Protease enzymes break down or change the composition of proteins or peptides. In addition to being important to the process of digestion and metabolism, some protease enzymes are thought to improve inflammation and strengthen the immune system, according to New York University Langone Medical Center. Although protease enzymes can be taken in supplement form and may be added to certain foods, these enzymes also occur naturally in certain fruits. If you are concerned about inflammation, digestive problems or any other health condition, consult your doctor.
Papaya is a very potent source of the protease enzyme papain, as well as a similar enzyme called chmyopapain. These enzymes have an anti-inflammatory mechanism, and may also play a role in healing burns, according to a 2013 issue of the "Journal of Medicinal Plants Studies." Although papain is thought to be helpful in relieving some of these health problems, it is not known to be a medical cure for any condition.
Pineapple is an excellent source of the protease-containing compound bromelain, which is thought to aid in digestion as well as in reducing blood clotting and inflammation, according to MedlinePlus.com. In addition, bromelain may have the ability to reduce the growth of certain types of tumors. However, MedlinePlus emphasizes that these benefits have not been scientifically proven, and that pineapple is not a medical treatment for any condition. Bromelain is frequently extracted from the core or stem of the pineapple for use in supplements.
Kiwi fruit contains actinidin, a proteolytic enzyme with activity similar to papain, according to Drugs.com. Actinidin comprises half of kiwi's soluble protein content. In some cases, actinidin may be an allergen, and is sometimes related to a hypersensitive reaction within minutes of eating kiwi. Kiwi fruit juice is sometimes used as a meat tenderizer, Drugs.com reports, due in part to the proteolytic activity of actinidin.