Some characteristics of β-galactosidase enzyme that was isolated from a new
born goat brain were studied. This study concluded that the enzyme is glucoenzyme
in which the carbohydrate part constitutes 22.1% in accordance with
phenol –sulfate acid
method.
The optimum pH for the enzyme activity is 5.5. The enzyme lost its activity
completely at pH8.5, and showed great stability at the range of pH 4-6.
The results indicated that the optimum temperature for the enzyme activity
is 55Co at the optimum pH. The stability temperature for the enzyme is
35-60Co.
The analytical results of 5%lactose solution hydrolyzed by the enzyme have
indicated that the hydrolysis rate is between 40% after 60 minutes, to 95%
after 270 minutes.
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 ot
her 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.