GB651545A - Improvements in or relating to the preparation of enzymes - Google Patents

Abstract

Hyaluronidase is prepared from finely-divided mammalian testicular tissue by adding water thereto, adjusting the pH of the aqueous mixture to 4.5-4.7 (preferably 4.6), separating the solid material after prolonged stirring (preferably for at least 12 hours), adjusting the pH of the liquid to 7.5-9.2 (preferably 8.0-8.2), separating the resulting precipitate of inactive solid material, adjusting the pH of the liquid to 4.6-7.1 (preferably 4.6-5.2), adding ammonium sulphate (preferably by dialysis) in such amount that the liquid is 25-30 per cent saturated therewith, separating the further precipitate of inactive solid material, readjusting the pH of the liquid to 4.6-7.1 (preferably by dialysis) until the liquid is 60-80 per cent saturated therewith, thereby precipitating hyaluronidase, which is separated from the liquid and may be redissolved in water and the solution dialysed against running water, filtered and evaporated to dryness, the whole process being conducted at a temperature of 1-5 DEG C. The product may be further purified by alcohol fractionation or a second fractionation with ammonium sulphate. An example describes the application of the process to bull testes, which are prepared for treatment by freezing, removing the outer membrane, grinding to powder in the presence of dry ice, allowing to come to room temperature and further grinding in a Waring blender. The Specification as open to inspection under Sect. 91 comprises the use of a pH range up to 5.7 in the first step of the process. This subject-matter does not appear in the Specification as accepted.