Correlation between DNA-breaking activity of aminosugars and the amounts of active oxygen molecules generated in their aqueous solutions.

The generation of active oxygen molecules, O2-, H2O2, and OH, from the aqueous solution of aminosugars, such as D-glucosamine, was confirmed by their actual measurement. Both the C-2 amino and C-1 aldehyde groups in the aminosugar molecules were indispensable for the generation of active oxygen molecules. The introduction of a C-6 phosphate group to D-glucosamine or the simultaneous use of phosphate ion and D-glucosamine heightened the original activity of D-glucosamine to generate these oxygens, especially OH. Cu2+, which promoted the DNA-breaking activity of aminosugar most at 1 millimolar, also promoted the generation of OH most greatly at the same concentration, but neither O2- nor H2O2 was generated under the same conditions. Superoxide dismutase, catalase, and some radical scavengers inhibited the generation of these active oxygen molecules. Among the active oxygen molecules, only the amount of OH generated was directly proportional to the DNA-breaking activity of the aminosugar.