A number of years ago we reported a two-step inactivation mechanism for α-amylase (enzyme) on the basis of theoretical and experimental studies in aqueous solutions. In the first step the metal (Ca2+) ion dissociates reversibly from the enzyme followed by an irreversible thermal inactivation of the apoenzyme. In this study we report inactivation of the enzyme in the presence of ethanol–water solutions. We noticed that as the concentration of ethanol in the aqueous solution is increased, the thermal inactivation of the enzyme is suppressed with almost no inactivation (in 1 h, 30°C) when 50% alcohol is present in the solution. These results are explained by the two-step inactivation model.
All Science Journal Classification (ASJC) codes