Fig. 2
Representative images of bacteria colonies grown on BHI agar showing antibacterial effect of Zn2+ (Zn(NO3)2·6H2O) against planktonic E. faecalis. A blank control group (BLK); B–F E. faecalis incubated with different concentrations of Zn(NO3)2·6H2O (final concentration, in mg/mL, from B to F 2.8 × 10−2, 8.4 × 10−2, 16.8 × 10−2, 25.2 × 10−2, 33.6 × 10−2). G Comparisons of bacterial CFUs count among groups