Tolerance of Chemoorganotrophic Bioleaching Microorganisms to Heavy Metal and Alkaline Stresses

Figure 3

Growth curves of Bacillus mucilaginosus in broth in the presence of 100 ppm Cd(II) (0.9 mM), As(III) (1.3 mM), or Ni(II) (1.7 mM) compared to a blank medium without metal addition, determined according to optical density: (1) lag phase, (2) exponential phase, and (3) stationary phase.