... nitrobenzene, dinoseb and nitrofurazone, with the highest activity for nitrofurazone. The flavin reductase activities of DrgA protein forFAD and FMN were 7.41 and 6.95 UÆmg)1protein,respectively, in the ... buffer,pH 7.0, in another aerobic cuvette, and air was substitutedwith argon for 15 min. The anaerobic cuvette and the tubewere warmed at 30 °C for 5 min, and the initial concentra-tion of NADH was ... measuring the consumption of NADH at 340 nm. In parallel, the amount of hydrogen peroxide and hydroxylradicals was measured before and after the reaction. The quantitation of hydrogen peroxide and...