Peroxidase from green zucchini (Cucurbita pepo L.) immobilized on natural polymers removes phenolic compounds from water samples

Abstract

Phenolic compounds occur in effluents from a wide variety of industrial operations, and they present toxicity and generate environmental problems. The treatment of these wastes via enzyme immobilization indicates that peroxidase (E.C.1.11.1.7) is the enzyme with the widest application. In the same process, biodegradable polymers have generated significant interest from research and industrial communities. Here we applied biopolymers from sugarcane bagasse (SB) and Cerrado cashew-tree polysaccharide (PEJU-GO) as supports for peroxidase immobilization from crude green zucchini extract via physical adsorption and covalent bonding. In addition, we used these systems in the removal of phenols from industrial effluents. Electron microscopy showed a fibrous surface for SB and a microporous material for PEJU-GO, characteristics that facilitate the immobilization. The infrared of both materials elucidated characteristic bands of sugars. For operational stability after 30 days of storage, the immobilized peroxidase retained 69 and 50% activity for SB and PEJU-GO, respectively. The systems were able to remove up to 79% of phenolics from industrial wastes. Therefore, the biopolymers from sugarcane bagasse and cashew-tree polysaccharide are promising sources for biotechnology, especially when used for peroxidase immobilization. This will support enzymatic activity in laboratory practice, with homogeneous behavior in different pH conditions, at low cost, biodegradable, non-toxic and extracted in a sustainable way.