Fig. 5

Representative images of specimens in sample A groups. Cells were treated with sample A for 3 h in the absence (a, c) or presence (b, d) of S9 mix, followed by recovery culturing for 21 h. The media used in the recovery cultures were as follows: a, b, antibiotic-free medium; c, d, antibiotic-supplemented medium (100 U-µg/mL P/S). The arrowheads indicate the remaining bacteria derived from sample A