Chemical composition and antibacterial activity of <i>Lavandula coronopifolia</i> essential oil against antibiotic-resistant bacteria

<div><p>The aim of this study was to analyse the composition of the essential oil (EO) of <i>Lavandula coronopifolia</i> from Morocco and to evaluate its <i>in vitro</i> antibacterial activity against antibiotic-resistant bacteria isolated from clinical infections. The antimicrobial activity was assessed by a broth micro-well dilution method using multiresistant clinical isolates of 11 pathogenic bacteria: <i>Klebsiella pneumoniae</i> subsp. <i>pneumoniae</i>, <i>Klebsiella ornithinolytica</i>, <i>Escherichia coli</i>, <i>Enterobacter cloacae</i>, <i>Enterobacter aerogenes</i>, <i>Providencia rettgeri</i>, <i>Citrobacter freundii</i>, <i>Hafnia alvei</i>, Salmonella spp., <i>Acinetobacter baumannii</i> and methicillin-resistant <i>Staphylococcus aureus</i>. The main compounds of the oil were carvacrol (48.9%), <i>E</i>-caryophyllene (10.8%) and caryophyllene oxide (7.7%). The oil showed activity against all tested strains with minimal inhibitory concentration (MIC) values ranging between 1% and 4%. For most of the strains, the MIC value was equivalent to the minimal bactericidal concentration value, indicating a clear bactericidal effect of <i>L. coronopifolia</i> EO.</p></div