IMMOBILIZATION AND KINETICS OF PENICILLIUM-NOTATUM DEXTRANASE ON CONTROLLED POROUS-GLASS

Two highly purified enzymic fractions of dextranase (1,6-alpha-D-gluca n 6-glucanohydrolase, EC 3.2.1.11) from Penicillium notatum have been immobilised on silanised porous glass modified by glutaraldehyde, carb odiimide and bis-oxirane binding. The marked shifts in the pH and temp erature optima as well as the changes in the kinetics (K-m, V-max, E-a ) of the solid-phase dextranases were observed and discussed. The immo bilisation of enzymes on alkylamine glass through the process of gluta raldehyde coupling proved to be the best of the methods studied. The d extranase preparations obtained in this way showed a catalytic activit y at wider pH and temperature ranges than those of the free enzymes. T hey were also characterized by a relatively high affinity to the subst rate and good storage stability. The usefulness of the bound dextranas e in batch and column hydrolysis of dextran was also established.