Purification And Characterization Of Isoquercitrin-β-glucosidase

In this paper,isoquercitrin-(3-glucosidase was purified from Absidia sp.R9g.The enzymatic properties were also studied,including effect of temperature,pH and mental ions on enzyme activity and enzymatic reaction kinetics.The isoquercitrin-β-glycosidase was purified from Absidia sp.R9g using Sephadex G-100 and DEAE-cellulose columns.The purity and molecular mass of the glycosidase were determined using SDS-polyacrylamide gel electrophoresis.The purified enzyme migrates as a single band on the SDS-PAGE and its molecular mass was determined to be about 50 kDa.The optimum temperature and pH of isoquercitrin-β-glucosidase was 50℃ and pH 5.0,respectively.This enzyme was stable at pH 3.0-7.0,below 60℃.The activity of this enzyme was not obviously affected by Na+,K+,Ca2+ions,but strictly inhibited by Fe3+and Cu2+.The Vmax and Km for isoquercitrin-β-glucosidase was 3.26 mmol/L·h and 57.6 mmol/L,respectively.