E. coli NCTC 12900 and S. aureus ATCC 25923 DNA quantification assay by SYBR green 1. Treatment times were 1, 3, and 5 min at 80 kVRMS with 24 h of posttreatment storage. Striped bars, E. coli NCTC 12900; dark shaded bars, S. aureus ATCC 25923. The presence of an asterisk (*) indicates a significant difference at the P ≤ 0.05 level between E. coli and S. aureus. Critical controls were provided as untreated samples with no posttreatment storage. AFU, arbitrary fluorescence units.