Hog Intestinal Isomaltase Activity.

Abstract

Homogenates of hog intestinal mucosa have isomaltase activity, caused by at least 3 different enzymes. About 3/4 of the total isomaltase activity is caused by an enzyme (or enzymes) which seems to have mainly isomaltase activity. This enzyme has no invertase or maltase activity, but it possibly hydrolyzes phenyl-[alpha]-D-glucopyranoside. The name specific isomaltase is suggested for this enzyme. The remainder of the isomaltase activity is caused by 2 hog intestinal maltases, which hydrolyze isomaltose slowly. Separation of the specific isomaltase from the other hog intestinal [alpha]-D-glucopyranosidases was not successful. It could be stated, however, that the specific isomaltase transglycosylase properties which clearly differ from those of the isomaltase activity accompanying the 2 maltases. The influence of freezing and thawing upon the specific isomaltase activity is complex, and involves a decrease as well as an increase of this activity.