A synergistic anti-bacterial and anti-adhesion activity of tea tree (Melaleuca alternifolia) and lemon eucalyptus tree (Eucalyptus citriodora Hook) essential oils on Legionella pneumophilaOder, Martina (Avtor) Piletić, Kaća (Avtor) Fink, Rok (Avtor) Marijanović, Zvonimir (Avtor) Krištof, Romana (Avtor) Bićanić, Lucija (Avtor) Tomić Linšak, Dijana (Avtor) Gobin, Ivana (Avtor) anti-Legionella activityanti-adhesionmass spectrometryessential oilscheckerboard assayLegionella pneumophila is a Gram-negative bacterial pathogen that colonizes natural and artificial water systems and has the ability to form a biofilm. The biofilm protects L. pneumophila from various environmental factors and makes it more resistant to chlorine-based disinfectants. This study investigated the anti-bacterial properties of tea tree (Melaleuca alternifolia (Maiden and Betche) Cheel) oil and lemon eucalyptus tree (Eucalyptus citriodora Hook) essential oils (EOs) and their synergistic, additive inhibitory and anti-adhesive effects against L. pneumophila biofilm formation on polystyrene. The minimum effective concentration (MEC) for tea tree is 12.8 mg ml$^{−1}$ and for lemon eucalyptus tree EO 6.4 mg ml$^{−1}$. In the checkerboard assay, different combinations of these two EO show synergistic and additive anti-microbial activity. The minimum anti-adhesive concentration (MAC) for tea tree is 12.8 mg ml$^{−1}$ and for lemon eucalyptus tree EO 6.4 mg ml$^{−1}$. A combination of 3.2 mg ml$^{−1}$ tea tree EO and 0.8 mg ml$^{−1}$ lemon eucalyptus tree EO showed the strongest anti-adhesive effect against L. pneumophila on polystyrene. The tested oils and their combination showed intriguing potential to inhibit L. pneumophila biofilm formation.20242024-03-11 14:08:57Članek v reviji154949sl