Fig. 6.

Halicin activity against Staphylococcus aureus-Xen 36 biofilms does not depend on DMSO vehicle. Less mature 24-hour biofilms on Ti6Al4V discs were exposed for 20 hours to the indicated concentrations of halicin with either dimethyl sulfoxide (DMSO) (red symbols) or Kolliphor HS 15 (green symbols) as vehicle. Final concentrations of DMSO or Kolliphor HS 15 were 20% in LB broth without kanamycin for groups with halicin at 80 × minimal inhibitory concentration (MIC) and 10% for all other halicin groups. Controls without halicin therefore included groups with 10% or 20% of either DMSO or Kolliphor HS 15 as vehicle. The concentrations of either vehicle did not affect biofilm viability (Supplementary Figure aa). Effects on biofilm viability were determined by colony-forming unit (CFU) assays. Dashed lines connect medians of four independent experiments for each group. Each symbol denotes the median for each group from an independent experiment, with four Ti6Al4V discs per symbol.