Catalytic Biotransformations by Peroxidase from Luffa aegyptiaca

Peroxidases (E.C. 1.11.1.7) are heme-containing enzymes that utilize hydrogen peroxide as an electron acceptor to catalyze oxidative reactions. The current research focuses on catalytic biotransformations addressing two environmental concerns: replacing heavy metal salt oxidations with cleaner alternatives using hydrogen peroxide or oxygen, and enhancing chemo-, regio-, or stereoselectivity in chemical reactions to improve yields and minimize waste. Peroxidases are promising in achieving these objectives. The enzyme isolated from Luffa aegyptiaca fruit juice exhibited peroxidase activity of 9.0 IU/ml with guaiacol as the substrate, monitored at λmax = 470 nm in 50 mM sodium phosphate buffer, pH 7.0. The oxidation potential for converting guaiacol to tetraguaiacol is 0.575 V, while (NH4)2(Ce(NO3)6) and (NH4)6Mo7.4H2O show potentials of 0.559V and 0.533V, respectively, indicating irreversibility. Peroxidase also oxidized Fe (II) and Mn(II) to Fe (III) and Mn(III) with a potential of 0.599V. Reaction rates using various oxidizing agents like H2O2, V2O5, VOSO4, and VO(acac)2 were evaluated, with V2O5 demonstrating superior efficacy over H2O2. The enzyme facilitated Br2 and I2 liberation in the presence of KBr/KI and H2O2 at pH 7.0, suggesting its potential as an eco-friendly reagent for halogenation in organic synthesis. Developing enzyme technology as a sustainable treatment process is recommended.