Estudo da ação antimicrobiana de Ga(NO3)3 em cepas bacterianas

Abstract

According to the World Health Organization in 2020, from all hospitalized patients, a share of cases are infections acquired in a hospital environment due to invasive procedures. For decades, Escherichia coli and Staphylococcus aureus strains have been reported as the main cause of hospital infections. In this way, these microorganisms have developed resistance to various medications over time, reducing the diversity of means to contain their action, highlighting the importance of developing new alternatives with antimicrobial properties. Thus, the use of gallium (Ga3+), which causes harmful effects to bacterial activities due to its characteristics and physicochemical properties similar to those of iron (Fe3+), leads to the possibility to regulate the growth of both planktonic forms and biofilms. Therefore, due to the antimicrobial potential of Ga3+ compounds, this work has performed serial microdilution tests in order to identify the minimum inhibitory concentration (MIC) capable of reducing the growth of representative strains of E. coli and S. aureus. It was possible to verify a reduction in the growth of these microorganisms at 11.25 μM and 1.40 μM of gallium nitrate (Ga(NO3)3), respectively. Thus, the concentrations obtained in this work were able to reduce 50% of the growth of tested microorganisms. This result showed that minor concentrations of Ga(NO3)3 were sufficient against nosocomial pathogens cultures when compared to the literature data.