ANTI-TUMOR SUBSTANCE FROM HEMOLYTIC STREPTOCOCCI AND PROCESS FOR PRODUCING THE SAME USING AMMONIUM SULFATE

摘要

1286014 Anti-tumour substance H OKAMOTO 3 Sept 1970 [6 Sept 1969] 42317/70 Heading A5B An anti-tumour substance is produced by (a) preparing an aqueous cell-free extract from living cells of haemolytic streptococci, (b) salting out the extract with (NH 4 ) 2 SO 4 and (c) collecting material precipitated at 50-80% saturated (NH 4 ) 2 SO 4 concentration. The extract may be prepared either by grinding the cells in a mortar with emery or alumina powder and then adding distilled water or saline or by suspending them in distilled water or saline and shaking them mechanically with glass beads or, treating them with an enzyme which breaks down the cell walls. In either case, the product is centrifuged to remove solid cell debris. The extract may be salted out either by dialysis or by adding (NH 4 ) 2 SO 4 directly to it. Salting out may first be carried out at 50% saturated concentration, the precipitate being discarded, and then at 80% saturated concentration to produce the desired product or the first salting out may be at 80% saturated concentration and the product from this may be redissolved and salted out at 50% saturated concentration to provide the desired product in solution. The product may be purified with an ion-exchange resin, ion-exchange cellulose, ion-exchange dextran gel, dextran gel, or calcium phosphate gel in the form of hydroxyl apatite.