Abstract

In this work, we compared some methods of urease preliminary purification: ammonium sulfate fractionations, acetone precipitation, gel filtration chromatography and ultrafilter. Determination of enzym fold pury and recovery yield, acrylamid-gel electrophoresis of urease from each method showed amonium sulfate fractionations with 65% and 55% saturated concentrations was the most effective. Purification was carried out continuously by DEAE-cellulose column, the chromatograph showed three peak protein and only one peak urease at 0,3 M salt concentration. Acrylamid-gel electrophoresis of urease of the highest specific activity peak indicated that soybean urease was homogeneous enzym. The result of electrophoresis indicated our purification process was effective and pure urease was obtained.