AN IMPROVED METHOD OF MEASURING GLUCOAMYLASE ACTIVITY IN THE PRESENCEOF ALPHA-AMYLASE

An improved method of glucoamylase activity assay is proposed. The met hod has the following advantages: (1) The glucoamylase-catalyzed hydro lysis reaction of substrates and enzymatic measurement of glucose are done in one tube. (2) No special equipment or techniques are required. (3) The assay is accomplished in a short time. The results obtained b y the present method (x) correlated well with those by the general met hod (y), calculated by the equation y=28.56 x-0.066. There was no diff erence among soluble starch, G5 or G7 as a substrate. Contamination of alpha-amylase did not influence the glucoamylase activity at less tha n 12,000 U/ml.