FIG. 6.
Effects of pH on the rate of inactivation of M. gordonae. Experimental conditions were a temperature of 25°C and an initial chlorine concentration of 0.5 mg/liter. Cells were grown in Middlebrook 7H9-Tween medium. No, initial number of CFU; N, number of CFU at each time point. Experiments were conducted with different phosphate (0.05 M) buffers within the pH range of 6.0 to 8.0. Slopes were calculated as follows: pH 6, y = 0.11 x; pH 7, y = 0.09 x; and pH 8, y = 0.02 x. R2 , correlation coefficient values.