The three main classes of digestive enzymes are: Amylase (breaks down carbohydrates into simple sugars> monosaccharides, disacch...The three main classes of digestive enzymes are: Amylase (breaks down carbohydrates into simple sugars> monosaccharides, disaccharides), Protease (breaks down proteins into amino acids> mainly trypsin and chymotrypsin) and Lipase (breaks down the fats (lipids) into fatty acids ).