Process for producing arginase

Claim 1

IN A PROCESS FOR PRODUCING ARGINASE, THE IMPROVEMENT WHICH COMPRISES DRYING BIOLOGICAL TISSUE, ADMIXING THEREWITH WATER CONTAINING AT LEAST ONE ACTIVATOR FOR ARGINASE CHOSEN FROM THE GROUP CONSISTING OF COBALTOUS NITRATE, COBALTOUS SULFATE, MANGANOUS SULFATE AND MANGANOUS DIHYDROGEN PHOSPHATE WHILE MAINTAINING SAID ADMIXTURE AT A PH OF FROM 7.0 TO 9.5 SEPARATELY RECOVERING THE LIQUID PORTION OF SAID MIXTURE, EXTRACTING SAID LIQUID PORTION WITH FROM OVER ONE-HALF TO THREEFOURTHS ITS VOLUME OF ACETONE WHILE MAINTAINING SAID EXTRACTION MIXTURE AT NOT OVER ABOUT 5* C., WHEREBY PROTEINS ARE PRECIPITATED, RECOVERING THE LIQUID PORTION OF SAID EXTRACTION MIXTURE, ADMIXING SAID LIQUID WITH A SECOND PORTION OF FROM OVER ONE-HALF TO THREE-FOURTHS IT VOLUME OF ACETONE WHILE MAINTAINING SAID MIXTURE AT NOT OVER ABOUT 5* C., WHEREBY AN ARGINASE-ENRICHED FRACTION IS PRECIPITATED, DISSOLVING SAID PRECIPITATE IN WATER HEATING SAID SOLUTION TO FROM 60* C. TO 80* C., RAPIDLY COOLING SAID SOLUTION TO NOT OVER 3* C., WHEREBY A PRECIPITATE IS FORMED, SEPARATELY RECOVERING THE SOLUTION PORTION, ADMIXING WITH SAID SOLUTION PORTION A LEAD SALT IN AMOUNT TO PROVIDE NOT OVER 0.25 MG. OF LEAD IONS PER CC. OF SOLUTION, WHEREBY A PRCIPITATE IS FORMED, SEPARATELY RECOVERING THE RESULTANT SOLUTION PORTION, ADMIXING WITH SAID RESULTANT SOLUTION FROM MORE THAN ONE-HALF TO ABOUT THREE-FOURTHS VOLUME OF ACETONE WHEREBY A PRECIPITATE IS FORMED, SEPARATELY RECOVERING THE SOLUTION PORTION, ADMIXING THEREWITH AT LEAST ONE-HALF ITS VOLUME OF ACETONE, AND RECOVERING THE RESULTANT PRECIPITATE.