Isolation and purification of bacterial proteinases by means of autofocusing

Autofocusing was used for the isolation and purification of neutral and alkaline proteinases from fermentation broth, after separation of cells. The yield of proteinases achieved was 19-78%, and was inversely proportional to the degree of purification, which varied from 3.0 to 7.9. Because of considerable losses of enzyme activity and the long duration of the process, autofocusing seems to be a non-economic technique for industrial isolation of relatively cheap enzymes.