Sea cucumber protein used to inhibit development of malaria parasite

Scientists have genetically engineered a mosquito to release a sea-cucumber protein into its gut which impairs the development of malaria parasites, according to research out today (21 December) in PLoS Pathogens. Researchers say this development is a step towards developing future methods of preventing the transmission of malaria.
Malaria is caused by parasites whose lives begin in the bodies of mosquitoes. When mosquitoes feed on the blood of an infected human, the malaria parasites undergo complex development in the insect’s gut. The new study has focused on disrupting this growth and development with a lethal protein, CEL-III, found in sea cucumbers, to prevent the mosquito from passing on the parasite.
Human blood infected with malaria contains parasitic gametocytes – cells which can create parasite sperm and eggs in the gut of the insect. These then fertilise, kick-starting the parasite reproductive process and life cycle by producing invasive offspring called ookinetes.
These ookinetes then migrate through the mosquito’s stomach wall and produce thousands of ‘daughter’ cells known as sporozoites. After 10-20 days these are ready in the salivary glands to infect another human when the mosquito takes a subsequent blood meal.
The international team fused part of the sea cucumber lectin gene with part of a mosquito gene so that the mosquito would release lectin into its gut during feeding. The released lectin is toxic to the ookinete and therefore kills the parasite in the mosquito’s stomach.
In laboratory tests the research team showed that introducing lectin to the mosquito’s gut in this way significantly impaired the development of malaria parasites inside the mosquito, potentially preventing transmission to other people. Early indications suggest that this sea cucumber protein could be effective on more than one of the four different parasites that can cause malaria in humans.
Professor Bob Sinden from Imperial College London’s Department of Life Sciences, one of the authors on the paper said: “These results are very promising and show that genetically engineering mosquitoes in this way has a clear impact on the parasites’ ability to multiply inside the mosquito host.”
However, Professor Sinden explains that there is still a lot of work to do before such techniques can be used to combat the spread of malaria in real-world scenario. This is because although the sea cucumber protein significantly reduces the number of parasites in mosquitoes, it does not totally remove all parasites from all mosquitoes and as such, at this stage of development, would not be effective enough to prevent transmission of malaria to humans.
Professor Sinden says he hopes studies such as this one, which improve scientists’ understanding of the complex process by which malaria parasites are transmitted, will lead to new advances in the quest to prevent malaria.
“Ultimately, one aim of our field is to find a way of genetically engineering mosquitoes so that the malaria parasite cannot develop inside them. This study is one more step along the road towards achieving that goal, not least because it has been shown that more than one species of malaria can be killed in this way.”
About 40% of the world’s population are at risk of malaria. Of these 2.5 billion people at risk, more than 500 million become severely ill with malaria every year and more than 1 million die from the effects of the disease. Malaria is especially a serious problem in Africa, where one in every five childhood deaths is due to the effects of the disease. An African child has on average between 1.6 and 5.4 episodes of malaria fever each year.
Source : Imperial College London

Tropical Fruits

Mango East Java has earned the reputation of being the nation's fruit bowl. It is particularly known for its apples and mangoes which are now being exported if there is an abundant yield. Mangoes, however, are very popular fruit and this counts for the whole nation. Topping the list of a great variety here is the famous Mangga Arum Manis which grows very well on East Java soil. Whole areas around Probolinggo, Pasuruan, have been converted into mango plantations. When in season which falls mostly in the hottest and driest period of the year, Arum Manis is transported by trainload to destinations scattered over the entire island of Java. But the bulk is still going to the capital, Jakarta, which, with a population of more than 8 million is still the largest consumer. Arum Manis is a darkgreen mango even when ripe. Its flesh is at times lemon and in another variety deep orange. The Arum Manis flavor, however, is unmistakable in charac ter which another mango type has not been able to equal yet. Its sweetness borders on nectar sometimes without a cloying after taste. There are three popular mango varieties in this country. The much sought after Arum Manis, Manalagi and Golek. Manalagi is a newer mango kind also of a very sweet flavor. It is only somewhat smaller than the two other types. Golek is the largest mango variety whose sweetness does not come up to par with that of Arum Manis and Manalagi. Even so, the fruit is economically a winner because of its fleshy contents. Although the mango has been around for centuries in this country, the fruit was originally from India. From tales still alive to this day, one may safely assume that the fruit made its entree during the Hindu period in this country. The legend about the mango in the region of Pasuruan was undoubtedly born in those days, a tale persisting in the belief that the fruit is a reincarnation of the deity P rajapati. Improvement in the local horticultural techniques benefited the East Java fruit growers who saw their crop yields growing each year. 1983 went down in the annals of the Regional Government as a lucky year for mango export. Most of the fruit export is destined for Singapore which distribute it again to other places on the globe. One of the stumbling blocks in the tropical fruit export is packaging. Tropical fruit especially needs careful packing since many fruit varieties spoil and bruise easily. Mangoes of a lesser type are legion in the country. Some of the names are, Egg Mango (mangga telur), Mango Indramayu, Mango Kwini, too many to be named here. The most dominating feature of these mangoes are that its flesh incorporates a network of fibrous strings which are in the habit of getting stuck in between one's teeth. These mangoes are also quite cheaper. One type, known as Mango Kwini in the province of North Sulawesi, and the southern part of the province of North Sumatera spreads a penetrating and stifling odor when it is ripe. The kind almost always gives itself away in households who have a few in stock. Apart from the apalling odor it emits, Mango Kwini's flavor is actually quite pleasant to the taste. The fruit is rather large and round of shape. The skin is of a dirty green speckled with black spots. The fruit grows on all islands of the archipelago. The Egg Mango is an attractive looking fruit. When it is ripe, the fruit turns bright orange. The Egg Mango, so called because of its shape like an egg, is smallish in shape. It is one of the most reasonable priced mangoes everywhere in the land. Apples (Males Sylvestris) Apples in Indonesia Apples are grown in this part of the world, indeed. To be more precise, they are grown in East Java in the mountain region of Malang and Batu. The first apple tree sprouted up decades ago when a Dutchman with a green thumb tried to grow a four-season plant in a wholly different climate and on different soil too. Malang see-me to have the right temperature for apple growing. Situated on a level of 700-800 meter above sea surface, the first trees were doing surprisingly well despite the tropical climate. There was a large difference though between the European apple and his Malang grown sister, which became all too apparent when the first fruits were reaped. The apples were reportedly too sour for consumption. For a while people in Malang regarded the apple tree as a decorative shrub to have in the garden. The fruits went to waste usually as they were soon declared as quite inedible fruit. In several instances reports repeated that apple trees in other parts of the region were not even bearing fruits at all. After world war 11 and after the country gained independence from the Dutch more people became interested in apple cultivation. Growth expanded considerably compared with the few and far in between shrubs from before the war. But the Malang apple remained a very unpopular fruit among Indonesians who clamored more for the imported stuff which was sweet and juicy. In time apple farmers were introduced to newer agricultural techniques which transformed the sour Malang apple into a fruit of refreshing taste and of a crunchy consistency. The people of Malang and thereabouts were plain delighted. Soon more apple orchardes were started, not only in Malang. The village of Batu followed suit and the uplands of Pasuruan, Mojokerto, Probolinggo, Ponorogo, Nganjuk, Magetan and further away, Madiun. Malang still produces the largest yield with an annual crop of averagely 203.000 ton. A ministerial decree banning the import of foreign fruits that was issued in the early ens, reportedly drove up the apple crop in East Java. Apples from East Java are now in great demand with juice producents, bakeries, and everyday people since the homegrown fruits bear reasonable pricetags. With local apple consumption ever on the upswing, present crop yields are never enough to boost the country's export figures of local apples. Avocado (Persea Americana Milll) Avocado, once a fruit that came hardly to the attention of the local people because of its availability to anybody, ranks now in an exalted state because of its multitudal value to the sophisticated tongue and those of simpler tastes. Avocado in international cuisine whose following is growing rapidly among affluent Indonesian householders, has elevated this once lowly fruit to its present levels. Before international lunching and dining became a natural activity as it is today, the avocado was merely regarded as a cheap but nice fruit to make juice from. In the Minahasa, North Sulawesi, where the majority of the population is of Christian faith, more abuse is inflicted on this easily grown fruit with many possibilities. Pig farmers were known to feed avocado to their fare since the fruit never fetched a price worth mentioning on the market. Trees were not actually planted then. They happened to be there by nature. Avocado nowadays are specially raised for export in East Java. The bulk of the crop is reportedly destined for Singapore. Citrus Varieties (Citrus Reticulata Blanco) A great variety of the citrus family is represented in East Java and to a lesser degree, also West Java. Called 'jeruk keprok', meaning in the region's jargon "bashed in lemon,. this type of mandarin with crumpled skin has been a household word in East Java since centuries, perhaps. These mandarins are a very close image of the Chinese mandarins on sale in Hong Kong at around Chinese New Year. One can only assume their place of origin since research in this field is at the moment non-existent. The East Java Mandarin, though, has now undergone several crossing which has improved its outer ooks. Instead of the puckered, crumpled skin, the fruit now appears to sport a smooth satin like peel that no longer turns orange when the fruit ripens on the tree. Instead, the skin retains its luscious green color right through the ripening process. Beside the mandarin, there is "Jeruk mania", a relative of the Spanish orange of the same flavor, but less sweet. It is in season together with the mandarins when real hot weather when its juice colors most drinks in eating establishments. In West Java this variety has a sister going by the name 'jeruk Garut' (orange from Garut). Garut is a small place in the highlands of West Java which grows several citrus varieties, among others this green orange. Unlike the imported oranges, the Garut orange remains freshly green on the outside and so do several other citrus kinds in Indonesia. The lemon family in this country follows an interesting line. On top is the 'jeruk nipis', a close relative of the western lemon which is three times larger in size and colored pale lemon. The local lemon is a very round citrus kind whose skin does not undergo any change in the ripening process. The difference in outer looks notwithstanding, its flavor is the same as that of the western lemon. One citrus kind which is of medicinal value, and quite unfit for consumption, is a pear shaped lemon with a rough un-smooth skin going by the name of 'lemon suangi'. The fruit is used to ward off the "evil eye" in the northern region of the island Sulawesi. Its leaves often become the main ingredient in a traditional potion that is supposed to heal all kinds of ailments. The medicine is doing wonders with tummy problems. This lemon variety, however, is now on the list of endangered plants because of excessive use by the local populating in isolated places of the island. It is said that the'lemon suangi' used to grow in the wilds. Nobody really cultivated the plant. It had always been there when it was needed by medicine men. Now, the Lemon suangi' has become a rare fruit which is not easy to find. Another type in the same citrus family found only in the most northern area of Sulawesi, is really a teeny-weepy orange, the'lemon chui'. Thorny Fruit (Dunio Zibethinus Murr) Some of the tropical fruit varieties are shielded by a thorny skin. In this range come Durian (Durio Zibethinus Murr), Jackfruit and to some extent, Soursop. Of the three the thorns of Durian are sharpest. To get to the contents of this fruit one has to have an adroitness for opening the fruit. Durian is not skinned like other fruits. It is squeezed open by way of putting pressure upon the whole fruit. The durian will easily fall apart in segments of four to five when the fruit is ripe. Controversy surrounds the Durian heavily whose unpleasant outer appearance only helps making matters worse. The pro's and contra's for durian are more in favor for the first group in this country where the majority of the population regard it as the king of all fruits. Newcomers from non-tropical countries usually react strongly at first encounter with the fruit as they try to grapple with the appalling odor emitted by the durian. There is no way to exactly define the durian aroma. Some people take it rather well, still others may take offense from the odor which is of a persistent and penetrating quality. Of the taste, some newcomers liken it as something coming close to heaven, Others commented on it briefly with a four-letter word. Europeans who came to like the fruit say that one has to aquire a taste for durian. At first the fleshy seed may not reach much further before the throat. Normally, it would take several trials before the taste for the fruit is finally established. Jackfruit (Arthocarpus Heterophyllus Syn. Artocarpus Integra) Another fruit, a real giant in size, also has a thorny appearance. The thorns are not too sharp as that of the durian though. Nangka, or in English, Jackfruit, is a seasonal fruit. The seeds enclosed in yellow meat, are a great delicacy for most people. jackfruit is also a local vegetable before the fruit ripens. It then becomes the main ingredient in a vegetable dish made with coconut milk called 'gudeg'. Un like Durian, Jackfruit emits a pleasant aroma when ripe. It's meat is of a golden color and quite sweet. Soursop (Annona Muricata) The last in the thorny fruit variety is Soursop (Anona Muricata L.), so called because of its immensely sour taste. Strange as it may sound, the fruit is in the habit of attracting black ants of the variety found to penetrate closed bowls of sugar. Soursop has to be prepared with sugar or sweeteners when it becomes a very refreshing fruit drink. Unlike the thorns of Durian and Jackfruit, the soursop's skin is a pliable covering scattered overed with soft thorns. Soursop fruit is now cultivated in large quantities for the supply of fruit juice manufacturing. Soursop is an easy fruit to cultivate because the tree does not require special soil. It is able to grow in coastal areas and also on higher ground unlike Jackfruit which is doing better on higher levels of about 700 metre. Snake Fruit (Salacca edulis Reeinw) Locally known as Salak (Salacca edulis Reinw) the skin of this fruit is a deead look a like of snake skin. Snake fruit is a dead look relative of the palmtree, but the kind that stays close to the ground. The fruit nestles in clusters a little above the root of the tree on a bed of long, thin thorns. Except for the thorns on the main nerves of the leaves, the tree is often mistaken for the sago palm. Salak palms thrive best on dry, sandy, soil. The fruit has a swet acid like flavor and is totally dry. Juice of snake fruit is entirely non-existent. The best snake fruit in the country is cultivated on the island of Bali. Bali Salak is the sweetest of all snake fruit with only a slight trace of acid on the tongue. The season of Salak is near the end of the year, or, at the start of a new year. Pineapple (Ananas Comosut) Another fruit available throughout the year is Ananas (Ananas comasut (L) Merr.) or pineapple. The pineapple tree is an agave like plant with pink leaves which grows without difficulty on all the islands of the archipelago. Before only grown for consumption in the country, Ananas growth has manifolded since the making of canned fruit was introduced in the country. Now there is fresh Ananas as well as canned pineapple available which is mostly earmarked for export. The best of this fruit is grown in Palembang on Sumatra which has earned the reputation back in colonial days. The Palembang pineapple is nothing much to look at. It is small compared with others grown in other parts of the country with a scrawny look about it. But its content is very rich in juice and glucose. The taste of Ananas from Palembang is just like sheer nectar and honey which cannot be said of other pineapple varieties here. Some pineapple are, despite the luscious golden color, of a sourness for which there is simply no word in existence. Technology brought more than agricultural knowledge. It added industrial know how to pine-apple planters who discovered that pineapple leaves is not only a basic ingredient in cable manufacturing. Fibers of the leaves also make good ground material for cloth, although this kind of cloth has not been developed yet to the full as in the Philippines. At present it is more looked upon as an unusual novelty. Other preservation technique besides pineapple canning is converting Ananas into pineapple jam. This fruit jam is very popular with the majority of the people. Not only is it made as a spread on bread, it is also used as a filling in small butter pies known in the country's jargon as 'nastar.'Ananas jam used to be a homemade product. In our mothers' and grandmothers' days, housewifes pride themselves with having the best recipe for pineapple jam. Pineapple jam bubbling on the stove emits a tantalizingly pleasant aroma of the fruit with cinnamon and a few dried cloves which reaches all the rooms and carners in the house. Nowadays, pineapple jam is mostly a mass product prepared and bottled in factories, sprouting with unbelievable speed in industrial areas of the country. Rambutan and Dukuh (Nephellium Lapaceum L. and Lansium domesticum Corr) Two fruit varieties that will always be winners with the fruit loving people of Indonesia, are Rambutan and Dukuh when they are in season. The season of Rambutan follows closely after the Durian season, and almost simultaneously with that of Dukuh. Rambutan is a special fruit, in that, it is a fruit covered with a hairy peel in red and pink colors. Its fleshy seed is white and sweet. It should be noted that of all tropical fruit Rambutan has won over many non-tropical fruit consumers because of its exotic flavor and unusual appearance. This fruit has become a most sought after delicacy among the Japanese who are reportedly, going in a big way for exotic fruit which they import from the States. Next to Japan, the United States have squired a taste for tropical fruit. So much so, that tropical vegetable gardens and orchards were started to satisfy growing demands. According to writers' stories, in California one can get all the tropical fruit and veg one could wish for. Henceforth, rambutan will be available when the season arrives. In Indonesia, the rambutan cultivations has received a boost with the oncoming of the canning industry more than a decade ago. Superfluous Rambutan do not rot away like before. The fruit is being directed to such factories where they will be conserved in syrup prior to canning. Dukuh, or Lansa in East Indonesia, is a round fruit with yellowish skin that sometimes show dirty spots on them. The variety of East Indonesia, Lansa, has a much more clearer skin of a spotless golden color, There is obviously a difference between the two which is hardly noticable. Dukuh is perfectly round and Lansa is of an oval shape. With regard to taste, many share the opinion that Dukuh is much sweeter than Lansa. In spite of the fruit's popularity, many people refrain from eating too much of it because Dukuh juice has been found to cause an irritating throat. One doctor said that together with Dukuh time, sore throats and coughs are also sharply increased. Health buffs have wondered a long time about this coincidence until they stumbled upon the above finding about Dukuh and Lansa juice. The fruit, when in season, is sold in clusters like grapes along particular roadsides and in traditional markets. Jambu Air (Sizygium Aquem Merr & L.M. Perry) A very pretty fruit is Jambu Air which comes in three colors. Red, white and pink. Before a Jambu Air tree starts to bear fruit, pink blossoms all but cover the whole crown of the tree. A few of Jambu Air trees in bloom will spread a dainty fragrance in the garden. Jambu Air grows quickly and easily. Once the seedling has sprouted roots it would need very little attention except for watering the plant regularly. Jambu Air is a very juicy fruit, though it is not exactly sweet or sour. The white variety which is less mushy is found to be sweeter than its colored sisters. Jambu air is used in local salad, "Rujak." Mangosteen (Garcinia Mangostana) The mangosteen grows under the dense foliage of a medium-size tree and is quite .hard to see unless one is directly berieath it. One tree does not produce more than a few ripe fruits at a time and the tree is hard to propagate. There are thus no mangosteen plantations. The card-red husk encloses six or seven symmetrical segments. Splitting the rind is tricky because it is hard and tends to crumble, but one open, the segments separate easily. There is often considerable variation in the degree of maturity of each segment. The larger, mature segments usually have a seed while the others have an embryonic seed so small and soft it may go unnoticed. The taste is delicate, subtle and deliciously sweet. Mangosteens are easily found in the markets and fruit stalls starting in September. Hotels serve them regularly, usually in a mixed fruit basket. Sapodilla (Sapota Zaspotilla) Sapodilla grows on a small, unpretentious tree found all over the archipelagoes. The fruit looks like a small, brown potato with smooth skin. The flesh is a rich brown color with a vague radial structure of a lighter color, and contains one to five large seeds. The sapodilla has a very sweet, sugary taste, which hints at maple sugar. It is soft, though not juicy. The texture is very slightly gritty, but not obiectionably so. The fruit can be broken open and the flesh easily eaten without consuming, either the seeds or the skin. Sapodilla must be eaten ripe, however, because the fruit contains tannin and a milky latex when unripe. Pomegranate (Punica Granatum) The pomegranate is a native of the Middle East but was cultivated in India and Indonesia already in ancient times.lt grows on a large shrub or small tree which has brilliant orange-reddish flowers. About the size of an orange, the dullred pomegranate has a tough, leathery skin which allows the fruit to travel well. The skin encases six paper-thin sepsums, each containing seeds that are individually encased within a transparent, pulpy capsule. The fruit and the rind are an effective anti-bacterial agent, and the dried rind isoften used as a relief for dysentery. Starfruit (Averrhoa Carambola) Starfruit grows abundantly on a small tree that is found just about everywhere in the low and medium elevations of Indonesia. The fruit has not been highly bred so there are a number of local varieties, differing in size and sweetness. Only a fraction of the fruit finds its way to the local markets. The translucent skin of the golden-yellow fruit is so thin it can be easily punctured by a fingernail. The crisp and juicy pulp is fragrant and has a tart taste. The fruit is firm when ripe and can be eaten raw-skin and all-once the tough edges of the five ridges are peeled off. Despite the slightly acidic taste, starfruit does not contain tannin and so is not astringent. The tree and the fruit are considered to have uses varying from removing cloth stains to curing hangovers, and it is very high in vitamin C

Banana

The true origin of Bananas, world's most popular fruit, is found in the region of Malaysia. By way of curious visitors, bananas traveled from there to India where they are mentioned in the Buddhist Pali writings dating back to the 6th century BCE. In his campaign in India in 327 BCE, Alexander the Great relished his first taste of the banana, an usual fruit he saw growing on tall trees. He is even credited with bringing the banana from India to the Western world. According to Chinese historian Yang Fu, China was tending plantations of bananas in 200 CE. These bananas grew only in the southern region of China and were considered exotic, rare fruits that never became popular with the Chinese masses until the 20th century.

Eventually, this tropical fruit reached Madagascar, an island off the southeastern coast of Africa. Beginning in 650 CE Islamic warriors traveled into Africa and were actively engaged in the slave trade. Along with the thriving business in slave trading, the Arabs were successful in trading ivory along with abundant crops of bananas. Through their numerous travels westward via the slave trade, bananas eventually reached Guinea, a small area along the West Coast of Africa. By 1402 Portuguese sailors discovered the luscious tropical fruit in their travels to the African continent and populated the Canary lslands with their first banana plantations. Continuing the banana's travels westward, the rootstocks were packed onto a ship under the charge of Tomas de Berlanga, a Portuguese Franciscan monk who brought them to the Caribbean island of Santo Domingo from the Canary Islands in the year 1516. It wasn't long before the banana became popular throughout the Caribbean as well as Central America. Arabian slave traders are credited with giving the banana its popular name. The bananas that were growing in Africa as well as Southeast Asia were not the eight-to-twelve-inch giants that have become familiar in the U.S. supermarkets today. They were small, about as long as a man's finger. Ergo the name banan, Arabic for finger. The Spaniards, who saw a similarity to the plane tree that grows in Spain, gave the plantain its Spanish name, platano.

It was almost three hundred and fifty years later that Americans tasted the first bananas to arrive in their country. Wrapped in tin foil, bananas were sold for 10 cents each at a celebration held in Pennsylvania in 1876 to commemorate the hundredth anniversary of the Declaration of Independence. Instructions on how to eat a banana appeared in the Domestic Cyclopaedia of Practical Information and read as follows: "Bananas are eaten raw, either alone or cut in slices with sugar and cream, or wine and orange juice. They are also roasted, fried or boiled, and are made into fritters, preserves, and marmalades."

Note: The banana plant is not a tree. It is actually the world's largest herb!

Papayas

Papaya, Pawpaw (Great Britain, South Africa), tree melon, ketela, kepaya ma-la-ko (Thai), pappali (Tamil)
(Carica papaya -- Family Caricaceae)

The name "pawpaw" should not to be confused with the fruit of the same name from the Annona family, which is related to the Cherimoya and custard apple.

In Australia and New Zealand, papaya (C. papaya) is called "paw paw", while the paw paw (Asimina tribola -- Family Annonaceae -- see below) found in North America is not related to the papaya. The only thing the two have in common is that both can be used for medicinal purposes. At least eight other species of the genus Carica, including babaco, bear edible fruits. The mountain papaya of the Andes, C. candamarcensis, is always cooked because of its high papain content.

Papaya is a fruit native to eastern Central America and was cultivated long before the arrival of the Europeans. Spanish and Portuguese invaders took to the fruit and quickly spread it to their other settlements. It was found growing in the West Indies by 1513; and, by 1583, it found its way to the East Indies via the Philippines. It had also made its way into Africa at an equally early date, and spread through the Pacific islands as Europeans discovered it. By 1800, papaya was grown in all tropical regions, with Hawaii and South Africa now the main exporters.

The papaya plant is a large herb that grows rapidly, reaching heights of more than twenty-five feet and producing a soft wood. The huge fingered leaves form a spiral similar to those of the palm tree. The plant grows quickly from seed and bears fruit within a year, continuing to do so for another two years before the tree is cut down. The tree grows best in temperatures of 25°C (77°F) and does not like storms or winds. It also requires good drainage as the roots will rot if they become water-logged. Frost also kills the tree. It does grow well in containers, making it an ideal house plant that can be put outside in the spring as soon as the fear of frost is past. Such strains as Hortus Gold of South Africa have separate male and female trees. Seedlings are planted in threes, and the males are used only for pollination and then discarded once the sex of the trees have been established and pollination has been accomplished. Others, such as the Hawaiian Solo, have fruiting hermaphrodites, which are preferred, and the females are later thinned out. These two strains produce the majority of the papayas in the West.

The fruits hang in large clusters along a central stem from the top down. Elongated watermelon-size papayas are not uncommon in Mexico, Asia, Puerto Rico and other Caribbean countries, weighing ten pounds or more; but those sold commercially are rarely more than six to eight inches in length and weighing about a pound. Some varieties remain green when ripe, but most have skins that turn a deep yellow or orange. The flesh of the papaya may be yellow or a beautiful deep, salmon-pink colour. No matter what the colour though, all will have an abundance of black seeds in the central cavity. The seeds are edible and highly nutritious; but they have a very spicy, peppery flavour. These are often ground up for medicinal purposes. The soft, juicy sweet flesh tastes like a cross between melons and peaches. The skin and the flesh are both edible and can be served the same way as melons, either eaten alone or in combination with other fruits. The leaves are also used for medicinal purposes, and sprouts can be gathered for salads after they reach a height of about twelve inches. For medicinal purposes, fresh leaves are more valuable and nutrient-rich than the fruit.

Papayas are an excellent fruit for antioxidants, containing not only vitamin E, but also more vitamin A than carrots and more vitamin C than oranges. It is also an excellent source of calcium, potassium, iron, B vitamins, and proteins. Along with these nutrients, it is the papain that most people are familiar with in this fruit. Papain assists in chemically transforming proteins into various amino acids, including arginine which influences the human growth hormone to increase muscle tone and decrease body fat. This enzyme is able to digest thirty-five times more protein than its own weight. Scientists consider papain to be a more powerful protein-digesting enzyme than either the body's own pepsin or pancreatin, which become inactive if the stomach acid is low. Papain, on the other hand, remains active whether it is in an acidic, alkaline, or neutral environment. At the same time, research has shown that papain can be effective in fighting cancer as it breaks down a protein substance called fibrin, found on all cancer cells, and thus preventing metastasis, including inhibiting the growth of human breast cancer cells. Patients taking papaya enzymes have shown to recover faster from surgery, radiation, and chemotherapy.

However, what most people do not realize is just where this valuable enzyme is located. Almost no papain is found in fully ripe fruit, but there is an abundance found in the leaves and green fruit. In addition, papain varies considerably with the species. Similar to papain, papaya also contains another enzyme, myrosin, and an alkaloid, carpaine, which calms the heart, bronchus, and muscles. Blending green fruit, a few seeds, pulp, skin and all in a drink is one way to dramatically increase nutrients, as well as benefit from the vital digestive enzymes. Mature green papaya also contains another enzyme which works along with papain to digest carbohydrates and fats. It also possesses an antiseptic quality that helps prevent an overgrowth of undesirable intestinal bacteria and parasites. Although the green fruit is not as palatable as the ripe, it does have only about two-thirds the carbohydrates of ripe fruit and twice as much digestible protein. However, it does contain less vitamin A.

The skin of the fruit is considered to be the most potent part to be used for medicinal purposes. It is well advised to use only organically grown papaya as the chemicals used during its growth are not conducive toward any health-promoting purposes. About one-quarter of the seed consists of a highly digestible protein which can be ground up and used to eliminate intestinal parasites. Even though the seeds are soft enough to chew, they are very spicy and must be ground up and mixed with something or swallowed quickly with juice, if taking many of them for this purpose. It takes about twenty seeds for about five days to eliminate most any intestinal parasite effectively. Papaya also effectively detoxifies the body, speeds metabolic processes, and increases elimination of toxins. Restoring enzymes to the body puts less strain on internal organs and strengthens the immune system. It also converts the amino acid arginine, which is an essential amino acid that influences proper cell function.

In 1875, a British physician, T. P. Lucas, discovered the medicinal value of papaya and started a hospital in Brisbane, Australia, to treat patients solely with papaya. The people in Papua New Guinea use papaya for the skin and to treat rashes or sunburn or, with repeated applications, to remove the brown spots of aging. They also say that if you put papaya into the compost pile, they grow especially large! Natives in the Pacific Islands use all parts of the papaya tree for medicinal purposes -- leaves; skin; seeds; bark; roots; flowers; and, of course, the fruit. South American women massage their breasts with thin slices of green papaya to stimulate the milk glands. Eating the fruit provides energy and nutrients for both herself and the baby. Papaya bark is used as a toothache remedy and the flowers in teas, to treat bronchial infections. For centuries, teas made from the roots were used to expel parasites and to alleviate bleeding, kidney colic, and jaundice.

Papaw, pawpaw (Asimina triloba -- Family Annonaceae) is the fruit of a small North American tree that can be found as far north as New York State, and has for a long time been cultivated by Native Americans. Its name is also used for a type of papaya, which is a completely different fruit. The papaw is yet another fruit referred to as a custard apple. The papaw has a smooth, yellowish skin without the knobs or reticulations, which is characteristic of its tropical relatives. The shape is slightly elongated and curved, with the average length being four inches. The pulp is yellow, soft, and smooth; and it has a rich creamy flavour like that of both the banana and the pear. It has a heavy fragrance that some find offensive, but it can be eaten raw or baked and made into various desserts.

FUN FACTS ABOUT PAPAYAS

BACKGROUND INFORMATION ON PAPAYAS
Papayas are pear-shaped tropical fruits with thin skin that ranges in color from dark green to golden yellow. Like many other fruits, papayas continue to ripen after harvesting. When they are ripe and ready to eat the skin will be golden yellow and the fruit will be slightly soft. The flesh of ripe papayas can be yellow, orange, pink or even red, depending on the variety. No matter what color it is the yummy fruit tastes like a cross between melons and peaches.

TYPES OF PAPAYAS
There are two types of papayas grown around the world. Hawaiian papayas (also called “Solo” papayas) are usually about 6 inches long and typically weigh about a pound. Mexican papayas are much larger. They can grow up to 24 inches long and weigh up to 10 pounds! Because of their large size, Mexican papayas are usually sold in chunks. Hawaiian papayas are usually much sweeter than the Mexican type.

HOW DO PAPAYAS GROW?
Many people are surprised to learn that the papaya tree is actually an herb, but unlike many of its cousins, this herb can grow 10 or 12 feet tall! The Mexican variety can grow even taller. Papaya trees can be one of three sex types: male, female or hermaphrodite. Only the female and hermaphrodite trees produce fruit, but the quality of the fruit is not the same. Fruit from the hermaphrodite trees is the best, and is the fruit you’re likely to find in a supermarket.

WHERE DO PAPAYAS GROW?
The papaya tree is native to Mexico and Central America, but the trees are now grown in every tropical and subtropical country. Brazil is the leading papaya producing country, but most of the papaya sold in the U.S. comes from Mexico. Papaya grown in Hawaii is usually sold to Canada and Japan.

GREAT WAYS TO EAT PAPAYAS
Fresh papaya makes a great snack! It’s so sweet and refreshing. Before you eat a papaya, make sure it is ripe by gently pressing it with your thumb. If you can press it in a bit, it’s ready to eat. Just cut the papaya in half, scoop out the seeds, and then scoop out and eat the delicious fruit. Papaya is also yummy mixed with other tropical fruits like mango, bananas and pineapple. It’s fun to make a tropical fruit salad for dessert! You can also buy canned tropical fruit salads that include papaya.

ARE PAPAYA SEEDS EDIBLE?
Most people only eat the sweet delicious flesh, but you can also eat the small, black seeds in the center of the fruit. The seeds taste like black pepper. People in some countries use papaya seeds in place of black pepper corns.

NUTRIENTS IN PAPAYAS
One-half of a Hawaiian papaya counts as one serving of your 5 A Day. A serving of papaya is an excellent source of vitamin C and a good source of fiber and folate. Papayas also contain beta-cryptoxanthin, an antioxidant phytochemical found in many orange-yellow fruits and vegetables that helps protect cells from the harmful effects of pollution.

This fact sheet is provided courtesy of Dole Food Company’s Nutrition & Health Program.
© 2002 Dole Food Company, Inc.