THE EFFECTS OF TEMPERATURE CHANGES ON SALIVARY AMYLASE ACTIVITY

¹ Dental Department, Montefiore Hospital, New York, N. Y.

The amylolytic activity of salivary amylase increases with a rise in temperature up to 50° C. As the temperature is raised beyond this optimum point, amylase activity drops off rapidly. The increase in activity with a rise in temperature up to 500° C. is due to the accelerating effect of increased temperature on the native amylase-starch reaction. The heat of activation for this reaction is 22,742 calories.

The decrease in amylase activity which accompanies a rise in temperature above 50° C. is due to inactivation of the amylase. The high heat of activation (62,342 calories) characterizing this process marks it as a denaturation.

One stage in the denaturation of salivary amylase is readily reversible. The denaturation process may be slowed by the presence of substrate and by NaCl.