Chemical composition, antimicrobial and antibiofilm efficacy of C. limon and L. angustifolia EOs and of their mixtures against Staphylococcus epidermidis clinical strains

The antibacterial and antibiofilm effects of the EOs and of their mixtures were tested towards five S. epidermidis clinical strains and their biological activity was correlated with the oils composition. The most active composition was represented by the binary mixture (1:1) of the EOs obtained by hydrodistillation, containing terpene alcohols (such linalool) and d-limonene, which exhibited the lowest minimum inhibitory concentration (3.9 μg/mL) and minimum biofilm eradicating concentration (0.97-7.81 μg/mL), against all tested S. epidermidis strains. Other minor constituents, such as terpinen-4-ol, α-terpineol, linalyl acetate, neryl acetate, geranyl acetate and α-pinene could be potentiated in presence of limonene and could be responsible for the high antimicrobial activity of these EOs mixture.