توصيف إنزيم ال β-Galactosidase المستخلص و المنقى من ضرع البقر

الملخص EN

Some characteristics of the enzyme β-galactosidase extracted and purified from the udder of cowswere studiedin the laboratory of Graduate Studies in the Department of Science - College of Basic Education - University of ALMustansiriya.

This study had confirmed that this enzyme is glycoprotein in which the carbohydrate part constitutes (20.5%) according to phenol –sulfate acid method, and its molecular weight was 176.620 KD as estimated by gel filtration.

The total enzymatic effectiveness was(3000) units/ ml at the optimized pH5.5, for enzyme activity, the enzyme had lost its activity completely at pH (9), and showed high stability at the pH (4 - 6.5).

The results showed that the optimum temperature for the highest enzyme activity (1800 Units/ ml )was (55)C° at the optimized pH, The temperature stability of the effectiveness of the enzyme ranged between (30-60)C °.

And the ability of the enzyme to hydrolyze lactose, ranged between (22%) after (30) minutes to (92%) after (270) minutes.