IMMOBILIZATION OF TYRAMINE-HRP ONTO TYRAMIDECARBOXYMETHYL CELLULOSE MATRIX FOR WASTEWATER TREATMENT

Abstract

Horseradish peroxidase (HRP, E.C. 1.11.1.7) catalyzes oxidation of aqueous aromatic compounds using hydrogen peroxide. Enzymatic treatment methods for phenol removal from wastewaters has become an efficient and environmentally friendly alternative for the traditional methods. Carboxymethyl cellulose (CMC) derivative with tyramine attached via amide bond to carboxyl groups has been chosen as carrier for immobilization. In effort to overcome the main disadvantage of entrapment immobilization method, loss of enzyme activity due to washing out from the carrier, HRP was modified in a reductive amination reaction and tyramine was bound to the enzyme. Immobilization of tyramine-HRP onto tyramide-carboxymethyl cellulose carrier was carried in an emulsion polymerization reaction that produced carboxymethyl cellulose microbeads. The highest specific activity of the obtained biocatalyst was 0.227 U/ml and after 48h of storage 0.197 U/ml. Immobilized tyramine-HRP retained 87% of activity after 48 h. Immobilized HRP is a suitable candidate for wastewater treatment.