Annual IUCN 'red list' of endangered species includes upgraded threat to tree whose bark is harvested for cancer treatment
In pictures - the IUCN red list update 2011Thursday 10 November 2011
A species of Himalayan yew tree that is used to produce Taxol, (Paclitaksel, Docetaksel) a chemotherapy drug to treat cancer, is being pushed to the brink of extinction by over-harvesting for medicinal use and collection for fuel, scientists warned on Thursday.
The medicinal tree, Taxus contorta, found in Afghanistan, India and Nepal, has seen its conservation status change from "vulnerable" to "endangered" on the IUCN's annual "red list" of threatened species.
Taxol was discovered by a US National Cancer Institute programme in the late 1960s, isolated in the bark of the Pacific yew tree, Taxus brevifolia. All 11 species of yew have since been found to contain Taxol. "The harvesting of the bark kills the trees, but it is possible to extract Taxol from clippings, so harvesting, if properly controlled, can be less detrimental to the plants," said Craig Hilton-Taylor, IUCN red list unit manager.
"Harvest and trade should be carefully controlled to ensure it is sustainable, but plants should also be grown in cultivation to reduce the impact of harvesting on wild populations," he added.
The red list is currently the most detailed and authoritative survey of the planet's species, drawn from the work of thousands of scientists around the globe. For the first time, more than 61,900 species have been reviewed. The latest list categorises 801 species as extinct, 64 as extinct in the wild, and 9,568 as critically endangered or endangered. A further 10,002 species are vulnerable, with the main threats being overuse, pollution, habitat loss and degradation.
Tim Entwisle from the Royal Botanic Gardens, Kew, said: "There are 380,000 species of plants named and described, with about 2,000 being added to the list every year. At Kew we estimate one in five of these are likely to be under threat of extinction right now, before we even factor in the impacts of climate change."
The Chinese water fir, for example, which was formerly widespread throughout China and Vietnam, is critically endangered. The main cause of decline is the loss of habitat to expanding intensive agriculture. The largest of the recently discovered stands in Laos was killed through flooding for a newly constructed hydropower scheme.
Some 25% of all mammals were deemed to be at serious risk, according to the list. The black rhino in western Africa has officially been declared extinct. The white rhino in central Africa is on the brink of extinction and has been listed as possibly extinct in the wild. In Vietnam, poaching has driven the Javan rhinoceros to extinction, leaving the critically endangered species' only remaining population numbering less than 50 on the Indonesian island that gave it its name.In the granitic Seychelles Islands, 77% of the assessed endemic flowering plants are at risk of extinction, including the Coco de Mer, which is illegally harvested for its supposed aphrodisiac properties.
But it is not all bad news for conservationists. Przewalski's horse, also known as the Mongolian wild horse, was listed as extinct in the wild in 1996. Thanks to captive breeding and a successful reintroduction programme, the population in central Asia is now estimated at more than 300 and the wild horse has improved its status from critically endangered to endangered.
"This update offers both good and bad news on the status of many species around the world," said Jane Smart, director of the IUCN Global Species Programme. "We have the knowledge that conservation works if executed in a timely manner, yet, without strong political will in combination with targeted efforts and resources, the wonders of nature and the services it provides can be lost forever."
The overall message is that biodiversity continues to decline and governments need to take action to achieve the goal of a 10-year plan that was agreed on the international biodiversity summit in Japan last year. It reads: "By 2020 the extinction of known threatened species has been prevented and their conservation status, particularly of those most in decline, has been improved and sustained."
_http://www.theguardian.com/environment/2011/nov/10/iucn-red-list-tree-chemotherapy
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_http://www.theguardian.com/environment/2011/nov/10/iucn-red-list-tree-chemotherapy
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Graviola Tree
Graviola tree is an evergreen tree native to the northern region of South America.
It is also found in a few countries ofSub-Saharan Africa, and
Southeast Asia. Also referred to as Soursop in many regions where it is found, this species is specifically referred to as Guanabana in Spain, Guyabano in Philippines and Athipazham in India. Owing to its various health benefits, graviola has become one of the major commercial crops in several parts of the world.
Cultivation
Graviola tree is a small tree which can grow up to a height of five to six meters. Its leaves are relatively large and green, with a glossy surface. The tree grows well in areas with high humidity and relatively warm winters. Temperatures below 49 degrees Fahrenheit are harmful for the growth of this species, and further fall in temperature can even cause the tree to die. The tree is grown in abundance in Mexico, Caribbean, Central America, Philippines etc. The plant is also grown in southern Florida, but the use is restricted to local consumption.
Fruit and Its Uses
The tree is most often cultivated for its prickly green colored fruit, which can grow up to a length of 7 to 12 inches, and weigh up to 5.5 lbs. This edible fruit contains white pulp and black seeds. The pulp is sweet in taste, which makes it an ideal constituent of various candies, ice cream flavorings as well as juices. In some places, it is also used as a dessert, while in some places, fruit bars or ice creams made from this fruit are quite popular.
Benefits
Salasanasuojattu sivu
In a 1976 plant screening program by the National Cancer Institute, Graviola leaves and stem
showed active toxicity against cancer cells, and researchers have been following up on these findings since.
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It is also found in a few countries ofSub-Saharan Africa, and
Southeast Asia. Also referred to as Soursop in many regions where it is found, this species is specifically referred to as Guanabana in Spain, Guyabano in Philippines and Athipazham in India. Owing to its various health benefits, graviola has become one of the major commercial crops in several parts of the world.
Cultivation
Graviola tree is a small tree which can grow up to a height of five to six meters. Its leaves are relatively large and green, with a glossy surface. The tree grows well in areas with high humidity and relatively warm winters. Temperatures below 49 degrees Fahrenheit are harmful for the growth of this species, and further fall in temperature can even cause the tree to die. The tree is grown in abundance in Mexico, Caribbean, Central America, Philippines etc. The plant is also grown in southern Florida, but the use is restricted to local consumption.
Fruit and Its Uses
The tree is most often cultivated for its prickly green colored fruit, which can grow up to a length of 7 to 12 inches, and weigh up to 5.5 lbs. This edible fruit contains white pulp and black seeds. The pulp is sweet in taste, which makes it an ideal constituent of various candies, ice cream flavorings as well as juices. In some places, it is also used as a dessert, while in some places, fruit bars or ice creams made from this fruit are quite popular.
Benefits
Salasanasuojattu sivu
Technical Data Report - Graviola
BIOLOGICAL ACTIVITIES AND CLINICAL RESEARCH
In a 1976 plant screening program by the National Cancer Institute, Graviola leaves and stem
showed active toxicity against cancer cells, and researchers have been following up on these findings since.
Thus far, specific acetogenins in graviola and/or extracts of Graviola have been
reported to be selectively toxic in vitro to these types of tumor cells:
reported to be selectively toxic in vitro to these types of tumor cells:
- lung carcinoma cell lines;
- human breast solid tumor lines;
- prostate adenocarcinoma;
- pancreatic carcinoma cell lines;
- colon adenocarcinoma cell lines;
- liver cancer cell lines;
- human lymphoma cell lines;
- and multi-drug-resistant human breast adenocarcinoma.
Researchers in Taiwan reported in 2003 that the main Graviola acetogenin, annonacin, was highly toxic to ovarian, cervical, breast, bladder and skin cancer cell lines at very low dosages, saying “annonacin is a promising anti-cancer agent and worthy of further animal studies and, we would hope, clinical trials.”
http://graviola.fi/graviola-amazonilta/graviola-clinical/
Current Practical Uses
Cancer research is ongoing on these important Annona plants and plant chemicals, as several pharmaceutical companies and universities continue to research, test, patent, and attempt to synthesize these chemicals into new chemotherapeutic drugs.
In fact, graviola seems to be following the same path as another well-known cancer drug—Taxol
From the time researchers first discovered an antitumorous effect in the bark of the pacific yew tree and a novel chemical called taxol was discovered in its bark, it took thirty years of research by numerous pharmaceutical companies, universities, and government agencies before the first FDA-approved Taxol drug was sold to a cancer patient (which was based on the natural taxol chemical they found in the tree bark).
With Graviola, it has taken researchers almost ten years to successfully synthesize (chemically re p roduce) the main antitumorous chemical, annonacin.
These acetogenin chemicals have a unique waxy center and other unique molecular energy properties, which thwarted earlier attempts, and at least one major pharmaceutical company gave up in the process.
Now that scientists have the ability to recreate this chemical and several other active acetogenins in the laboratory, the next step is to change the chemical just enough (without losing any of the antitumorous actions in the process) to become a novel chemical, which can be patented and turned into a new (patented) cancer drug.
(Naturally occurring plant chemicals cannot be patented.)
Thus far, scientists seem to be thwarted again—every time they change the chemical enough to be patentable, they lose much of the antitumorous actions. Like the development of taxol, it may well take government agencies like the National Cancer Institute and the National Institutes of Health to step forward and launch full-scale human cancer research on the synthesized unpatentable natural plant chemical (which will allow any pharmaceutical company to develop a cancer drug utilizing the research, as happened with taxol) to be able to make this promising therapy available to cancer patients in a timely fashion.
In fact, graviola seems to be following the same path as another well-known cancer drug—Taxol
From the time researchers first discovered an antitumorous effect in the bark of the pacific yew tree and a novel chemical called taxol was discovered in its bark, it took thirty years of research by numerous pharmaceutical companies, universities, and government agencies before the first FDA-approved Taxol drug was sold to a cancer patient (which was based on the natural taxol chemical they found in the tree bark).
With Graviola, it has taken researchers almost ten years to successfully synthesize (chemically re p roduce) the main antitumorous chemical, annonacin.
These acetogenin chemicals have a unique waxy center and other unique molecular energy properties, which thwarted earlier attempts, and at least one major pharmaceutical company gave up in the process.
Now that scientists have the ability to recreate this chemical and several other active acetogenins in the laboratory, the next step is to change the chemical just enough (without losing any of the antitumorous actions in the process) to become a novel chemical, which can be patented and turned into a new (patented) cancer drug.
(Naturally occurring plant chemicals cannot be patented.)
Thus far, scientists seem to be thwarted again—every time they change the chemical enough to be patentable, they lose much of the antitumorous actions. Like the development of taxol, it may well take government agencies like the National Cancer Institute and the National Institutes of Health to step forward and launch full-scale human cancer research on the synthesized unpatentable natural plant chemical (which will allow any pharmaceutical company to develop a cancer drug utilizing the research, as happened with taxol) to be able to make this promising therapy available to cancer patients in a timely fashion.
Ethnomedical Information for Graviola (Annona muricata)
Presence of Compounds in Graviola (Annona muricata)
Documented Biological Activities for Extracts of Graviola (Annona muricata)
IN VIVO RESEARCH
IN VITRO RESEARCH
Documented Biological Activities for Extracts of Graviola (Annona muricata)
IN VIVO RESEARCH
IN VITRO RESEARCH
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Read more at Buzzle: http://www.buzzle.com/articles/graviola-tree.html
Now Food Graviola Caps -kapseleihin käytetään Graviola puun lehdet.
Graviolan hedelmiä, siemeniä, kuorta, lehtiä ja juurta on Keski- ja Etelä-Amerikan sekä Karibian kansojen keskuudessa jo vuosisatojen ajan käytetty myös perinteisinä luonnonrohtoina saatujen kokemusten ja monipuolisiksi havaittujen vaikutustensa vuoksi.
Paitsi hedelmiä, myös sen siemeniä, varsia ja lehtiä on perinteisesti käytetty kansanlääkinnässä mitä erilaisemmissa terveysongelmissa ja erilaisempiin tarkoituksiin.
Parhaiten Graviolan käyttö tunnetaankin Etelä-Amerikassa, jossa sen kuoresta, juurista ja lehdistä on valmistettu teetä erilaisten vaivojen hoitoon. Perun Andien alkuperäiskansojen tiedetään käyttävän graviolan lehtiteetä lisäämään limakalvojen liman eritystä ja rauhoittamaan niitä.
Joissakin Perun osissa diabeetikot käyttävät sekä kuorta että lehtiä tasaamaan veren sokeria. Guyanassa lehtiteetä käytetään lähinnä elinvoimaa parantavana ja virkistävänä juomana, Braziliassa maksan toimintaa edistämään sekä Länsi-Intian saarilla puolestaan helpottamaan yskää ja avaamaan hengitystä.
Nykyisin myös tutkijat ovat kiinnostuneet graviolan perinteisestä käytössä ja sen mahdollisista vaikutuksista jopa joidenkin vakavien sairauksen hoidossa. Mm. New Yorkissa sijaitsevassa maailmankuulussa syöpätutkimuskeskuksessa Memorial Sloan-Kettering Centerissä, (MSKCC) tehdyissä tutkimuksissa on havainnut graviolalla olevan vaikutusta viruksiin, parasiitteihin sekä reumaan
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