Lactase

Lactase, an enzyme from the group of carbohydrates (see), which produces the hydrolytic cleavage of milk sugar (lactose) into glucose and galactose. L. is contained in kefir grains, in Aspergillus Oryzae and some other microorganisms, as well as in commercial emulsin. In the animal organism, L. is found in young mammals (calf, puppy, etc.) in the mucous membrane of the intestinal wall, as well as in adult animals when fed milk; L. does not pass into the intestinal juice (Oppenheimer). It is also contained in the intestine of Helix pomatia L. For the detection of L., the tested aqueous extract is infused for a day with a 5% solution of milk sugar at body temperature in the presence of toluene, and then the¹ phenylhydrazine test for glucose is performed (see Glucosazone).