| Congresso Brasileiro de Microbiologia 2023 | Resumo: 76-1 | ||||
Resumo:Microbial resistance is one of the biggest problems faced by the health area, due to frequent mutations of microorganisms and the inappropriate use of antibiotics. In this sense, the use of medicinal plants with antimicrobial potential ends up being an alternative treatment, as is the case of Cymbopogon citratus (Capim Santo). To verify the antimicrobial properties of the plant, the essential oil (EO) of the Capim Santo was extracted, whose composition has limonene, citronellal, myrcene, geraniol, and citral. The EO was tested against the bacteria Escherichia coli and Staphylococcus aureus. Initially, the Kirby-Bauer test was performed, with positive controls (Chloramphenicol and Meropenem, for S.aureus and E.coli, respectively), negative control (disc without active), blank (disc with tween 80) and the test discs in triplicate, sensitized with 10μl of the essential oil, seeded onto Mueller Hinton Agar plate. Then, the Minimum Inhibitory Concentration (MIC) test was performed in triplicate on ELISA microplate with initial concentration of 550 mg/ml of the EO, which was diluted to 275 mg/ml up to 1.07 mg/ml. The initial Kirby-Bauer result demonstrated a zone of inhibition greater than 14 mm against S.aureus, demonstrating high sensitivity of the bacteria to the components of the EO, but a smaller zone of inhibition for E.coli, indicating lower sensitivity. Then, the MIC result, for S.aureus demonstrated that there was no bacterial growth in any of the dilutions, resulting in an MIC with a concentration of 1.07 mg/ml, while for E.coli bacterial growth was observed starting at concentration 68.75 mg/ml, causing an MIC with a concentration of 137.5 mg/ml. Thus, it can be inferred that Capim Santo has a superior efficacy on Gram positive bacteria, when compared to its action on Gram negative bacteria, since, the results, both of the diffusion disc and the MIC, demonstrated that lower dilutions are effective in inhibiting the growth of S.aureus (Gram positive), while this is not evident in E.coli (Gram negative). These are preliminary results that allow us to affirm the pharmacological potential of Cymbopogon citratus and its molecules that may aid in fighting infections by resistant and pathogenic bacterial strains. Palavras-chave: Essential oil, antimicrobial activity, medicinal plants. Agência de fomento:PROPESP/UFPA EDITAL PAEPE 14/2020 | |||||