Characteristics of a Simple Assay Method for .ALPHA.-Amylase Using Microplates.

The characteristics of a novel method of α-amylase activity determination were investigated. The principles of this method were based on the light absorbance change through a gelatinized starch-agar gel fixed in a well of a microplate caused by α-amylase action. α-Amylases from different origins were successfully measured. The results of α-amylase activity in enzyme formulations and rice koji extractions measured by this method were in agreement with the values obtained by the conventional method. Since the microplate method is only able to measure α-amylase activity selectively, this method is considered to be extremely practical for quick, multisample treatment.