Carica papaya


 * Not to be confused with the American fruit called "pawpaw", Asimina


 * Not to be confused with Chaenomeles speciosa or Pseudocydonia sinensis, which like the Carica papaya are called "mugua"

Carica papaya (papaya, papaw, pawpaw) is a species of flowering plant in the Caricaceae family, as the sole member of the Carica genus. It is endemic to the tropics of the Americas, and was first cultivated in Mexico several centuries before the Mesoamerican classic cultures emerged.

It is a tree-like plant, growing on a single stem 16 to 33 feet tall, with leaves spirally arranged at the top. The lower part of the trunk is conspicuosly scarred where the leaves and fruit are borne. The leaves reach sizes between 20-28 inches in diameter and deeply palmately lobed with 7 lobes. The plant is usually unbranched if unlopped. The shape of the flowers is similar to the Plumeria, but are much smaller and wax-like. These appear on the axils of the leaves, and will eventually mature into a fruit, 5.9 to 18 inches long, and 3.9 to 12 inches in diameter. The fruit is ripe when it feels soft, and its skin is colored amber to orange.

It is the first fruit tree to have its genome deciphered.

Common names
In North America, the name "pawpaw" may also refer to an unrelated North American genus, Asimina; however, pawpaw and papaw are common synonyms of papaya in North America and other places. It is sometimes called mugua, and is sometimes confused with Chaenomeles speciosa or Pseudocydonia sinensis, which are called mugua in Traditional Chinese Medicine.

More translations and common names are found on Wiktionary.

Cultivation
The papaya was originally found from southern Mexico, particularly in Chiapas and Veracruz, Central America, and northern South America, but is now cultivated in most tropical countries, including Brazil, Bangladesh, Pakistan, India, Indonesia, South Africa, Sri Lanka, Vietnam, the Philippines, and Jamaica. In cultivation, it will grow rapidly, fruiting within 3 years. It is, however, highly sensitive to frost.

The fruit is susceptible to the papaya fruit fly (Toxotrypana curvicauda), which lays its eggs inside younger fruits.

During the 1990's, the papaya ringspot virus (Potyvirus) threatened to completely wipe out Hawaii's papaya industry. Two varieties of papaya, Carica papaya 'SunUp' and Carica papaya 'Rainbow', that had been genetically modified to be resistant of the virus were introduced to Hawaii. By 2010, 80% of papaya from Hawaii was genetically modified. Today, there is still no conventional or organic way of controlling the papaya ringspot virus. In 2004, genetically modified and organic papayas through Hawaii experienced hybridization.

Uses
Papayas are used for a number of things. The fruits are often times used as a food, in cooking aids, and in medicine. The stems and bark are sometimes used in rope production.

Gastronomy
The ripe fruit is usually eaten raw, without the skin or seeds. The unripe green fruit of the papaya can be eaten cooked, and is sometimes found in curries, salads, and stews. It has a relatively high amount of pectin, which can be used to make jellies.

Green papaya is used in Thai cuisine, both raw and cooked.

The black seeds are edible, and may have a sharp, spicy taste. They are sometimes ground up and used as a substitute of black pepper. In some parts of Asia, the leaves are steamed and eaten like spinach. In parts of the world, papaya leaves are made into a preventative for malaria, but there is no real scientific evidence on how this is effective.

Cooking
Green papaya fruit and the tree's latex are both rich in papain, which is useful in tenderizing meat and other proteins. Its ability to break down tough meat fibers was used for a long time by indigenous Americans. It is included as a component of powered meat tenderizers.

Medicine
Papaya is marketed in the form of a tablet to remedy digestive problems.

Papain is also used topically in the countries it is found for treating cuts, rashes, stings, and burns. Papain ointment is commonly made from fermented papaya flesh, and is applied as a gel-like paste.

Women in India, Bangladesh, Pakistan, Sri Lanka, and other countries have used green papaya as a folk remedy for contraception and abortion. Enslaved women in the West Indies sometimes consumed papaya to prevent pregnancies, so that their children couldn't be born into slavery. Medical research in animals confirmed the contraceptive and abortifacient capabilities of the papaya, and also found that the seeds have contraceptive effects in male langur monkeys, and possibly in male humans as well. Unripe papaya is especially effective in large portions. Ripe papaya is not teratogenic, and will not cause miscarriage in small amounts. Phytochemicals in papaya may suppress the effects of progesterone.

Allergies and side effects
Papaya is frequently used in hair conditioners, but should be used in small amounts. Papaya releases a latex fluid when it is not quite ripe, which can cause irritation, and provoke allergic reactions with some people. The papaya fruit, seeds, latex, and leaves contains an anthelmintic alkaloid, carpaine, which can be dangerous in high doses.

It is speculated that unripe papayas may cause miscarriages because of the latex content, which may cause uterine contractions. Papaya seed extracts in large doses have a contraceptive effect on rats and monkeys, but in small doses have no effect on the unborn animals.

Excessive consumption of papaya can cause carotenemia, a harmless disease that causes yellowing of the soles and palms. However, a very large dose would need to have been consumed, because papaya contains about 6% the level of beta carotene found in carrots per 100 grams.

Medicinal potential
The juice has an antiproliferative effect on vitro liver cancer cells, probably due to its component of lycopene.

Papaya seeds could be used as an antibacterial agent for Escherichia coli, Staphylococcus aureus, or Salmonella typhi, although further research is needed before advocating large-scale therapy.

Papaya seed extract may be nephroprotective in toxicity-induced kidney failure.

Diseases

 * See List of papaya diseases