Über die Auswertung von Pepsinpräparaten und die Einheitlichkeit der Magenprotease

Abstract

Various methods of pepsin estimation are compared. The method of Anson or a modified digestion of egg protein with accurate determination of the undigested residue proved to be the most suitable. It is unnecessary to postulate a stomach cathepsin in addition to pepsin. The apparent difference in the temperature stability of the 2 hypothetical components is due to an incorrect interpretation of the low stability of pepsin towards high hydrogen ion concentrations. The proteolytic activity of pepsin ranges from pH 1.8.-3.8; it depends not only on the temperature and pH but also on the kind of substrate and of acid anion.