Figure 4. Combined effects of M17 broth supplemented with 10% (v/v) lactose solution (M17) broth cultured EcN SN and 5-FU (µM) on viability of IEC-6 cells for 24 h (A) or 48 h (B). Cells were treated with DMEM, dried M17 broth re-suspended in DMEM (M17-) to reach final concentrations of 0.0001, 0.01, 1, 100 µg/mL, and 1 mg/mL, or dried EcN SN had grown in M17 broth re-suspended in DMEM (M17⁺) to reach final concentrations of 0.0001, 0.01, 1, 100 µg/mL, and 1 mg/mL, either alone or in combination with 5-FU (1.25 µM). Data are expressed as percentage of viable cells relative to untreated cell controls. Data are presented as means ± SEM of three independent experiments (n = 9). Bar data not sharing the same letter are significantly different (P < 0.05). *Indicates a significant difference compared with 5-FU control in all 5-FU treatment groups (P < 0.05).