Continuous optical assay of sucrase and other glucosidases

A continuous optical method for the assay of glucose-releasing hydrolases is reported. Particular emphasis is given to the assay of purified sucrase from rabbit small intestine. The procedure requires glucose dehydrogenase and mutarotase. In the presence of the latter enzyme, the initial lag is substantially shortened when glucose is released as alpha-anomer. Under the test conditions used, the method shows a good proportionality up to an activity of 0.2 units/3 ml and may also be applied for measuring the activity in crude homogenates.