FIG. 1.

Changes in viable cell numbers (A) and intracellular levels of ROS (B) of strain BY4741 after freeze-thaw treatment. In panel A, viable cell numbers were measured after freeze-thaw treatment for 24 to 96 h. In panel B, the intracellular levels of ROS were measured after postthaw incubation preceded by freeze-thaw treatment for 24 to 96 h. The fluorescence intensity of the cells before freeze-thaw treatment was relatively set as 100%. The values are the means and standard deviations of results from three independent experiments.