| Congresso Brasileiro de Microbiologia 2023 | Resumo: 40-1 | ||||
Resumo:The increasing bacterial resistance to traditional antimicrobials has become a global challenge in the healthcare field. In this context, essential oils from medicinal plants have sparked interest as potential alternative antimicrobial agents.Lippia origanoides is a plant widely used in traditional medicine due to its medicinal properties, including antimicrobial activity. However, studies evaluating the efficacy of the essential oil of L. origanoides (EOLo) and its major constituents against multidrug-resistant clinical isolates of Acinetobacter baumannii and Staphylococcus aureus are scarce. Thus, the objective of this study was to evaluate the antibacterial activity of EOLo and its major constituents against multidrug-resistant clinical isolates of A. baumannii and S. aureus. EOLo was obtained through hydrodistillation, using a Clevenger-type apparatus, and its chemical constituents were commercially obtained from Sigma-Aldrich® (MO, St. Louis, USA). The identification of the major constituents was performed by gas chromatography coupled with mass spectrometry (GC-MS). Nine strains of multidrug-resistant A. baumannii and ten strains of S. aureus were selected from patients admitted to the University Hospital of the Federal University of São Francisco Valley in Petrolina (PE). The identification of bacterial isolates and their susceptibility profile to antimicrobials were determined using the automated PhoenixTM system. The antibacterial activity of the essential oil and its major constituents was evaluated through broth microdilution assay, obtaining the Minimum Inhibitory Concentration (MIC) and Minimum Bactericidal Concentration (MBC). The main constituents identified in the essential oil were the monoterpenes Carvacrol, p-Cymene, and Thymol, present in proportions of 48,44%, 14,58%, and 10,16%, respectively. EOLo, carvacrol, and thymol demonstrated significant antibacterial activity against multidrug-resistant clinical isolates of S. aureus and A. baumannii. The MIC of EOLo ranged from 128 to 256 µg/mL, and the MBC was 256 µg/mL against A. baumannii isolates, while for S. aureus isolates, the MIC ranged from 256 to 512 µg/mL, and the MBC was 512 µg/mL. Regarding the major constituents, carvacrol exhibited higher antibacterial activity, with MIC against A. baumannii ranging from 32 to 64 µg/mL, and MBC ranging from 64 to 128 µg/mL. For S. aureus, the MIC varied from 128 to 256 µg/mL, and the MBC ranged from 128 to 512 µg/mL. This study confirmed that the essential oil of L. origanoides possesses significant antibacterial activity against multidrug-resistant clinical isolates of A. baumannii and S. aureus. Furthermore, the major constituents identified in the essential oil, especially carvacrol, showed promising antibacterial activity. These results suggest that the essential oil of L. origanoides and its constituents could be potential alternative therapeutic agents for the treatment of infections caused by these multidrug-resistant pathogens. Palavras-chave: Phytotherapy, Antimicrobial Resistance, Antibacterial, Infection, Natural Product Agência de fomento:Fundação de Amparo à Ciência e Tecnologia do Estado de Pernambuco (FACEPE), Conselho Nacional de Desenvolvimento Científico e Tecnológico (CNPq) e Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES). | |||||