Figure 3
Intracellular folate levels (open bars) and the corresponding redox ratio (closed bars) measured after 6 h in the control culture C, culture H treated with H2O2, culture H + A treated with H2O2 followed by the antioxidant mannitol and culture M treated with menadione. Oxidative stress induction led to significant decreases in both folate and the redox ratio. Culture C refers to control. Oxidative stress was induced in the bacterial cultures with pulses of H2O2 (H and H + A) and menadione (M), after 5.5 h. Values are expressed as mean ± SD, n = 3. One way ANOVA of the intracellular folate levels and the redox ratio showed that differences in the values of the different cultures were significant with p < 0.001 for intracellular folate and p = 0.002 for redox ratio. Tukey’s multiple comparisons test showed that redox ratio levels in H + A and M and folate levels in all the cultures were significantly different from control.
