OP-II-3

PP-III-72HORSERADISH PEROXIDASE IMMOBILIZATION IN CATALYTICOXIDATION OF PHENOLSSulman M., Sidorov A., Lakina N., Sulman E., Tikchonov B.,Matveeva V., Doluda V.Dept. of Biotechnology and Chemistry, Tver Technical University, A. Nikitin str., 22,Tver, 170026 (Russia) sulman@online.tver.ruThe use of the immobilized enzymes in modern industrial catalysis is in greatdemand. These are the major reasons for attaching enzymes to various supports: (i)multiple or repetitive use of a single batch of enzymes; (ii) the ability to stop thereaction rapidly by removing the enzyme from the reaction solution; (iii) enzymes areusually stabilized by binding; (iv) product is not contaminated with the enzyme; (v)analytical purposes - long 1/2-life, predictable decay rates, elimination of reagentpreparation. The surface on which the enzyme is immobilized is responsible forretaining the structure in the enzyme through hydrogen bonding or the formation ofelectron transition complexes. These links will prevent vibration of the enzyme andthus increase thermal stability. The microenvironment of the surface and the enzymehas a charged nature that can cause a shift in the optimum pH of the enzyme of up to2 pH units. Thus, while developing reusable catalytic systems on the basis ofimmobilized enzymes one of the main problems is the choice of the firm carrier forthe immobilization of enzyme which will provide its best stabilization. The applicationof traditional (alumina, silica, ion-exchange resins) and polymer-modified supports isan effective solution to this problem.In this study the catalytic systems on the base of immobilized horseradishperoxidase (HRP) were successfully applied in the reaction of phenol oxidation in thepresence of hydrogen peroxide. Various catalytic systems were synthesized: (i) HRPimmobilized on alumina modified with polyelectrolytes (chitosan (CS) andpoly(sodium 4-styrenesulfonate)), (ii) HRP immobilized on CS-modified cationexchangeand anion-exchange resins. Carbodiimide (CD) and glutaric aldehyde wereused as linking agents.The extraction of HRP was carried out from disintegratedfresh root of horseradish. The activity of the obtained catalyst on the base of ionexchange resins remains practically constant at the repeated application in thereaction of phenol oxidation. Among the catalysts on the base of ion-exchange resinsCS-modified cation-exchanger was the most effective one (99.5 % of phenol574