ptyalin or salivary amylase is a digestive enzyme present in saliva that acts on the alpha (1-4) bonds of the polysaccharides of animal (glycogen) or vegetable (starch) origin, transforming them into maltose (disaccharides).
Pthyalin is a protein secreted by the salivary glands, especially in the parotid gland, and it works most efficiently at neutral or slightly alkaline pH. The word "ptialin" comes from the Greek Ptyalon, which means Spittle.
The function of ptyalin is to initiate the digestion of polysaccharides (carbohydrates) in the mouth, "breaking" these molecules and transforming them into smaller sugars (oligosaccharides, disaccharides and monosaccharides), which, in turn, are "broken down" in the small intestine by amylases from pancreatic juice and enteric juice, until they are transformed into glucose and thus absorbed by the body in the intestine.
Pthyalin acts as a catalyst in the hydrolysis of starch, which turns it into simpler sugar molecules.
Once in the stomach, the pthyalin swallowed with food is automatically neutralized by the acidic environment of the stomach.