Papaya

Botanical Name(s):

Carica papaya. Family: Caricaceae

Other Name(s):

fruta bomba, melon tree, pawpaw

General Description:

The papaya is a tree that grows in the tropics. The fruit is also referred to as the papaya. The tree resembles a palm tree although the leaves are significantly different. The fruit has an excellent flavor and is imported into areas with colder climates where it will not grow. The papaya (Carica papaya), also known as the pawpaw, should not be confused with the U.S. pawpaw (Asimina triloba).

The active ingredient of the papaya tree is called papain. Papain comes from the latex (rubbery sap) of the leaves and the green fruit. Papain is a vegetable pepsin, or proteolytic enzyme (an enzyme that digests protein) derived from a plant. Papain is a powerful enzyme; purified papain will digest approximately 35 times its own weight in protein.

Papaya is used in digestive aids and in formulations to decrease edema and inflammation associated with surgical and accidental trauma.

Medically Valid Uses:

Papain is used commercially as a meat tenderizer and is available in grocery stores.

Papain is also available as a digestive aid. It may be found in combination with other enzymes such as hemicellulase, which helps break down cellulose from plants and prevent excessive gassiness.

Papain will digest non-living protein materials (fibrin, dead white blood cells, serum) but will not damage living tissue. This makes it excellent for debriding wounds. Papain is therefore available in topical ointments (Rx only) that are used to remove dead tissue and fibrin from skin lesions. Topical papain preparations are used for bed sores (decubitus ulcers), burns, diabetic ulcers on the feet and legs, and varicose ulcers.

Papain, usually in the form of meat tenderizer, can be used to treat jellyfish stings and some insect stings such as bee stings. The proteolytic action of papain quickly digests the venom responsible for the stinging, pain and inflammation. To be most effective, the papain must be applied immediately. Lifeguards on ocean beaches often keep a bottle of meat tenderizer handy just for jellyfish stings.

Recently, papain has been added in low concentration to contact-lens cleaning solutions. It removes the proteinaceous film that clings to the contacts and extends their wearing time.

Unsubstantiated Claims:

Please note that this section reports on claims that have NOT yet been substantiated through scientific studies.

There are unsubstantiated claims that papain may be useful with loss of appetite, indigestion, heartburn and various bowel disorders.

Dosing Format:

Papaya extract is available as a food supplement. Because the preparation varies so much and the product is not well described, the consumer is encouraged to use the recommended dose specified on the package.

Because potency of papain preparations varies depending on the extraction process, supplements may contain papain ranging in activity from almost inactive to fully active. Although papain can typically digest 35 times its weight of meat, it can digest 100 to 200 times its weight of the simpler protein of egg white (albumin). Papain functions best in an acid environment (pH 5) typical of the stomach. Papain-containing supplements should be used shortly after purchase. The shelf life typically is 3 to 6 months.

Women who are pregnant or breast-feeding should consult a physician before taking any herbal medicines.

Additional Information:

Click here for a list of reputable Web sites with general information on nutrition.

References:

1. Kubo S, Tajima N, Katunuma N, Fukuda K, Kuroki H. A comparative study of chemonucleolysis with recombinant human cathepsin L and chymopapain. A radiologic, histologic, and immunohistochemical assessment. Spine. 1999;24(2):120-7.

2. Dekeyser PM, Buttle DJ, Devreese B, Van Beeumen J, Demeester J, Lauwers A. Kinetic constants for the hydrolysis of aggrecan by the papaya proteinases and their relevance for chemonucleolysis. Arch Biochem Biophys. 1995;320(2):375-9.

3. Dando PM, Sharp SL, Buttle DJ, Barrett AJ. Immunoglobulin E antibodies to papaya proteinases and their relevance to chemonucleolysis. Spine. 1995;20(9):981-5.

4. Myers RI, Larsen DW, Tsao M, et al. Quantity of protein deposited on hydrogel contact lenses and its relation to visible protein deposits. Optom Vis Sci. 1991;68(10):776-82.

5. Butrus SI, Klotz SA. Contact lens surface deposits increase the adhesion of Pseudomonas aeruginosa. Curr Eye Res. 1990;9(8):717-24.

6. Begley CG, Paragina S, Sporn A. An analysis of contact lens enzyme cleaners. J Am Optom Assoc. 1990;61(3):190-4.

7. Blanco C, Ortega N, Castillo R, Alvarez M, Dumpierrez AG, Carrillo T. Carica papaya pollen allergy. Ann Allergy Asthma Immunol. 1998;81(2):171-5.

8. Mekkes JR, Le Poole IC, Das PK, Kammeyer A, Westerhof W. In vitro tissue-digesting properties of krill enzymes compared with fibrinolysin/DNAse, papain and placebo. Int J Biochem Cell Biol. 1997;29(4):703-6.

9. Walker-Renard P. Update on the medicinal management of phytobezoars. Am J Gastroenterol. 1993;88(10):1663-6.