EXTRACTION an‎d PURIFICATION OF β-galactosidase FROM NEW BORN SHEEP BRAIN.

β -galactosidase enzyme was extracted from the new born sheep brain by nine solutions, It was found that the0.2 M sodium acetate and 0.2M NaCl give a highest specific activity of crude enzyme. This enzyme was concentrated by four methods, includes: concentration by ammonium sulfate (20-60%); old acetone; ethanol (30%- 60%) and by ultra filtration. It was found that the cold acetone was the better. The purification folds were about 124.78 times and yield about 77.39%. The molecular weight of this enzyme about 185.942 Kilo Dalton.