Figure 4: Effect of D-limonene on H2O2-induced generation of ROS in HLECs. Cells were treated with 100 μM H2O2 for 2 h after incubation in the absence or presence of D-limonene for 24 h. After this treatment, the production of ROS was determined using 10 μM H2DCFDA. The morphological features were observed using fluorescence microscopy.