Principle of Assay
This kit provides a convenient tool for sensitive detection of beta-amylase activity. The principle is that amylase catalyzes the hydrolysis of starch to form reducing sugars, and 3,5-dinitrosalicylic acid is reduced by reducing sugar to produce a brown-red substance with an absorption peak at 540 nm; the amylase activity is calculated by measuring the rate of increase in absorbance at 540 nm. Alpha-amylase is heat-resistant, but beta-amylase can be inactivated at 70°C. Therefore, only alpha-amylase can catalyze starch hydrolysis after the crude enzyme solution is passivated at 70°C. The total amylase activity is measured with the crude enzyme solution that is not heat-treated, and the beta-amylase activity can be obtained by subtracting the alpha-amylase form total amylase activity.
