FIG. 4.

Optimization of the amplification time of phages. The crossover point of E. coli ER2738 growth curve and the survival rate of HCT-8 cells in LB broth was chosen to be the optimal time for phage amplification using E. coli ER2738, and the optimal amplification time of phages was measured to be 5 h. Note that three consecutive experiments were performed and the error was less than 2%. (100% E. coli represents the highest cell number after 8-h culture. Percentage of E. coli were defined as the cell number at a specific time divided by the highest cell number.)