Effects of photoactivated Lonicera japonica on reactive oxygen species (ROS) production in CH27 cells. Cells were loaded with 5-H2DCFDA (5 μM) for 30 min in the dark, washed and then treated with 0.1% DMSO or with 50, 75 or 100 μg/ml Lonicera japonica for 2 h and then irradiated with 0.8 J/cm2 fluence dose. After irradiation, ROS fluorescence was measured using a multiwell plate reader at an excitation wavelength of 485 nm and an emission wavelength of 538 nm. All results are expressed as the mean percentage of control ± S.D. of triplicate determinations from four independent experiments. **
P < 0.01, ***
P < 0.001 compared to the corresponding control values.