ROS generation by E. coli O157:H7 and L. monocytogenes cells suspended in PBS after treatment with continuous or pulsed (1,000 Hz/10% or 20 Hz/50%) UVC-LED irradiation

TreatmentROS generation (%)a
E. coli O157:H7L. monocytogenes
Continuous100.00 ± 75.56 A100.00 ± 34.63 A
1,000 Hz/10%265.87 ± 76.05 B160.05 ± 22.32 B
20 Hz/50%655.07 ± 51.50 C269.17 ± 18.38 C
  • a The percentage data were obtained by subtracting fluorescence values for untreated cells from those for treated cells, dividing the results by the values for cells treated with continuous UVC-LED irradiation, and expressing those values as percentages (ROS percentage = [fluorescence value after treatment − fluorescence value for untreated cells]/fluorescence value for continuously treated cells). Data represent means ± standard deviations from three replications. Values followed by the same uppercase letters within columns for each microorganism are not significantly different.