[Application of the ultrafiltration method to the isolation of cholesterol oxidase of microbial origin].

Ultrafiltration of solutions of intracellular cholesterol oxidase of Actinomyces lavendulae through semi-permeable membranes (N-vinyl pyrrolidone and methacrylate copolymers) of varying porosity and acetyl cellulase ultrafilter UAM-200 M was investigated. The ultrafiltration through membranes of both types involved both concentration and purification of cholesterol oxidase from low molecular weight protein admixtures. When copolymer membranes were used, their performance and degree of purification were higher and losses were lower than in case of UAM-200 M filter. The optimum hydrolytic mode of ultrafiltration of intracellular cholesterol oxidase through both filters was determined.