Abstract: Crude laccase was collected after fermentation broth was filtrated with vacuum pump,and then purified to electrophoretic homogeneity by the steps of ammonium sulfate precipitation,ion-exchange chromatography on DEAE-cellulose and gel filtration on Sephadex G-75. The purification of about 183.69 folds is achieved with an overall yield of 24.77%. Its molecular weight is estimated to be about 60.3 kD by SDS-PAGE. Studies on the properties of the laccase showed that enzyme activity is more stable when preserved at 30 ℃. The relative activity of laccase is above 80% when preserved at the pH range of 3.4 to 5.8,and its stability is the highest when preserved at the pH of 3.8.

Key words: Coriolus hirsutus, laccase, ion-exchange chromatography, gel filtration