin, a proteic fraction of Apis mellifera apitoxin) and alcoholic extracts of A. mellifera propolis. As a information about this project, we have recently started to focus on the development of nanoemulsions and nanoparticles using natural antibacterial compounds (essential oil of Cymbopogon martinii - palmarosa - and its major compound geraniol) against the anaerobic bacterium Propionibacterium acnes (currently Cutibacterium acnes) with positive results and whose article is in the preparation for its publication. In addition, we intend to use nanoparticles to minimize the cytotoxicity of melitin and to try to potentiate the action of nisin on Gram-negative bacteria. As for the study of propolis, we will carry out tests against sporulated bacteria Paenibacterium alvei, an important pathogen of the A. mellifera, also aiming to increase the use of propolis as an antimicrobial agent. (AU)