Nitration Reaction Catalyzed by Horseradish Peroxidase in the Presence of H₂O₂ and NaNO₂

The enzymatic nitration of phenol and m-cresol catalyzed by horseradish peroxidase was studied in the presence of H₂O₂ and NaNO₂. The results showed that the nitration products of phenol were 2-nitro and 4-nitrophenols. There was also a small amount of by-products of hydroquinone and catechol. The influences of various reaction parameters, including pH, organic solvent type, and concentrations of NaNO₂ and H₂O₂, on the nitration products were investigated. The yields of 4-nitrophenol and 2-nitrophenol were 14% and 12%, respectively. The nitration products of m-cresol were 4-nitro-m-cresol and 6-nitro-m-cresol, and the yields of 4-nitro-m-cresol and 6-nitro-m-cresol were 19% and 30%, respectively.