Influence of CeO 2 nanoparticles synthesized from plant extracts on the catalytic performance of isolated catalase from carrots

This paper describes the green synthesis of well-crystalline CeO 2 nanoparticles (NPs) using the extract of lemon leaves ( Citrus limon ) and efficiently used as substituted catalase to catalyze the various catalase enzyme. The spherical particles along with typical face-center cubic crystalline phase were observed for CeO 2 NPs which were further characterized in terms of compositional, structural, surface, and enzyme catalytic properties. Catalase was isolated from carrots ( Daucus carota ). The optimum pH and temperature for catalase activity was found to be 6.0 and 35 °C, respectively. K m value was found to be 17 mM calculated from the double reciprocal plot. The enzyme was found to be an eco-friendly reagent for oxidation of toxic compounds like phenols, acetaldehydes, acetic acid, and sodium nitrite. CeO 2 nanoparticles biomimic catalase and degrade H 2 O 2 efficiently. Optimum pH and temperature for catalase-like activity by CeO 2 nanoparticles were found to be 6.0 and 30 °C, respectively. K m value was found to be 14.96 mM from the double reciprocal plot. Comparative studies of catalase and CeO 2 nanoparticles with respect to kinetic parameters like pH, temperature, and Michaelis–Menten constant K m have been established.