Magnetic Graphene Oxide as a Carrier for Lipases Immobilization: An Approach for Hydrolysis of Olive Oil Emulsion

Abstract

The use of lipases in industrials processes has increased due to its ability to catalyze total or partial hydrolysis reactions of fatty acids. However, due to the difficulty of isolation and purification of lipases, as well as its separation from the reaction medium, it becomes an expensive input. In this study, graphene oxide was used as carrier for enzymes. The magnetic properties of the carrier were obtained through decoration with magnetic iron oxide nanoparticles on graphene oxide surface.XRD was used to elucidate the structure and morphology of the compounds obtained. By measuring hydrolytic activity, it was possible to determine the optimum pH and temperature for three different types of immobilized lipases, being 37 °C and pH 8 (porcine pancreatic lipase), 50 °C and pH 6 ( Candida rugosa lipase), and 40 °C and pH 9 ( Aspergillus niger lipase). The enzymatic recovery test, during five minutes each, showed the immobilized porcine pancreatic lipase can be recycled six times without significant loss of catalytic activity. It was confirmed the efficiency of the magnetic graphene oxide as a carrier for different lipases allowing its use for transesterification process in mild temperature and pH conditions.