The first literary reference to papayas dates back to 1526, when they were found in the Caribbean coast of Panama and Colombia and described by the Spanish chronicler Oviedo. Thanks to its several hardy seeds (which can last for up to the 3 years in cool and dry conditions) the plant spread relatively easily throughout the tropics, and has become naturalized in several regions, especially those abundant with water and fertile soils. Papayas are thought to be native to tropical America, in a region that goes from the Andes of South America to Southern Mexico.
Papayas during the Spanish exploration
They were spread to the south by Indians (aboriginal Americans), and was later spread to the whole Caribbean by Spanish explorers, who also carried it to Europe and the Pacific Islands. Papayas could be found in any tropical region by 1650, and later spread to Hawaii around the end of the 18th century.
A papaya harboringringspot virus. The virus was overcome in 1998 with genetic engineering of papaya plants Hawaii remains today the only state producing papayas commercially. In Florida, during the early 1900, there was a small papaya industry, but it was rapidly destroyed by viral diseases (such as papaya ringspot virus) that are still threatening papayas in other areas: the Hawaiiand industry underwent a decline recently for this reason.
Genetic Engineering of the Sunrise cultivar
However, new technologies have allowed biotechnologists at the University of Hawaii, in 1998, to genetically modify papaya cultivars of the species “Sunrise”, inserting a gene in their DNA that confers them viral immunity. This application of engineering made papayas the first genetically modified fruit for human consumption, and it appears to have achieved a lot of success! Since the experiment, most of the papaya plants in Hawaii have been replaced by the new genetically modified Sunrise cultivar.
Modern History and Taxonomy
Papayas belong the Caricaceae family, which was recently at the center of taxonomic arguments: new information increased the number of genera from 4 to 6, placing them in the monophyletic clade of glucosinolateproducing families that includes the Brassicaceae. The bulk of the genus was comprised by the newly named Vasconcellea species of South America, but several morphologica, molecular, reproductive and biogeographical traits suggest that Carica papaya is actually monospefic, and distinct from Vasconcellea. Botanically, the history of papayas is very curious: it was domesticated in Central American from progenitors that were nearly inedible and weedy, and has undergone lots of changes and mutations during centuries of human selection, that modified its fruit size, flesh color, mating system and growth habits.
Papayas are not only colorful and tasty, but they also provide several vitamins (especially of the B group), several antioxidant molecules such as flavonoids, carotene and vitamin C, as well as folates, trace minerals, pantothenic acid, potassium, magnesium and dietary fiber. This wide range of micronutrients makes papayas very nutritious, and their health benefits are numerous, ranging from reduced risks of developing cardiovascular diseases to protection against colon cancer. A proteolitic enzyme contained in papayas, papain, is very similar to bromelain (pineapples’ equivalent), which is often used to treat allergies and is commonly given to treat sports injuries.
Papayas protect against heart disease
Papayas contain high amounts of antioxidants, both of hydrosoluble and lipid-soluble varieties, including vitamin C, vitamin E and A (through their concentration of retinol-equivalents in carotenoids). This wide range of antioxidants helps prevent the oxidation of cholesterol, which has been proven to be one of the main causes and necessary steps to develop atherosclerosis. In fact, when cholesterol is oxidized, it tends to stick and form atheromas (atherosclerotic plaques) in the sheaths of blood vessel walls. These atheromas tend to grow with time, eventually restricting blood flow and causing ischemia, strokes and heart attacks.
Vitamin C and E prevent the oxidation of cholesterol, probably because of their association with an enzyme called paraoxonase, which has been shown in several studies to inhibit LDL and HDL cholesterol oxidation. The protective effect of papayas is further enhanced by their content in dietary fiber, which again has been linked to a reduction in total blood cholesterol levels. Papayas are also rich in folates: protein-like compounds that are necessary for converting homocysteine into benign aminoacids such as methionine and cysteine. Homocystein has been shown to directly damage blood vessels, and high blood levels of homocysteine are classically reported in medical textbooks as a risk factor for heart attacks and strokes.
Protection against digestive diseases
The high content in dietary fiber is helpful for reducing the risk of developing digestive diseases: fiber binds to cancer-promoting toxins in the colon, preventing their absorption. The presence of vitamin C, A and E, as well as folates and carotenoids is itself sufficient to consider papaya anti-carcinogenic: high levels of antioxidants have classically been shown to substantially reduce cancers and even the aging process in our cells.
Papayas have anti-inflammatory properties
Several digesting enzymes called protease are present in papayas: the most important are papain and chymopapain. These enzymes have been shown to lower inflammatory responses and hasten the healing of burn wounds. Again, these compounds act synergystically with antioxidants such as vitamin C, A and E and carotenoids to reduce general inflammation. This means that eating papayas may reduce common symptoms of acute inflammation, such as arthritis and asthma.
Papayas and Green Tea against Prostate Cancer
A case-control study, published by the Asia Pacific Journal of Clinical Nutrition, involved 130 prostate cancer patients and 274 hospital controls. Subjects were given different quantities of green tea and lycopene-rich foods, such as papayas and tomatoes. The study concluded that men drinking the most green tea had an 86% reduction in the risk of prostate cancer, compared to those drinking the least. Similarly, men who ate the most lycopene-rich foods had an 82% reduction in the relative risk of developing prostate cancer. Further research suggests that combining these two food choices has an even greater synergystic effect on risk reduction.
Protection from Macular Degeneration
A study published in the Archives of Ophtalmology involving 110,000 subjects of both sexes evaluated the effects of consuming fruits, vegetables, antioxidant vitamins such as A,C and E and carotenoids on the risk of developing Age-Related Macular Degeneration. Macular Degeneration is the primary cause of sight loss in adults, and the study found that by eating at least 1.5 servings of fruits daily, one can reduce the risk of developing the disease by 36%. Risk reduction was not directly linked to consumption of vegetables, antioxidants and vitamins, but to the consumption of whole fruits: the optimal level, according to the study, is three servings a day, which can be easily reached by eating papaya cubes with your morning cereal or dressing up salads with other fruits.
Papayas promote Lung Health
Research conducted at Kansas State University suggests that an adequate intake of Vitamin A (such as the retinol-equivalents found in papayas) may greatly reduce the damage cause by smoke. Richard Baybutt, associate professor of nutrition at Kansas State, made an astonishing discovery while studying connection between lung inflammation, emphysema and vitamin A: benzopyrene, one of the most toxic and dangerous carcinogens in cigarettes, is linked (and actually appears to cause) vitamin A deficiencies. His former research showed that lab animals tend to develop emphysema if fed a vitamin A-deficient diet. He then hypothesized and proved, with research, an inverse relationship: high amounts of vitamin A are protective against emphysema, especially when induced by benzopyrene (found in cigarette smoke). Baybutt hypothesizes vitamin A consumption may be the reason why some smokers do not develop emphysema despite smoking large amounts of cigarettes during their lifetimes.
Baybutt believes vitamin A’s protective effects may help explain why some smokers do not develop emphysema. In his own words:”There are a lot of people who live to be 90 years old and are smokers. Why? Probably because of their diet..The implications are that those who start smoking at an early age are more likely to become vitamin A deficient and develop complications associated with cancer and emphysema. And if they have a poor diet, forget it.” http://www.papayalovers.com/papayas/History+of+Papayas/