Abstract:

Both o-nitrophenyl β-D-galactopyranoside(ONPG) method and disaccharase method are commonly used for the determination of lactase activity. This paper compared the linear range, detection limit, precision, accuracy and stability of these two methods. It is found that ONPG method is better than disaccharase method in linear range, detection limit, precision and stability, but this method has poor repeatability and needs further optimization.

Key words: o-nitrophenyl-β-D-galactopyranoside, disaccharase method, lactase activity, methodological comparison