sábado, 13 de outubro de 2012

Destaque do artigo "Actualización en fitoterapia y plantas medicinales"

Fitoterapia baseada em evidências

Plantas medicinais com evidência para seu uso A, B e C e de uso tradicional (tabela 1). Baseada em Naturalstandard (disponível em: http://www.naturalstandard.com), uma das entidades científicas mais reconhecidas na área da fitoterapia (tabela 2).


Título: Actualización en fitoterapia y plantas medicinales
Autores: Gemma Baulies Romero (Pediatra ABS La Llagosta. Barcelona. España) y Rosa María Torres Castella (DUE. ABS Ciutat Meridiana. Barcelona. España).
Link:

Brooklyn, Nova Iorque, maior horta urbana em altura do mundo

Fonte da informação:

Recipiente para hortaliças


A criação é do designer sueco Måns Salomonsen.

Como fazer cidades: “Guerrilheiros urbanos” e os Jardins Urbanos em Berlim

Com a expansão e crescimento das cidades, acabam surgindo espaços aparentemente residuais, que, no esquecimento das autoridades, mas no cuidado de seus usuários, tornam-se áreas potenciais para impulsionar projetos de transformação urbana alternativos. Assim, ouvimos cada vez mais sobre os “guerrilheiros urbanos”, organizações de cidadãos ativos aplicando o conceito de placemaking, cujos projetos são desenhados pelas mesmas pessoas que vão usá-los. Nesta ideia, lista-se o caso de Prinzessinnengärten (Jardim das Princesas), no bairro de Kreuzberg, Berlim, a partir da iniciativa de dois amigos que alugaram um espaço de  para construir um jardim urbano para a comunidade local.

O cenário é um terreno de 6000 m2 abandonado por quase meio século, mas com alto potencial pela intensa afluência de tráfego, em um setor da cidade que carecia de áreas verdes. Inspirados no êxito das granjas comunitárias em Cuba, este grupo de empreendedores urbanos transformou seus jardins em espaços públicos, sem uma imagem preconcebida do que seria e sem um plano diretor a ser seguido.

Desde o século XIX, a Alemanha desenvolveu uma história em relação aos jardins urbanos, quando o Estado cedia terrenos a grupos de poucos recursos para poder cultivar seus alimentos. A palavra “Schrebergärten” alude a estas pequenas porções de terra para realizar jardinagem dentro das áreas urbanas. Este tipo de prática de iniciativas coletivas no espaço público, reforçam o intercâmbio entre bairros e o desenvolvimento das comunidades.

Os fundadores, Robert Shaw e Marco Clausen, inspiraram-se na agricultura urbana em Cuba, como plataforma de desenvolvimento local e com sentido comunitário. Encontra-se um nicho de mercado que permite conjugar os interesses de uma comunidade em torno do uso ativo da paisagem, ao mesmo tempo atenuando os efeitos da crise alimentária e econômica. Quando o território se torna espaço de interesse comunitário e cenário de novas práticas de apropriação, obtêm-se capital humano e reduzem-se as barreiras burocráticas para gerar maiores transformações urbanas.

Nesta linha, a granja urbana do Jardim das Princesas permitiu cultivar as relações no interior da comunidade através de uma mesma atividade de interesse: trabalhar hortas e jardins. Os empreendedores geraram um espaço de aprendizado e capacitação em torno das hortas urbanas para difundir os principais aspectos da biodiversidade local. Ao mesmo tempo, construíram atrativos como um café, onde são preparados pratos com ingredientes provindos dali, ajudando a saldar uma parte das despesas incorridas. Os alimentos, dessa forma, não percorrem grandes distâncias para chegar ao prato e a cadeia de produção de consumo é nula.

Um dos princípios sugeridos é não enrijecer as atividades que ali se realizam, permitindo gerar práticas que extrapolam a outras escalas e localidades. Utilizando sacos de arroz, tetrapack e gavetas para cultivar tomates, alface e batatas, são construídos jardins unitários, replicáveis e adaptáveis a diferentes espacialidades. Os jardins urbanos podem assim ser acessíveis a qualquer pessoa que queira começar a plantar, a partir de seu próprio jardim ou espaço público.

Já publicamos sobre as vantagens de utilizar espaços residuais para implementar jardins urbanos, determinando novas maneiras de fazer cidades. Muitos destes são aparentemente negligenciados, porém configuram uma maior relação entre os cidadãos e o entorno natural, como o simples fato de ter a ciência sobre quais os produtos da temporada. Estas iniciativas rompem com o paradigma de que para obter áreas verdes urbanas devem-se conservar terrenos verdes intocados dentro das cidades. Parques e praças  podem existir a partir da participação ativa dos cidadãos – que dista bastante da passividade da reserva -, onde sua sobrevivência depende do impulso e manutenção de quem está constantemente envolvido.

 



Fotos: Revista PLOT

Data: 03.08.2012
Texto: Arq. e Urbanista Dominique Mashini
Link:

“Public Farm 1″: Hortas públicas no Queens, New York







Referência:
Helm , Joanna . "“Public Farm 1″: Hortas públicas no Queens, New York" 07 Aug 2012.ArchDaily. Accessed 13 Oct 2012. <http://www.archdaily.com.br/62917>

“Volet Végétal”: Horta urbana nas alturas

Referência: 
Helm , Joanna . "“Volet Végétal”: Horta urbana nas alturas" 04 Oct 2012. ArchDaily. Accessed 13 Oct 2012. <http://www.archdaily.com.br/73584>

Fotos: © Barreau & Charbonnet






Nigéria: Researcher identifies local plants with antifungal properties


A Nigerian researcher has identified no fewer than 520 local plants that could be used to treat fungal skin infections, control water hyacinth, biodegrade crude oil spill, prevent dental decay, and control uterine contraction and bleeding during child birth.

A PROFESSOR of Botany at the University of Lagos, Adedotun Adeyinka Adekunle, has documented 520 plant species with proven antifungal properties.

Adekunle in his Inaugural lecture, titled “Fungi: Friends or Foes to Mankind,” delivered last week at the University’s main auditorium, said: “Several studies were carried out on the purification of the antifungal principle from Nigerian plants. The active antifungal ingredient was tested on human fungal pathogens (dermatophytes) as well as on plant pathogens. It is always necessary to develop new natural drugs because of resistance to existing drugs by microorganisms like fungi.

“A survey of medicinal plants used in the treatment of skin rashes, eczema, athlete foot and ring worm in the south western, Nigeria was carried out. A medicinal plant list of 520 plant species with antifungal properties was documented.”

Adekunle who specializes in mycology (the study of fungi) said phytochemical properties of some of the plant extracts were investigated and were found to contain flavonoid, saponins, terpenes and tannins with fungicidal properties on dermatophytes such as Epidermophyton floccosom, Mucor mucedo (opportunistic), Microsporium audonii, and Trichophyton verrucosum.

Adekunle and his team of researchers also investigated the antifungal activity of four Nigerian chewing sticks from the stem or root of Angeissus schimperi (ayin in Yoruba), Distemonathus benthmianus (ayan in Yoruba), Vernonia amagdalina (orin ewuro in Yoruba, bitter leaf) and Zanthoxylum xanthoxyloides (orin ata in Yoruba).

“This study was set up to further scientifically support the use of chewing sticks in dental care by the Nigerian natives. It was found that the extracts of these chewing sticks were potent against fungi used,” he said.

The mycologist and his team also carried out another study on the time of leaf harvest (in a 24 hour rhythm) and antifungal activity of Acalypha wilkesiana (lara pupa in Yoruba) leaf extracts. Acalypha wilkesiana is used to treat skin rashes in babies (ela in Yoruba).

He explained: “The Nigerian traditional medicine practitioner believe that plants sleep at night between 7pm to 5am for their medicinal purpose. However, our study discovered that the best period of harvest of the Acalypha wilkesiana leaf was 3am. The leaves harvested at 3am had the highest concentration of corilagin and geranin, which are the antifungal active ingredients hence had the highest zone of inhibition on the fungi.

“There was a definite change in the antifungal activity of extracts of Acalypha wilkesiana leaves harvested at different times of the day (3am, 6am, 9am, 12noon, 3pm, 6pm, 9pm and 12 midnight). The least activity was recorded from leaves harvested at 12noon. Our report did not agree with the claims of the Nigerian natives to harvest plants for medicinal purpose only during the day light in the case of Acalypha wilkesiana leaf.”

Adekunle and his team also studied the efficacy of preserving plant seeds against fungi using wood ash of some tropical trees in Nigeria. The wood ash of nine Nigerian trees: Khaya grandifolia; Nauclea diderrichi; Piptadeniastrum africanum; Mangifera indica; Mansonia altissima; Triplochiton scleroxylon; Ceiba pentandra; Terminalia superba; and Terminalia ivoriensis were used to preserve beans, maize and melon seeds.

“The seeds stored with ashes of Nauclea diderrichi and Piptadeniastrum africanum were the most effective stopping fungal growth and eliminating weevils. The wood ashes used compared favourably with the orthodox fungicides benlate. The wood ash of these plants contained flavonoids and tannins which stop fungal infection and preserve the seeds.”

Adekunle with his colleagues from the department of biochemistry have isolated a pathogenic fungus called Myrothecium roridum that is able to destroy the water hyacinth, ‘eat up’ the whole plant, within five days post inoculation on the leaves. “The fungus can thus control the water hyacinth. The fungal action is systemic and host specific. On further investigation we isolated and purified a phytotopxin and mycoherbicide from Myrothecium roridum. With this discovery in 2006, we won the Faculty Best Researchers Award at the University of Lagos research fair. We have sent our findings and proposal to the Ministry of environment, Lagos state for further discussions on the biocontrol of water hyacinth in Lagos waters using this fungus,” he explained.

Adekunle and his team have also investigated the potential of alkaloids from Panicum maximum floret infected with the fungus Tilletia ayresii in the control of uterine contraction using bioassay guided fractionation technique.

They wrote: “Our aim of conducting this research was to discover cheaper and easily accessible drugs of Nigerian origin for controlling uterine contraction, which led to expulsion of placenta and subsequent control of bleeding after childbirth. The only source of the uterine contraction drug, ergometrine or ergot alkaloids before our study was from ergot or rye, a temperate plant that cannot grow in the tropics, Nigeria inclusive. Hence, it is imported with scarce foreign exchange.

“Ergot of rye is an infected rye floret by the fungus Claviceps purpurea. Claviceps purpurea infects the ovary of its host, rye, just as Tilletia ayresii infects the ovary of its own host, Panicum maximum (Guinea grass), a tropical plant found in Nigeria.

“We discovered an alkaloid as the active ingredient responsible for the uterine contraction in rats, from infected Panicum maximum floret purified extract. This discovery has been registered as a patent with the National Office of Technology Acquisition Promotion Agency (NOTAP).”

The botanist said his team has conducted a research to source fungi capable of biodegrading the petroleum oil from some Nigerian oilseeds such as soybean, maize, melon, Detarium senegalense, Treculia africana, and Irvingia gabonensis (Ogbonno in Yoruba). “We discovered that the pathogenic fungi isolated from the oil within 40 days. The oilseeds contain triacylglyceride, which is the vegetable oil hydrocarbon and it is biodegradable by the pathogenic fungi. This group of fungi was also able to biodegrade the hydrocarbon in the petroleum oil,” Adekunle said.

Adekunle in his inaugural lecture made several recommendations on how to improve scientific research in Nigeria. The professor of botany called for the establishment of a fungal collection centre to help in the confirmation of fungal identification. “Cultures are usually sent to America or United Kingdom. It used to be free, but now fungal confirmation attracts heavy fees in foreign currency.”

Adekunle want the government to introduce encouragement of research through financial reward for their work as practiced in South Africa. He said there is urgent need to establish a functional central laboratory for research in the University; promote and establish functional scholarship awards for post-graduate studies in all disciplines; and build accommodation for both members of staff and students; devise newer ways of providing sustainable electricity supply to the University.

Adekunle concluded: “These are my contributions in mycology, making fungi friends of man voluntarily or compulsorily scientifically. Fungi are indeed friends to humans.”

Data: 10.11.2012
Texto: Chukwuma Muanya

India: Prowling ground for First World’s knowledge pirates


Texto: Anirudh Chaudhary 
Posted December 13, 2011

In India it again boils down to soil. Post independence, India is again embroiled in a battle of its own kind to secure something that belongs to the country but is controlled by foreigners – The traditional knowledge. The knowledge to use all things natural, which has been passed over generations, is now threatened by Bio-Piracy.

Bio-Piracy refers to the use of intellectual property systems to legitimize the exclusive ownership and control over biological resources, products and processes that have been used over centuries in non-industrialized culture. This exclusive ownership can be legitimized by getting things “Patent” under the law. 

A patent is an exclusive right granted to an inventor for a limited period of time that prevents the distribution of the invention without permission. The objective of granting a patent is to encourage and develop a new technology but various MNCs round the globe are trying to pick it up as a ‘profit-making’ tool. 

It came as an eye opener when Delhi-based scientists noticed that globally some 5,000 traditional medicinal plants had already been patented, and more than 40% of them belong to Indian medicinal systems such as Ayurveda. Countless examples can be cited of MNCs patenting medicinal plants that have been used in India for more than 2,000 years. 

The patents laws that were earlier enforced region-wise are now being executed at global level with the help of bodies like United States Patent and Trademark Office (USPTO), EPO (European Patent Office) and WTO (World Trade Organization) and international treaties like TRIPS (Trade Related aspects of Intellectual Property Rights).

India has been fairly successful with its attempt of saving the traditional knowledge. It has managed to revoke a patent from W.R. Grace & Co. (US based company) over Neem, a medicinal plant of India, after a decade long court battle. 

India recently managed to revoke a patent over Mint (pudina) and Andrographis (kalamegha), medicinal herbs, granted by EPO to Chinese pharmaceutical giant- Livzon. India even sued Monsanto, a US based company over the use of Brinjal. 

 “This can send a different message to the big companies for violating the laws of the nation,” said K.S. Sugara, Member Secretary of the Karnataka Biodiversity Board, to France 24 concerning the lawsuit. “It is not acceptable that the farmers in our communities are robbed of the advantage they should get from the indigenous varieties.” 

The never-ending controversial patent list contains some names like Neem, hill turmeric, brinjal, Basmati,black plum (Jamun), various GM seeds and even ‘Atta Chakkis’, the traditional methods of producing the flour (atta) used  by Indians since ages.

Keeping these proliferating patent controversies in mind, India also took some initiatives to create a reliable and official database of the medicinal preparations on the basis of traditional knowledge called TKDL (Traditional Knowledge Digital Library). 

The project TDKL initiated in 2001 by the Department of Ayurveda, Yoga & Naturopathy, Unani, Siddha and Homoeopathy which provides information on traditional knowledge existing in the country, in languages and format understandable by patent examiners at International Patent Offices (IPOs), so as to prevent the grant of wrong patents. TKDL thus, acts as a bridge between the traditional knowledge information existing in local languages and the patent examiners at IPOs. 

The Intellectual Property Rights (IPR) game is difficult for most of the Indian companies as it is costly affair to deal with. It approximately costs around USD 2,50,000 in defending and enforcing a patent during its life-time, even after which the things remain uncertain. 

Owing to such price tags the industries bottom line is: ‘No Patents, No Benefits’ and in this blind race some MNCs even tried to patent the Yoga Asanas but India took a dynamic step and managed to void their petitions by declaring that about 200,000 traditional treatments are ‘public property’. 

Not only India but Africa and Latin America have been the prowling grounds for First World’s knowledge pirates. But India lies on a completely different plain as it has raised a strong voice against it and is emerging as an effective battler against these politically illicit actions. 

Link:

Lantern Bug

Fulgora lampestris
Foto: http://www.projectnoah.org/spottings/7111102

Spicebush Swallowtail larvae

Papilio troilus 
Foto:
http://www.projectnoah.org/spottings/6901876/fullscreen

Fringed Spider Flower


Cleome rutidosperma
Foto:
http://www.projectnoah.org/spottings/15155072/fullscreen

Estados Unidos: Researchers study wild tomatillo as cancer-fighter


WICHITA, Kan. —  For decades the native prairie plant with tomato-like vines, and marbled-sized fruit covered in thin husks, has sprawled across the Kansas prairie in relative obscurity. 

But scientists from around the world are now noticing the wild tomatillo, and wondering if it might provide a major medicinal breakthrough.

"We've found compounds from the wild tomatillo that have strong anti-cancer properties against breast cancer, skin cancer, thyroid cancer and brain cancer in our early studies," said Mark Cohen, cancer physician and research scientist who has been working with the plant for more than two years.

"It's very exciting because not only do those compounds occur naturally, but they're more potent than some drugs currently on the market for these diseases."

Cohen said initial research has been done against human cancer cells in laboratory containers and mice. Things are progressing well enough that human-based trials could begin in about two years, he said.

It seems the deeper the botanists, medicinal chemists and cancer researchers dig into wild tomatillos, the more promise the prairie plant holds. 

"We've found 15 new molecules in the plant previously not known to science," said Barbara Timmermann, University of Kansas medicinal chemistry chair. "Nobody knew they existed and several of them are so active against cancer." 

And it's not like this is some super-delicate plant from some far away corner of the Amazon.

Wild tomatillos, Physalis longifolia, are a tough, prolific prairie plant currently thriving over much of the central United States. (They're related to a domestic variety of tomatillo, but scientists don't know if it has similar characteristics.)

But promised funding was abruptly cut less than halfway through the five-year research project.

"We are having fantastic data, and things are moving so well, then they just pulled the rug out from under us," Timmermann said, of money from Heartland Plant Innovations. "It's very unfortunate, and very disappointing."

The Native Medicinal Plant Research Program began in 2010 as a joint venture using the strengths of the Kansas Biological Survey, the KU School of Pharmacy and the KU School of Medicine. 

Timmermann and Kelly Kindscher, a biological survey senior scientist, have long seen the Kansas prairies as a potential pharmacy waiting to be explored.

"Everybody has been going to the rain forest and other exotic places for research," said Timmermann, who has about 30 years of experience researching medicinal plants, "but we knew the Midwest had so many plants nobody had ever really looked at." 

Kindscher, a noted expert on America's prairies, had also learned that for centuries native tribes were utilizing a number of plants for medicinal purposes before the state was settled.

"They weren't collecting them randomly," Kindscher said. "They'd learned what to use, and used them in many cases fairly effectively."

He said modern research has shown most do indeed work.

Kindscher said any medicinal benefits found in plant compounds are mostly coincidental. Most are produced to protect the plant in some way or another.

"Plants can't run and they can't just grow spines if they don't have them, so they need some kind of chemical defense against being eaten by insects or something," he said.

They also may help them survive tough conditions, like floods and drought. While Kindscher and crew eventually provided about 200 different species of prairie plants for testing, wild tomatillos quickly gained the most attention because of the findings in Timmermann's lab.

As well as testing how the wild tomatillo compounds perform against cancer, the plants were also tested to see how they react to other kinds of human cells.

It would be possible, Cohen said, for a compound to be very aggressive against cancer but too toxic to healthy human cells to become a viable treatment.

Fortunately, that hasn't been the case so far.

"It's very exciting that (wild tomatillo compounds) do have a strong potency effect against cancer and do not have significant toxicity against other cells so far in our evaluations," said Cohen, who is directing laboratory testing on the wild tomatillo compounds furnished by Timmermann.

Initially Cohen did so at the KU School of Medicine. He took the chores with him to a new job at the University of Michigan.

If all goes very well, Cohen said clinical trials with humans could begin within about two years. Wild tomatillo-based drugs could possibly hit the general market within about seven years.

It's too early to know how the medicine could be administered, if it passes all testing and trials.

Cohen said it could probably be injected into patients.

An oral wild tomatillo extract could be another option.

Kindscher said some of the highest levels of cancer-fighting compounds are found in the plant's fruit.

"The fruit is edible, and actually tastes very good," he said, "especially when it's ripe."

Acquiring enough of that fruit shouldn't be a problem in the future.

Wild tomatillos are so common Kindscher referred to them as "a common field weed" that grows on native prairies, pastures and farmlands, roughly from New Mexico to Montana and as far east as Ohio.

"It's probably one of the few (prairie) plants that are doing about as well as ever," he said. "It's common because it can grow in a lot of areas. Unlike a lot of prairie plants it does well on disturbed soils."

He said it grows well along roadsides or where the soil has been scarred by livestock.

It's common in farm fields, too. Kindscher is certain it could be grown commercially, too.

The perennial plant has proven to be hardy to temperature and rainfall extremes.

But one thing this miracle plant cannot do, is pay for its own research. All three scientists said funding is now their greatest worry.

Timmermann said Heartland Plant Innovations originally agreed to pay $5 million over five years to fund the research.

Heartland is a Manhattan-based bio-technology company backing plant-based research. In the spring, nearing the end of the program's second year, Timmermann was told funding would stop immediately.

"This just comes at a very bad time," she said. "This is when we should be growing." Currently the program is running on funding she'd saved from the previous two years.

Forrest Chumley, Heartland Plant Innovations' president, said the decision to stop the funding at about $2.5 million was a business decision.

"We're a for-profit company so we focus on projects where we can make the greatest difference. We've decided it's time to really focus on wheat development," he said. "We're really proud of what (the Native Medicinal Plant Research Program) has accomplished, and think it has great potential."

Chumley said budget cuts to the state-financed Kansas Bioscience Authority, one of his main sponsors, also left his group with less money.

Researchers are now searching for further funding. "It's very exciting that this may represent some new cancer drugs," Cohen said. "Unfortunately our biggest challenge is now acquiring more funding so we can move things to the next level."

Data: 12.10.2012
Link:

Marrocos: Plants could be at the root of new jobs

Could the medicinal plant sector become a catalyst for development in Morocco? The INPMA, the largest institute in the country for research in aromatic and medicinal plants, certainly thinks so. Morocco has a rich and diverse heritage, but its market is supplied by high value-added products imported from abroad, while at the same time Morocco exports its plants in a natural state. This is a situation that has to change, and this activity is at the centre of the European project MAP2ERA, which aims to strengthen international research and cooperation between the INPMA and the European Research Area.

This is part of a series of features on projects funded by the EU’s Regional Programme, prepared by journalists and photographers on the ground or the EU Neighbourhood Info Centre.






Data: 20.09.2012
Link:

Paulo Freire


Sem a curiosidade que me inquieta, que me insere na busca, não aprendo, nem ensino. 

Lisboa: Uma horta para plantar legumes... e a cidadania


Texto: Bruno Abreu

No centro das grandes cidades, as hortas passam um pouco despercebidas, e nem toda a gente lhes dá o devido valor. Ao lado do Bairro da Picheleira, em Lisboa, uma horta escolar fez toda a diferença. «Em vez de os alunos saltarem os muros para fugir da escola, havia miúdos problemáticos que saltavam para dentro da escola para virem ajudar na horta», conta o professor Nuno, da EB Engenheiro Duarte Pacheco, no Beato. O sucesso imediato fez com que a horta se tornasse pequena para tanto entusiasmo. 

Esta sexta-feira foi, portanto, inaugurada a segunda parte do projeto: uma horta comunitária localizada ao lado da escola que foi posta ao serviço do bairro. O terreno estava ao abandono, mas agora tem estacas a segurar a terra e está tudo pronto para plantar. A Presidente da Assembleia Municipal de Lisboa, Maria Simonetta Luz Afonso, deu a primeira cavadela na terra, uma forma simbólica de inaugurar a obra.

Agora a horta não é apenas um monte de terra para plantar cenouras ou manjericão, mas mais do que isso. Planta-se também o futuro. «Aqui as crianças aprendem a cidadania. Foram eles próprios a terem a ideia, a apresenta-la e a avançarem com ela. Envolveram-se, envolveram as comunidades. Foi um trabalho de grupo que permite que aprendam a olhar para a cidade», explicou a presidente da Assembleia Municipal.

E de facto assim é. O entusiasmo dos alunos, com idade de escola primária, é evidente desde que apresentaram a proposta à câmara. Escolheram o espaço, na altura degradado e forrado a ervas daninhas, como o local onde iam crescer os seus legumes. «Esta foi uma iniciativa dos alunos e que partiu da escola. Visa criar um sentido de responsabilidade inerente à cidadania. É um exemplo», disse por seu lado João Casanova de Almeida, secretário de Estado do Ensino e Educação Escolar, também presente na inauguração.

Envolvido no projeto esteve também a Junta de Freguesia do Beato, que tomou a horta como projeto prioritário para o bem-estar da comunidade. «A horta é agora um espaço público, que não estava a ser usado, mas que agora poderá ser cultivado. Em tempo de crise é importante fomentar estes valores e promover a educação cívica e a cidadania ambiental. As próprias crianças podem também aprender que os legumes não vêm dos supermercados mas sim da terra», afirmou o presidente Hugo Xambre Pereira.

Um molho de manjericão foi transferido da horta da escola para a comunitária, onde vai começar a florir, juntamente com este projeto.
Foto de Alexandre Pona/ ASF
Data: 12.10.2012
Link:

México: De planta medicinal a fitofármaco

La Etnofarmacología es un área de investigación en la Facultad de Ciencias de la Universidad Nacional Autónoma de México (UNAM), la cual tiene como base el conocimiento tradicional, en especial de las plantas medicinales, para darle un enfoque científico.

Con base en ello, un equipo de investigadores de esa Facultad comprobó mediante estudio científico que el guarumbo (Cecropia obtusifolia Bertol) controla los niveles de glucosa en pacientes con diabetes tipo II, de manera que puede utilizarse como complemento de otros hipoglucemiantes orales.

El estudio es dirigido por el doctor Adolfo Andrade Cetto, quien refiere que se probó la presencia de los principios activos del guarumbo en personas, en dosis diarias de 13.5 gramos de planta estandarizada en 500 mililitros de agua, es decir, en forma de té tomado en el transcurso del día, y se logró un efecto hipoglucemiante estadísticamente significativo a las cuatro semanas de uso, el cual se reflejo en los niveles de hemoglobina glucosilada.

Para obtener este resultado se contó con la colaboración de pacientes de reciente diagnóstico con diabetes tipo II, del Hospital Centro Médico Siglo XXI, del Instituto Mexicano del Seguro Social, bajo la dirección de la doctora Cristina Revilla Monsalve.

“Los principios activos de las hojas de Cecropia obtusifolia Bertol bloquean la liberación hepática de glucosa, por lo que el efecto seria similar al del fármaco metformina en pacientes con diabetes tipo II; por lo que ayudan a reducir los niveles de glucosa a lo largo del día”, indica el doctor Andrade Cetto.

El guarumbo es un árbol que en ciertas regiones de nuestro país encuentra las condiciones para su crecimiento. A decir del académico de la UNAM, esta planta debe ser cosechada en un determinado punto, ya que si se corta antes o después, no tendrá los efectos hipoglucemiantes.

La Etnofarmacología se basa en el uso tradicional que se da a las plantas, sobre todo con efectos medicinales, en las comunidades de nuestro país. “Se sabe que desde hace muchos años han sido utilizadas colectivamente como remedios caseros y de esa forma se administran también a niños, pero no hay pruebas pre-clinicas del guarumbo en este tipo de pacientes”, agrega el doctor Andrade Cetto.

El grupo de investigadores del departamento de Etnofarmacología de la Facultad de Ciencias efectúa trabajo de campo en comunidades rurales de Guerrero, Oaxaca, Hidalgo y Yucatán.
El doctor Andrade Cetto realiza estudios etnofarmacologicos en diabetes tipo II desde 1991, año en que inició su maestría. Ya ha estado en Alemania, para realizar su doctorado y se interesó en transferir el saber popular mexicano a un estudio más profundo, de forma que fuera útil para la medicina.

Los resultados de la investigación con el guarumbo como hipoglucemiante están en vía de patente tramitada por la UNAM, ante las claras posibilidades de derivar en fitofármacos producidos industrialmente.

El especialista en Etnofarmacología reitera que el té de Cecropia obtusifolia Bertol puede ser un coadyuvante para los pacientes con diabetes tipo II de diagnóstico reciente, pero su uso no substituye a ningún medicamento. “Se ha comprobado que la planta no es genotóxica, pero aún hacen falta estudios de su bioseguridad a largo plazo; hay que tomar en cuenta que al comprar la planta en mercados u otros sitios no hay una garantía de la composición química de la misma, factor fundamental en su efecto hipoglucemiante, por lo que puede recomendarse su uso en pacientes diabéticos pero con las reservas del caso.

La Etnofarmacología es una ciencia interdisciplinaria, ya que abarca las observaciones en campo, la descripción del uso y preparación de los remedios, la determinación botánica del material obtenido y los estudios fitoquímicos que son muy importantes para aislar los compuestos presentes en las plantas, así como los estudios farmacológicos.

La Etnofarmacología ha cobrado gran relevancia en años recientes debido al interés de la industria farmacéutica por las plantas y sus efectos medicinales para encontrar agentes terapéuticos en el tratamiento de enfermedades cuya incidencia crece de forma alarmante, como la diabetes.

Texto: Raúl Serrano
Data: 01.10.2012
Link:
http://www.invdes.com.mx/suplemento-noticias/2185-de-planta-medicinal-a-fitofarmaco