DNA Breakage by Hydrolyzable Tannins in the Presence of Cupric Ion

Abstract
DNA breakage by hydrolyzable tannins of known structures was investigated by agarose or polyacrylamide gel electrophoretic analysis. Hydrolyzable tannins could cause both double-strand and single-strand breakages in λDNA in the presence of Cu2+. The breaking reaction was strongly suppressed at concentrations higher than 100 μm of hydrolyzable tannins. DNA breakage by various tannins was dependent upon their sorts, numbers, and binding sites of the constituent acids and polyalcohols. Metallic ions other than Cu2+ had little effect on the breaking reaction.