*2.6. Effect of POE on Tert-Butyl Hydroperoxide-Induced Oxidative Stress*

To further verify the potential antioxidant role of POE against intracellular ROS formation, the effect of POE was also investigated in Caco-2 cells acutely treated with the pro-oxidant agent tert-butyl hydroperoxide (TBHP).

As shown in Figure 8, TBHP induced a more than three-fold increase in intracellular ROS production with respect to control cells (*p* < 0.001). NAC was able to reduce intracellular ROS production in TBHP-treated cells (*p* < 0.001). POE showed a comparable effect to NAC in TBHP-treated cells (Figure 8).

**Figure 8.** Effect of POE on TBHP-induced ROS formation in Caco-2 cells. Intracellular ROS production was evaluated in Caco-2 cells pre-incubated for 24 h with POE (15 μg GAE/mL) or NAC (50μM) and treated with TBHP (50 μM) for 90 min. Values are represented as the mean ± SD of five determinations carried out in triplicate. \*\*\* Control vs. TBHP; \*\*\* NAC + THBP vs. TBHP; \*\* POE + THBP vs. TBHP (ANOVA: \*\*: *p* < 0.01; \*\*\*: *p* < 0.001).
