Isolation and Purification of β-galactosidase From New Born Goat Brain

β-galactosidase enzyme was isolated from the new born goat brain by nine methods, It was found that the sodium acetate 0.2 Mole/Liter +0.2Mole/Liter NaCl PH5 method have given the highest specific activity of crude enzyme in comparison with the other methods. Also, this enzyme was purified by using four methods, the second one (cold acetone) was the butter. As a result the purification fold was about 135.46 times and the yield about 77.14% by using Sephacryl S200 (second step). This enzyme is 187.437 KDa as a molecular weight.