Reduction of nitro phenols using nitroreductase from E. coli in the presence of NADH

The reductions of nitrophenols catalyzed by nitroreductase from E. coli in the presence of NADH were investigated in this paper. 4-Aminophenol and 4-hydroxylaminophenol were found in the reductive products of 4-nitrophenol and the maximum reductive ratio was about 83.49% when the reaction time was 70 min; 4,6-dinitro-2-pimelie kelone was found in the reductive products of 2,4-dinitrophenol and the maximum reductive ratio was about 75.28% when the reaction time was 80 min; 2,4-dinitrophenol and 4,6-dinitro-2-pimelie kelone were found in the reductive products of 2,4,6-trinitrophenol and the maximum reductive ratio was about 62.08% when the reaction time was 100 min. The similar reductive ratios of nitrophenols were obtained under aerobic and anaerobic conditions. The results indicated that nitroreductase was an oxygen-insensitive enzyme.