M. Iscan et al., PRODUCTION OF SUPEROXIDE RADICALS BY SHEEP LIVER NITROFURANTOIN REDUCTASE - IN-VITRO EFFECTS OF NITROFURANTOIN METABOLITES ON DNA, Toxicology in vitro, 9(5), 1995, pp. 743
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.