Vermiculite as an economic support for immobilization of neutral protease

A new and cheap support, vermiculite was successfully used to immobilize neutral protease by adsorption and hexamethylene diamine mediated coupling using glutaraldehyde as a bifunctional agent. Neutral protease immobilized on vermiculite by adsorption showed maximum retained activity than HMD mediated coupling. The optimum temperature for both free and immobilized neutral protease was found to be 45°C. However, the pH and thermal stabilities of immobilized neutral protease was observed to be better than that of the free enzyme. The storage stability of the immobilized enzyme was also studied. © 1992 Springer-Verlag.