Separation And Purification Of Soybean Hulls Peroxidase Study

Peroxidase[POD, EC1.11.1.7 (x) ] is a kind of redox enzyme with hemoglobin as prostheric group, which widely exists in organism and has many different biological functions. It mainly catalyzes the oxidation of hydrogen peroxide and organic peroxide with many inorganic and organic substances. For the high specificity and sensitivity, it is widely applied in protein, polypeptide, hormone, virus, parasite, lignification, biology degradation and neuro-system etc.One of the most widely studied peroxidase is horseradish peroxidase(HRP). Soybean hull peroxidase (SHP) obtained from the soybean hull coats belongs to class III of the plant peroxidase superfamily, similar to HRP. It contain about 300 amino acids with a mean molecular mass of 37kD .This enzyme accounts for up to 5% of the total soluble protein of the hull, and is believed to be on of the richest sources of peroxidase.SHP was extracted by phosphate buffer and purified by ammonium sulfate precipitaion and acetone precipitation, ion exchange chromatography using DEAE Sepharose Flast Flow column, and gel filtration using Sephadex G-75 column. The specific activity of the purified enzyme increased 33.7 fold over the crude extract with 46.1% recovery. At the same time, a systematic evaluation of the biocatalytic properties of SHP was carried out. The effects of pH and temperature on the enzymatic activity of the peroxidase were assayed. The results show that SHP is able to retain its catalytic activity under wide of pH and at elevated temperatures.