Fig. 2
Antibacterial effects of different ZVI NP concentrations against E. coli and Bacillus strains. a B. subtilis 3610 (Bs 3610), B. thuringiensis 407 (Bt 407), E. coli K12 (Ec K12), and E. coli ATCC11634 (Ec ATCC11634) grown in MHB medium were treated with different concentrations of ZVI NPs at 37 °C with shaking at 175 rpm for 3 h; antibacterial activity was evaluated by plating and counting cells. B. subtilis 3610, B. thuringiensis 407, E. coli K12, and E. coli ATCC11634 grown in MHB medium were treated with different concentrations of b Fe2O3 c Oxidized Fe(ZVI) NPs at 37 °C with shaking at 175 rpm for 3 h; antibacterial activity was evaluated as above. Data are expressed as means ± standard deviations of two separate experiments, with three replicates. **p < 0.01 as determined by ANOVA relative to the control sample at different pH values