Fig. 5. Effect of antibiotic treatments with aqueous solutions on B. subtilis NCIB 3610 biofilms that were cultivated in the presence and absence of metal ions.
Efficiencies (in percentage values) are determined after a treatment of 1 h with either piperacillin/tazobactam, tetracycline, or kanamycin antibiotic solutions, by comparing antibiotic-treated samples vs. those that were exposed to water only (see Methods). The samples consist of biofilm colonies cultivated on LBGM agar with and without (green bars) 1.5 mM CuSO4 (blue bars) or 0.5 mM ZnCl2 (gray bars). Error bars denote the s.d. as determined from at least 8 individual data points, obtained from a minimum of 2 growth batches with 2 biological replicates, and 2 technical replicates each (B ≥ 2, N = 2, n = 2).