Digestive enzymes are enzymes in the alimentary tract with a purpose of breaking down components of food so that they can be taken up by the organism. The main sites of action are the buccal cavity, stomach, and the jejunum. They are secreted by the salivary glands, the stomach, and the pancreas. The main digestive enzymes are:

• Amylase, which digest starch into small segments of multiple sugars and into individual soluble sugars.
• Protease, which split up proteins into their component amino acids.
• Carbohydrase, which split up animal and vegetable fats and oils into glycerol and fatty acids.
• Lipase, which breaks down fatty acids.