Assessment of safe bioactive doses of <i>Foeniculum vulgare</i> Mill. essential oil from Portugal

<p>This study was designed to evaluate the antifungal activity of <i>Foeniculum vulgare</i> essential oil; concomitantly, the safety of bioactive doses was also unveiled, for the first time, in several mammalian cells. The chemical characterisation was made by GC and GC–MS. Antifungal activity was evaluated against yeasts, dermatophytes and <i>Aspergillus</i> strains and germ tube inhibition assay was evaluated using <i>Candida</i> <i>albicans</i>. Cell viability was assessed by the MTT assay. The main constituents of the oil are E-anetol (47%), <i>α</i>-phellandrene (11%), <i>α</i>-pinene (10.1%) and fenchone (10.8%). The oil was more active against <i>Cryptococcus neoformans</i> and <i>C. albicans</i> (MICs 0.32–0.64 μL/mL) and the filamentation of <i>C. albicans</i> was totally inhibited with 0.08 μL/mL. The oil is safe for keratinocytes, hepatocytes and fibroblasts in concentrations up to 1.25 μL/mL, and to macrophages up to 0.64 μL/mL. These findings highlight safe bioactive concentrations that should be deeper investigated for further application in pharmaceutical industry.</p

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