Protective effect of ascorbic acid against double-strand breaks in giant DNA: Marked differences among the damage induced by photo-irradiation, gamma-rays and ultrasound

- Double-strand breaks, DSBs, in genomic DNA were evaluated.
- Single DNA molecular observation was applied to analyze DSB quantitatively.
- Protective effect of ascorbic acid on DSBs against reactive oxygen was confirmed.
- Ascorbic acid did not decrease DSBs caused by ultrasound.
- Intermediate protection of ascorbic acid was found against γ-ray irradiation.