Papaya (Carica papaya)

PAPAYA

Scientific name: Carica papaya L.

Synonym : 1. Papaya carica Gaertner,
2. Carica peltata Hook. & Arn.
3. Carica posoposa L.

Local Name : Betik

Common names according to respective countries:
Australia = Pawpaw
Chinese = Fan Mu Gua
English = Mamon, Papaya, Paw Paw, Pawpaw, Tree Melon
French = Papaye, Papayer
German = Melonenbaum, Papajabaum, Papajapflanze, Papaya, Papayabaum
Hindi = Papiitaa
Japanese = Papaiya, Papaya, Popoo
Korean = Pa Pa Ya
Malay = Betik, Gedang (Indonesia), Kates (Indonesian), Ketalah, Papaya (Indonesia)
Spanish = Fruta Bomba, Lechosa, Mamón, Melón Zapote, Olcoctón, Papanajo, Papayero,
Tamil = Pappali
Thai = Loko, Ma Kuai Thet, Malako, Malakor, Sa Kui Se

Family: Caricaceae

Introduction

Papaya is a sappy, soft-tissued, quick-growing but short-lived plant. It is believed to be native of tropical America, where it is called pawpaw as well as melon zapote. Spanish and Portuguese explorers brought papayas to many other subtropical lands to which they journeyed including India, the Philippines, and parts of Africa. It was believed that the Spanish had brought and introduced the papaya to Philippine and then afterwards to Malaysia.

Today papaya is widely grown in tropical countries situated between latitudes 32ºN and 32ºS. It has long been popular in tropical countries and also other parts of the world. The papaya is exported to Europe, Hong Kong, Singapore and Japan where it is in demand. The type of fruits in demand is one which is small in size, with orange to red flesh, sweet and juicy.

There are many local and introduced varieties of papaya in Malaysia. The introduced varieties incluides Cibinong and Paris from Indonesia; Sunrise Solo, Higgins and Wilder from Hawaii; Sunnybank from Queensland; Honeydew from India and Kokdum from Thailand. Most of the papaya varieties in Malaysia produced large and long sized fruits. Among the better know ones are the yellow-fleshed typed which includes Serdang, Honey Dew and Morib, while the red-fleshed kind includes Batu Arang, Subang 6 and Taiping 3. In Malaysia, papaya tree can be found growing around the house and also grown by local farmers as a commercial crop.

Papaya fruit is eaten fresh and is excellent in taste and othe nutritive quality. The flesh of papaya fruit is very rich in vitamin A, calcium and has also some vitamin C. The papayas are also processed into other preserved foodstuff such as pickled papaya, juice, nectar and puree.

Morphological Description and Biology of Papaya

Papaya is a short-lived perennial plant which may grow as tall as 9 m. Its hallow, herbaceous stem is usually unbranched, cylindrical with prominent leaf scars. The stem generally branches only when injured. All parts contain latex. The leaves emerge directly from the upper part of the stem in a spiral on a long and nearly horizontal petioles. The leaves are large, 50-70 cm diameter, deeply palmately lobed with 5 to 10 lobes and has a prominent yellowish ribs and veins. The life of a leaf is 4 to 6 months and will then die and fall as the tree grows. The papaya is a self-pollinated and cross-pollinated plant. Pollination is by insects and wind. The plant normally flowers in 9-12 months and ferilized fruits takes about 3-5 months to develop fully, depending on the variety.

Papaya flowers are fragrant and have five cream-white to yellow-orange petals, 2.5 to 5 cm long. Flower type is determined by the presence or absence of functional stamens (male parts) and stigma and ovary (females parts). Female flowers are relatively large, rounded at the base and have a stigma but lack stamens. They must receive pollen in order to set fruit. Male flowers are thin, tubular and usually borne on a long flower stalk (peduncle). They have perfect structure, that is they contain both male and female organs, but the small, vestigial ovary is non-functional. Hermaphrodite flowers are intermediate between female and male flowers in size and shape. They are less bulbous than female flowers, but not as thin as male flowers. Hermaphordite flowers have perfect structure with functional stigma and stamens.

There are three types of plants which can be recognized based on the flower type, which are female, male and hermaphordite plants. Female plants always produce female flowers. If no male or hermaphordite plants are nearby to provide pollen, female plants usually fail to set fruit. Unpollinated female plants occasionally set parthenocarpic fruits, lacking seeds. Female plants produces round fruits. Male plants are distinguished by their long flower stalks bearing many flowers. Usually they do not produce fruit, but on rare occasions there is female expression in the flowers, and they may set fruits. Hermaphrodite plants may have male flowers, hermaphrodite flowers, or both, depending on environmental conditions. Hot, dry weather may cause suppression of the ovary and the production of female-sterile (i.e., male) flowers. This accounts for occasional seasonal failure of hermaphrodite plants to set fruit. The hermaphrodite plant produces elongated and cylindrical fruits. These type of fruits are preferred due to its high quality and uniform shape and size.

Papaya is a non-seasonal plant and bears fruits throughout the year. The potential life span is about 25 years, but the productivity declines as the tree ages. A single tree may produce as much as 100 fruits and each fruit may weigh up to 2 to 3 kg. The fruit vary greatly in size, shape and flavour. The shape of the fruit is usually roughly oblong, blunt at the end or slightly pointed at the apex. The skin is smooth, thin and it ripens to yellow or orange color, or flushed with red. The flesh varies from creamy-yellow to a tomato red. The central part is hollow, with many winkled black seeds.

Anatomical Description

The leaf is dorsiventral, with well-developed intracellular spaces in the spongy tissue. Long, club-shaped, glandular hairs with multicellualr heads present on the petiole and along the principle veins. Stomata confined to the lower surface; ranunculaceous. Petiole, in transverse sections through the distal end, exhibiting a circle of numerous widely spaced collateral vascular bundles surrounding a very large, parenchymatous pith. Other strands, consisting wholly of phloem, also occur in the vascular ring interspersed between the colateral bundles. Articulated laticiferous canals accompany the vascular bundles of the veins and extend into the surrounding mesophyll. All parenchymatous tissues contain refractive grains of a substance in the nature of an aldehyde.

Glandular hairs, similar to those of the leaf, also present on the young internodes of the stem. Stem swollen at the base owing to dilation of the primary cortex and pith. Primary cortex largely composed of collenchyma. Pericycle including massive, isolated strands of fibers, in the form of caps to the well-developed, radially elongated groups of phloem. Secondary phloem stratified into hard and soft portions. Conducting system consisting of a circle of narrow, radially elongated vascular bundles, separated from one another by broad, parenchymatous rays. Ground tissue of the xylem composed of wadges of unlignified, parenchymatous tissue. Vessels mostly about 200 μ in radial diameter, solitary, or more frequently, radial multiples of up to 5 or more members. Lateral walls of the vessels with reticulate thickening and large, simple, gash-like pits where in contact with the parenchyma and almost circular intervascular pitting. Perforations were simple and horizontal. Wood fibers absent.

Taxonomy

Carica papaya is the cultivated papaya which belong to the family Caricaceae. Caricaceae is a small family of dicotyledonous plants with six genera. The genus Carica has only one species, which is C. papaya. A recently named genus Vasconcella were formerly assigned to the genus Carica. The genus Vasconcella has several species with edible fruits and these includes the mountain papaya, V. cundinamarcensis, V. pentagona, V. cauliflora and V. goudotiana. These species do not bear fruits with the succulence, taste and commercial value of Carica papaya. Some Vasconcella species have resistance to diseases to which C. papaya is susceptible, such as V. cauliflora 's resistance to distortion ringspot virus. Some attempts have been made to transfer resistance from wild to cultivated species, species but Carica papaya was not cross compatible with any of them. The table below shows the scientific classification of C. papaya or papaya.

Scientific Classification		Description
Kingdom	Plantae	Plants
Subkingdom	Tracheobionta	Vascular plants
Superdivision	Spermatophyta	Seed plants
Division	Magnoliophyta	Flowering plants
Class	Magnoliopsida	Dicotyledons
Subclass	Dilleniidae
Order	Violales
Family	Caricaceae	Papaya family
Genus	Carica	papaya
Species	Carica papaya	papaya

Chemical Constituents of Papaya

C. papaya contains many biologically active compounds. The two important compounds are chymopapain and papain, which are supposed to aid in digestion. The level of the compounds vary in the fruit, latex, leaves, and roots. The quantity of fresh papaya latex and dry latex (crude papain) also vary with the sex of the tree and the age of the tree. Female and hermaphrodite trees yield more crude papain than male trees and older fruit yields more than younger fruit. However, the activity of the papain is higher in the extracts from the younger fruit than the older fruit. The table below shows some of the compound found in parts of papaya.

Compounds	Concentration	Part of the plant
Alkaloids	1,300-4,000 ppm	leaves
Butanoic acid	1.2mg/kg	fruit pulp
Carpaine	1,000-1,500 ppm	Leaves. bark, roots, and seeds
chymopapain-a and b	-	latex and exudate
Flavonols	0-2,000 ppm	leaves
Papain	53,000 ppm	fruit and in latex and exudate
Tannins	5,000-6,000 ppm	leaves
Nicotine	-	-
Alpha-phellandrene	-	fruit
Alpha -terpinene	-	fruit
gamma-terpinene	-	fruit
4-terpineol	-	fruit
terpinolene	-	fruit
Linalool	94% of the volatile components in the fruit	fruit
Cis- and trans-linalool oxide	-	fruit
Alpha-linolenic acid	250-2,238 ppm	fruit

The papaya fruit contains about 88.8% water. Papayas also contain 16% more vitamin C than oranges and are a good source of vitamin A (about half of that contained in mango). The table below shows the nutritional value per 100 g of raw papaya.

Papaya, raw
Nutritional value per 100 g
…… … … .Energy 40 kcal 160 kJ … …
Carbohydrates	9.81 g
- Sugars	5.90 g
- Dietary fibre	1.8 g
Fat	0.14 g
Protein	0.61 g
Vitamin A	equiv. 55 μg	6%
β-carotene	276 μg	3%
Thiamin (Vit. B1)	0.04 mg	3%
Riboflavin (Vit. B2)	0.05 mg	3%
Niacin (Vit. B3)	0.338 mg	2%
Vitamin B6	0.1 mg	8%
Vitamin C	61.8 mg	103%
Calcium	24 mg	2%
Iron	0.10 mg	1%
Magnesium	10 mg	3%
Phosphorus	5 mg	1%
Potassium	257 mg	5%
Sodium	3 mg	0%

ETHNOBOTANICAL ASPECTS

Nutritional and health benefit of papaya

i) Papaya protects against heart disease

Papayas may prevent atherosclerosis and diabetic heart disease. It is an excellent source of three important antioxidant, which are vitamin C, vitamin E and vitamin A. These nutrients help prevent the oxidation of cholesterol. When cholesterol becomes oxidized, it is able to stick to and build up in blood vessel walls, forming dangerous plaques that will cause heart attacks or strokes. Papayas are also a good source of fiber, which helps to lower high cholesterol levels. The folic acid in papayas is needed for the conversion of homocysteine into benign amino acids. If homocysteine is inconverted, it can damage blood vessel walls, and may lead to heart attack or strokes.

ii) Papaya promotes digestive health

Papaya’s fiber is able to bind to cancer-causing toxin and keep them away from healthy colon cells. Other papaya’s nutrients such as folate, viitamin C, beta-carotene and vitamin E have been associated to reduce the risk of colon cancer. By eating papaya, it may increase the intake of these nutrients and therefore may reduce the risk of colon cancer.

iii) Papaya have an anti-inflammantory effects

Protein-digesting enzymes, such as papain and chymopapain in papaya, helps lower inflammation and improve healing from burns. The antioxidant nutrients found in papaya, including vitamin C, vitamin E, and beta-carotene, are also very good at reducing inflammation, such as asthma, osteoarthritis, and rheumatoid arthritis.

iv) Immune support

Papaya is a healty fruit choice for preventing illnesses such as recurrent ear infections, colds and flu, because vitamin C and vitamn A, which is made in the body from beta-carotene, are needed for the proper funcion of a healthy immune system.

v) Protection against Macular Degeneration

Fruits such as papaya is important for keeping your eye sight. Eating 3 or more serving of fruit per day may lower the risk of age-related macular degeneration (ARMD), which is the primary cause of vision loss in older adults.

vi) Protection against Rheumatoid Arthritis

Vitamins C-rich food, such as papaya, provide human with protection against inflammantory polyarthritis, a form of rheumatoid arthritis involving two or more joints. The findings from study, presented in the Annals of the Rheumatic Diseases, which involved more than 20,000 subjects, indicates that subjects who consumed the lowest amounts of vitamin C-rich foods were more than three times likely to develop arthritis than those who consumed the highest amounts.

vi) Papaya Prevent Prostate Cancer

Eating regularly lycopene-rich fruits, such as papaya may greatly reduce a man's risk of developing prostate cancer. This research finding was published in the Asia Pacific Journal of Clinical Nutrition, in an article wrote by Jian L. et al. (2007). Men who most frequently enjoyed these foods were 82% less likely to have prostate cancer compared to those consuming the least lycopene-rich foods.

Culinary uses

Papaya is usually eaten fully ripe when the flesh is soft and succulent. Ripe fruit can also be processed and used in a variety of products such as jams, fruit juices and ice cream. Papaya is an ingredient in a variety of cuisines throughout the world. The unripe green fruit of papaya can be eaten cooked, usually in curries, salads and stews. Green papaya is used in Thai cuisine, both raw and cooked. Unriped fruit can be eaten as raw, sliced into thin strips and eaten as vegetable or salad. The young leaves of papaya are steamed and eaten as ulam. The flowers are eaten in Java. The black seeds of papaya are edible and have a sharp, spicy taste. They are sometimes ground up and used as a substitute for black paper. Papaya seeds are also used as an ingredient in salad dressings.

The latex from unripe fruit and leaves contain a proteolytic enzyme papain. This enzyme can be used for tenderizing meat, clearing beer and for making chewing gum. Papain is included as a component in powdered meat tenderizers and also marketed in tablet form to remedy digestive problems. Processed products of papaya are not very popular and these include freeze-dried candy, leather, pickle, sauce, concentrate, drink, puree and pectin.

Uses in traditional medicine

The fruits, leaves, and latex are used medicinally. The enzyme papain is popular as a tropical application in the treatment of cuts, rashes, stings and burns. Women in many parts of the world such as in India and Pakistan have long used green papaya as a folk remedy for contraception and abortion. Medicinal research in animals has confirmed the contraceptive and abortifacient capability of papaya. Leaves poulticed onto nervous pains and elephantoid growths. The root infusion is used for syphilis in Africa and also to remove urine concretions. Flowers have been used for jaundice. Inner bark used for sore teeth. The enzyme papain is also used to treat arthritis.

The fruits of papaya has many benefits. According to the Malay culture, the latex is used to smoothen cracked heels. The leaves of papaya are boiled and the boiled water can be drink to lower the body temperature from fever and to treat malaria. The mature ripe fruit is used to treat ringworm, while green fruit can be use to treat high blood pressure and also used as an aphrodisiac. The fruit can be directly applied to skin sores and its juice which contain enzymes within it are used to reduce gastrointestinal gas and especially useful to sufferes of irritable bowel syndrome (IBS). The seeds are anti-inflammatory, anthelmintic, and analgesic, and they are used to treat stomachache and fungal infections. The leaves are used as a heart tonic, analgesic, and to treat stomachache. The root of papaya tree are used as an analgesic.

The following table shows aliments in humans that is treated using papaya in different countries of the world.

Aliments	Country
· Abortifacient - Causing abortion	Java, Panama, Sri Lanka, and Turkey
· Arthritis - Inflammation of a joint or joints resulting in pain and swelling. · Rheumatism - Any of several pathological conditions of the muscles tendons joints bones or nerves characterized by discomfort and disability	Haiti and Jav
· Asthma and respiration	Mauritius, Mexico, and Philippines
· Bactericide - An agent that destroys bacteria	India
· Cancer	Australia and Mexico
· Constipation - infrequent evacuation of dry hardened feces from the bowels. · Laxative - A food or drug that stimulates evacuation of the bowels.	Honduras, Panama, and Trinidad
· Diarrhea · Dysentery - An inflammatory disorder of the lower intestinal tract usually caused by a bacterial parasitic or protozoan infection and resulting in pain fever and severe diarrhea often accompanied by the passage of blood and mucus	Honduras, Japan, Panama, and West Africa
· Diuretic, flu, scorpion bites	Trinidad
· Dyspepsia - indigestion · Tuberculosis - Tuberculosis of the lungs characterized by the coughing up of mucus and sputum fever weight loss and chest pain	Mexico
· Dysuria - Painful or difficult urination	Java
· Fever	Java and Mexico
· Hypertension	Honduras and Trinidad
· Intestinal disorders	Philippines
· Madness	Ivory Coast
· Milk production (increase/stimulate)	Indonesia and Malaysia
· Ophthalmology treatment, Urology treatments	Soviet Union
· Toothhache	Cote d'Ivoire and Samoa
· Tumor (Uterus)	Ghana, Indochina and Nigeria
· Ulcer	Panama
· Venereal disease - a disease that is spread through sexual activity with an infected person; a sexually transmitted disease	Trinidad
· Vermifuge - A medicine that expels intestinal worms	Haiti, Malaya, Panama, Samoa, and Turkey
· Warts	Indonesia, Jamaica, Peru, South Africa, and Sri Lanka

Other uses

The latex from papaya can be used to remove freckles. The bark of papaya tree is used for making rope. The leaves are used as a soap substitute and are supposed to remove stains. Papain, the proteolitic enzyme has a wealth of industrial uses. The papain is used for meat-tenderizers, making chewing gums and also used to extract the oil from tuna liver. Cosmetically it is used in some dentifrices, soaps, shampoos, lotions, creams and face-lifting preparations. In pharmaceutics, the papain is used for suppression of wound inflammation and as a laxative. Papain is also used in the textile and tanning industries. The culled fruits can be fed to pigs and cattle.

The papaya industry

The global production of papaya in 2003 were more than 6 million matric tonne. The most important papaya exporter in 2002 were Mexico (32.1%), Malaysia (28.5%), Brazil (13.4%), Belize (5.3%) and Hawaii, USA (3.3%). The most important papaya importer in 2002 were USA (44.9%), followed by Singapore (13%) and then China (12.7%). The major supplier for China and Singapore is Malaysia. For the domestic trade, the local demand for papaya had been increasing since 1996. the total demand had increased by 54% from 57,430 mt in 1996 to 88,200 mt in 2003. households are the largest consumer in 2003, which comprises of 60% of the total consumption. A retail market price is RM 1.20 per 1 kg, and the local papaya market was valued at RM 106 million in 2003. The major export destination for Malaysia’s papaya in 2003 was Hong Kong, which accounted for 80.4% of the total papaya export value, followed by Singapore, United Arab Emirates and Brunei. The export value of fresh papaya in 2003 was estimated at RM 100.8 million. Papaya fruits are marketed locally through direct sales to consumers through Pasar Tani operated by FAMA, sales to wholesale markets, direct sales to hypermarket and supermarkets, sales through contract farming, direct sales to retails, experters, households consumers and hotels and local institutions.

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