Note: Do not rely on this information. It is very old.
Ptyalin
Ptyalin, proteid substance existing in the saliva of the mouth. In its composition it closely resembles mucin (q.v.). It is soluble in water, and induces a fermentive change in starchy matters whereby they pass into soluble sugars. Hence it plays an important part in digestion in aiding the assimilation of the otherwise insoluble starch and allied compounds. [Digestion.]