PRODUCTION OF SUPEROXIDE RADICALS BY SHEEP LIVER NITROFURANTOIN REDUCTASE - IN-VITRO EFFECTS OF NITROFURANTOIN METABOLITES ON DNA

The reduction of nitrofurantoin by purified liver nitrofurantoin reduc tase was followed by the production of superoxide radicals, which were detected by the reduction of epinephrine. The conditions for the form ation of superoxide radicals were optimized. The maximum superoxide ra dical formation occurred at approximately 3.5 mu g purified reductase, with optimum pH of 7.8 and at 0.05 mM nitrofurantoin concentration. T he K-m and V-max values were calculated as 1.95 x 10(-2) mM and 4.81 n mol superoxide formed per minute. An obliteration of the banding patte rn was observed on the agarose gel electrophoresis of sheep liver DNA, which was incubated in the nitrofurantoin-nitrofurantoin reductase sy stem, as a possible consequence of the generation of superoxide radica ls during the reduction of nitrofurantoin by nitrofurantoin reductase.