Stabilization of cetyltrimethylammonium bromide permeabilized yeast whole cell lactase

Summary Cetyltrimethylammonium bromide-permeabilized cells ofK. fragilis loose -galactosidase activity due to leaking of the enzyme into the medium. This leakage of the enzyme can be prevented by storing the permeabilized cells either in buffer containing 50% glycerol or by treating the permeabilized cells with 0.2% glutaraldehyde at 4°C for 10 min. In repeated batch hydrolysis of lactose in milk, glutaraldehyde treated cells could be repeatedly used very efficiently.