Maltase

MALTASE, an enzyme from the carbohydrate group (see), that produces hydrolytic cleavage of maltose into 2 molecules of glucose. M. is contained in almost all plant and animal cells, in the blood of some animals, in intestinal and pancreatic juice; the presence of M. in saliva is disputed by recent authors (Pringsheim, Leibowitz). Particularly rich in M. are yeast and germinating seeds (malt), and among animal organs—the liver. M. is easily destroyed by alkalis and especially by acids, acting optimally at a neutral reaction. The temperature optimum is at 40°; heating to 55° destroys M. In the animal organism, M. participates in the formation of glucose from glycogen, together with amylase, which breaks down glycogen to maltose. The synthesis of glycogen in the liver is also probably carried out by M. and amylase. Besides maltose, M. also breaks down some other glycosides of the alpha-series (for example, alpha-methyl and alpha-phenyl glycoside). To detect M., an extract from the corresponding organ is steeped with a 5% solution of maltose in the presence of toluol for 24 hours, and then tested for the presence of glucose (phenylhydrazine test, increase in reducing power of the liquid).