Chemical composition and antibacterial activity of essential oils from Cymbopogon winterianus (citronella), Eucalyptus paniculata (eucalyptus) and Lavandula angustifolia (lavender) ; Composição química e atividade antibacteriana dos óleos essenciais de Cymbopogon winterianus (citronela), Eucalyptus paniculata (eucalipto) e Lavandula angustifolia (lavanda)

The chemical composition of essential oils derived from three medicinal plant species growing in the South of Brazil: Cymbopogon winterianus (citronella), Eucalyptus paniculata (eucalyptus), and Lavandula angustifolia (lavender) was determined, and their antimicrobial activities were evaluated against 11 bacterial species, including those related to foodborne and human pathogens. The essential oils were obtained by steam distillation, and its chemical composition was analyzed by GC and GC/MS. Antimicrobial activity was screened by disc-diffusion assay. MIC and MBC of the sensitive strains were determined by microdilution methodology. The main components of lavender and citronella essential oils were the oxygenated monoterpenes, and the monoterpene hydrocarbons in eucalyptus oil. Citronella oil showed the lowest MIC and MBC values on the majority of the tested bacteria, and the MIC and MBC values against Yersinia enterocolitica were of 0.075 and 0.31 mg/mL, respectively. The lavender oil was active against Escherichia coli and Salmonella Typhimurium, and the eucalyptus inhibited the growth of Pseudomonas aeruginosa. This study showed that the evaluated essential oils might be potentially used as natural antimicrobial agents. ; Neste estudo, foi determinada a composição química de óleos essenciais obtidos de três espécies de plantas medicinais cultivadas na região Sul do Brasil: Cymbopogon winterianus (citronela), Eucalyptus paniculata (eucalipto) e Lavandula angustifolia (lavanda), e as atividades antimicrobianas foram avaliadas frente a 11 espécies de bactérias, incluindo-se espécies de importância em alimentos e em saúde pública. A composição dos óleos essenciais, obtidos por destilação a vapor, foi determinada por CG/DIC e CG/EM; a atividade antimicrobiana foi detectada pela técnica de difusão em disco; a CMI e a CMB foram determinadas pela metodologia de microdiluição. Os óleos essenciais de lavanda e citronela apresentaram monoterpenos oxigenados como componentes majoritários e, no óleo essencial de ...