[The use of ultrafiltration for concentration and purification of beta-galactosidase]

A possibility of concentration and purification of culture fluid of Escherichia coli by the ultrafiltration technique using Soviet cellulose acetate membranes were studied. It is established that cellulose acetate membranes may be used for purification from low molecular weight protein and concentration of preliminarily purified culture fluid of Escherichia coli. Membranes YAM-300 are most preferable. At the temperature of 18 degrees C, pressure 0.16-0.24 MPa and 20-fold concentration the yield of the enzyme at the ultrafiltration stage was 84.5%.