Papaya

From Wikipedia, the free encyclopedia

This article is about Carica papaya, the widely cultivated papaya (or papaw or pawpaw), a tropical fruit tree. For the mountain papaya (Vasconcellea pubescens) of South America, see Mountain papaya. For the Eastern North American tree (and fruit) called "pawpaw", see Asimina triloba. For other uses, see Papaya (disambiguation).

Not to be confused with Chaenomeles speciosa (flowering quince) or Pseudocydonia chinensis (Chinese quince), which like Carica papaya are sometimes called mugua.

Papaya

Papaya tree and fruit, from Koehler's Medicinal-Plants (1887)
Scientific classification
Kingdom:	Plantae
(unranked):	Angiosperms
(unranked):	Eudicots
(unranked):	Rosids
Order:	Brassicales
Family:	Caricaceae
Genus:	Carica
Species:	C. papaya
Binomial name
*Carica papaya* L.

A papaya seedling.

Papaya output in 2005, shown as a percentage of the top producer, Brazil (1.7 megatonnes)

The papaya /pəˈpaɪə/ or /pəˈpɑːjə/ (from Carib via Spanish), papaw, or pawpaw is the fruit of the plant Carica papaya, the sole species in the genus Carica of the plant family Caricaceae. It is native to the tropics of the Americas, perhaps from southern Mexico and neighbouring Central America.^[1] It was first cultivated in Mexico^{[citation needed]}several centuries before the emergence of the Mesoamerican classical civilizations.
The papaya is a large, tree-like plant, with a single stem growing from 5 to 10 m (16 to 33 ft) tall, with spirally arranged leaves confined to the top of the trunk. The lower trunk is conspicuously scarred where leaves and fruit were borne. The leaves are large, 50–70 cm (20–28 in) in diameter, deeply palmately lobed, with seven lobes. Unusually for such large plants, the trees are dioecious. The tree is usually unbranched, unless lopped. The flowers are similar in shape to the flowers of the Plumeria, but are much smaller and wax-like. They appear on the axils of the leaves, maturing into large fruit - 15–45 cm (5.9–18 in) long and 10–30 cm (3.9–12 in) in diameter. The fruit is ripe when it feels soft (as soft as a ripe avocado or a bit softer) and its skin has attained an amber to orange hue.
Carica papaya was the first transgenic fruit tree to have its genome deciphered.^{[citation needed]}

Common names

Carica papaya plants and their fruits are known by different names around the English-speaking world:

North America and Belize: papayas
United Kingdom: The fruit is usually called papaya but is also known as papaw or pawpaw ^[2]
Africa: pawpaw or papaw ^[3]^[4]

Cultivation

Originally from southern Mexico (particularly Chiapas and Veracruz), Central America, and northern South America, the papaya is now cultivated in most tropical countries. In cultivation, it grows rapidly, fruiting within three years. It is, however, highly frost-sensitive, limiting its production to tropical lands.

Pests and diseases

This section requires expansion. (July 2011)

Main article: List of papaya diseases

Papayas are susceptible to the papaya ringspot virus (PRV), which causes premature molting and malformation of the leaves.^[5] In the 1990s, the virus threatened to wipe out Hawaii's papaya industry completely.
The papaya is also susceptible to the fruit fly, a small, wasp-like insect that lays its eggs in young fruit.

Cultivars

This section requires expansion. (July 2011)

Yellow flesh papayas, with decorative flowers

Papaya with red flesh

Two kinds of papayas are commonly grown. One has sweet, red (or orangish) flesh, and the other has yellow flesh; in Australia, these are called "red papaya" and "yellow papaw", respectively.^[6] Either kind, picked green, is called a "green papaya."
The large-fruited, red-fleshed 'Maradol', 'Sunrise', and 'Caribbean Red' papayas often sold in US markets are commonly grown in Mexico and Belize.^[7]
In 2011 Philippine researchers reported they by intergeneric hybridisation between carica papaya and Vasconcellea quercifolia they had developed conventionally bred, nongenetically engineered papaya that are proving resistant to PRV.^[8]

Genetically modified cultivars

In response to the PRV outbreak in Hawaii, genetically altered papaya were generated and brought to market (including 'SunUp' and 'Rainbow') that have some papaya ringspot virus (PRV) DNA incorporated into the DNA of the plant are resistant to PRVs.^[5]^[9] This was so successful that by 2010, 80% of Hawaiian papaya plants were genetically modified.^[10]^[11]

Uses

Papayas can be used as a food, a cooking aid and in traditional medicine. The stem and bark may be used in rope production.

Meat tenderizing

Both green papaya fruit and the tree's latex are rich in papain, a protease used for tenderizing meat and other proteins. Its ability to break down tough meat fibers was used for thousands of years by indigenous Americans. It is now included as a component in powdered meat tenderizers.

Nutrients, phytochemicals and culinary practices

Papayas, raw
Nutritional value per 100 g (3.5 oz)
Energy	179 kJ (43 kcal)
Carbohydrates	10.82 g
- Sugars	7.82 g
- Dietary fiber	1.7 g
Fat	0.26 g
Protein	0.47 g
Vitamin A equiv.	47 μg (6%)
- beta-carotene	274 μg (3%)
- lutein and zeaxanthin	89 μg
Thiamine (vit. B₁)	0.023 mg (2%)
Riboflavin (vit. B₂)	0.027 mg (2%)
Niacin (vit. B₃)	0.357 mg (2%)
Pantothenic acid (B₅)	0.191 mg (4%)
Vitamin B₆	0.038 mg (3%)
Folate (vit. B₉)	37 μg (9%)
Vitamin C	60.9 mg (73%)
Vitamin E	0.3 mg (2%)
Vitamin K	2.6 μg (2%)
Calcium	20 mg (2%)
Iron	0.25 mg (2%)
Magnesium	21 mg (6%)
Manganese	0.04 mg (2%)
Phosphorus	10 mg (1%)
Potassium	182 mg (4%)
Sodium	8 mg (1%)
Zinc	0.08 mg (1%)
Lycopene	1828 µg
Link to USDA Database entry Percentages are relative to US recommendations for adults. Source: USDA Nutrient Database

Papaya fruit is a rich source of nutrients such as provitamin A carotenoids, vitamin C, B vitamins, lycopene, dietary minerals and dietary fibre. Papaya skin, pulp and seeds also contain a variety of phytochemicals, including natural phenols. Danielone is a phytoalexin found in the papaya fruit. This compound showed high antifungal activity against Colletotrichum gloesporioides, a pathogenic fungus of papaya.^[12]

Ripe papaya fruits in tree

The ripe fruit of the papaya is usually eaten raw, without skin or seeds.
The unripe green fruit can be eaten cooked, usually in curries, salads, and stews. Green papaya is used in Southeast Asian cooking, both raw and cooked.^[13] In Thai cuisine, papaya is used to make Thai salads such as som tam and Thai curries such as kaeng som when still not fully ripe. In Indonesian cuisine, the unripe green fruits and young leaves are boiled for use as part of lalab salad, while the flower buds are sautéed and stir-fried with chillies and green tomatoes as Minahasan papaya flower vegetable dish. Papayas have a relatively high amount of pectin, which can be used to make jellies. The smell of ripe, fresh papaya flesh can strike some people as unpleasant.
The black seeds of the papaya are edible and have a sharp, spicy taste. They are sometimes ground and used as a substitute for black pepper.
In some parts of Asia, the young leaves of the papaya are steamed and eaten like spinach.
In some parts of the world, papaya leaves are made into tea as a treatment for malaria.^[14] Antimalarial and antiplasmodial activity has been noted in some preparations of the plant,^[14] but the mechanism is not understood and no treatment method based on these results has been scientifically proven.^[14]

Herbal medicine

Papaya is marketed in tablet form to remedy digestive problems.^{[citation needed]}
Papain is also applied topically in countries where it grows for the treatment of cuts, rashes, stings and burns.^{[citation needed]} Papain ointment is commonly made from fermented papaya flesh, and is applied as a gel-like paste. Harrison Ford was treated for a ruptured disc incurred during filming of Indiana Jones and the Temple of Doom by papain injections.^[15]
Women in India, Bangladesh, Pakistan, Sri Lanka, and other countries have long used green papaya as an herbal medicine for contraception and abortion.^{[citation needed]} Enslaved women in the West Indies were noted for consuming papaya to prevent pregnancies and thus preventing their children from being born into slavery.^[16]

Preliminary research

This section needs more medical references for verification or relies too heavily on primary sources. Please review the contents of the section and add the appropriate references if you can. Unsourced or poorly sourced material may be removed. (October 2012)

Preliminary medical research in animals has confirmed the potential contraceptive and abortifacient capability of papaya, and also found that papaya seeds have contraceptive effects in adult male langur monkeys, and possibly in adult male humans.^[17] Unripe papaya is especially effective in large amounts or high doses. Ripe papaya is not teratogenic and will not cause miscarriage in small amounts. Phytochemicals in papaya may suppress the effects of progesterone.^[18]
Other preliminary research indicates alternate possible effects which remain to be further studied. Papaya juice has an in vitro antiproliferative effect on liver cancer cells, possibly due to lycopene.^[19] or immune system stimulation.^[20] Papaya seeds might contain antibacterial properties against Escherichia coli, Staphylococcus aureus or Salmonella typhi.^[21] Papaya seed extract may have effects in toxicity-induced kidney failure.^[22]

Allergies and side effects

Unripe green papayas

Papaya is frequently used as a hair conditioner, but should be used in small amounts. Papaya releases a latex fluid when not quite ripe, which can cause irritation and provoke allergic reaction in some people.
The latex concentration of unripe papayas are speculated to cause uterine contractions, which may lead to a miscarriage. 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, the yellowing of soles and palms, which is otherwise harmless. However, a very large dose would need to be consumed; papaya contains about 6% of the level of beta carotene found in carrots (the most common cause of carotenemia).^[23]

Gallery

Female flowers of a papaya tree
Male flowers of a papaya tree
Leaf of a papaya tree
Papaya, Moche culture, Larco Museum Collection The Moche often depicted papayas in their ceramics.^[24]