A form of amylase found in the saliva of humans and some other animals.‘It begins in the mouth where the enzyme ptyalin, present in saliva, begins to break down starch in food to sugars.’
- ‘The saliva of carnivora contains no ptyalin and cannot predigest starches; that of vegetarian animals contains ptyalin for the predigestion of starches.’
Mid 19th century from Greek ptualon ‘spittle’+ -in.
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