Minimum Inhibitory Concentration (MIC) to LL-37

MICs were determined by the tube dilution method according to the CLSI. Briefly, the bacterial Müeller-Hinton broth (Becton Dickinson, NJ, USA) cultures were grown overnight at 37 °C, then diluted 1:200 in PBS and adjusted to 0.5 McFarland standard. Later, 20 µL were transferred to tubes containing different concentrations of LL-37 (BAC; Sigma-Aldrich, St. Louis, MO, USA). The tubes were incubated at 37 °C for 18 h and the MIC values were determined (corresponding to the lowest concentration of the compound that inhibited visible growth). Each MIC determination was performed in triplicate, repeated three times.