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International Year of Chemistry

From molecules to organisms

The wealth of biodiversity in the Brazilian forests is also revealed in substances

LAURA TEIXEIRAWhen one talks about biodiversity, one of the main areas of the wealth of Brazil that comes to mind is usually plants and animals, in a huge variety of shapes, colors, sizes and types. Hardly anyone remembers the molecules that, with an equally amazing diversity, permeate this entire natural heritage. Among the few aware of the importance of chemistry are the speakers at the fourth meeting of the cycle of conferences organized by FAPESP – São Paulo Research Foundation and by the Brazilian Chemical Society, which is celebrating the International Year of Chemistry. Vanderlan Bolzani, from Paulista State University (Unesp) in Araraquara, Carlos Alfredo Joly and Anita Marsaioli, both from the State University of Campinas (Unicamp), on July 19, enchanted an audience composed largely, even though it was vacation time, of students from the Technical Institute at Barueri. The presence of these interested youngsters was precious for the speakers, who did not miss the chance to present hidden diversity and to point out promising fields of study and research.

“One of the goals of the International Year is to promote reflection on the importance of chemistry for sustainability,” said Dulce Siqueira Silva, from Unesp in Araraquara, coordinator of the day. A good starting point, echoed by the three speakers. The botanist Carlos Alfredo Joly spoke, precisely, about sustainability. He is the coordinator of Biota FAPESP, which, in its first 10 years of activity making an inventory of the biodiversity of the ecosystems in São Paulo, showed how scientific knowledge can help in its preservation (see text). Indeed, it is already contributing to it. The maps produced by Biota to indicate areas for conservation and restoration in the Cerrado and the Atlantic Forest in the State of São Paulo (see Pesquisa FAPESP nº 141), besides the guidelines published in book form, helped the Department of the Environment to improve the legislation. According to the Unicamp professor, up to now, 19 legal instruments use information from Biota. “This rarely happens,” Joly said, “and the knowledge we gathered was also used for zoning the areas for planting sugarcane in the state.” Moreover, the example gave rise to similar initiatives in other states and at the federal level, having also generated partnering agreements in Latin America and Africa. The continuity of the Biota program is now guaranteed until 2020.

Even giving rise to products such as maps, the listings of species are far from being the end of the story. Some Biota projects, coordinated by Joly himself, aim to unravel the terrestrial environments that are still relatively unknown. “We need to describe the cycles of carbon, of water, and of nutrients, to understand how climate change affects ecosystems and the services they provide,” warned the botanist. He noted that the Mata Altlântica, i.e., the Atlantic Coastal Forest, occupies the largest Brazilian state capitals, such as Rio de Janeiro and São Paulo, and is home to about 125 million people. “This only leaves about 10% of the forest, and that’s where the water comes from for this entire population.” An example of the serious problems caused by the reduction of forests is the situation of water supply for the state of Rio de Janeiro, provided mostly by the Paraibuna dam, 320 km away from the state capital. “There’s no longer water any closer,” he said.

Eduardo CesarCarlos Alfredo Joly, Anita Marsaioli and Vanderlan BolzaniEduardo Cesar

To understand the workings of the Atlantic Coastal Forest, the group coordinated by Joly is studying areas at an altitude gradient ranging from sea level, in Ubatuba, up to a thousand meters, in São Luiz do Paraitinga. “We marked 21 thousand trees of 625 species,” he said. The results show that the Atlantic rainforest is very different from the Amazon forest in terms of how it stores carbon. Especially at the higher altitudes, the rainforest in the Southeast stores more soil carbon underneath than above the ground. In these mountainous areas, much of the organic matter that falls – such as twigs and leaves – breaks down slowly, because of the cold. “We walk on soft ground that is actually not soil, but peat,” he said. These regions are therefore very susceptible to climate change. With global warming, the organic material is expected to decompose faster, so that much of the carbon should be released, thereby aggravating matters.

Coming closer to chemistry, Joly said that national wealth is still unexplored, among other reasons because of the legislation, which makes working in this area feel like martyrdom, in his words. “We need to use the chemical diversity of our biodiversity, among other things as a mechanism for sustainability,” he said. One of the challenges he undertook when he accepted the position of director of the Department of Thematic Policies and (DPPT) in the Ministry of Science and Technology (MCT), is to relax the rules for research and development of new products based on biodiversity. An initiative that is indispensible to boost the Biota Bioprospecting and Bioassays, Network, a subprogram of Biota called BIOprospecTA, dedicated to finding molecules in nature that may be useful to humans.

Molecular diversity
The chemical aspect of the biota was inaugurated in 2003 by Vanderlan Bolzani. “It was the first natural products’ chemistry project in a research program into biodiversity,” she said. With her supervisor, Otto Gottlieb, a pioneer in the chemistry of natural products in Brazil, she learned that the diversity of molecules has high added value, a scientific value that can become an economic one. “A plant produces hundreds of substances and just one of them may be more important than a galaxy.” she stated, paraphrasing the master.

Many of the molecules used today in the pharmaceutical industry are synthetic, as the June conferences showed (see Pesquisa FAPESP nº 185), but chemists are inspired by biodiversity to produce these complex substances. That is why for Vanderlan it is important that this natural laboratory is maintained. An example is the Conus magus snail, which lives in the Red Sea and the Indian Ocean and from whose poison an analgesic substance a thousand times more powerful than morphine was obtained and approved for clinical use in the United States in 2004. “Two hundred years after discovering morphine, bio-prospecting in marine environments gave rise to a drug that is even more effective for treating chronic pain,” emphasized the chemist from Unesp.

She regrets that so many opportunities are being lost in Brazil. “We have a large number of species of Myrtaceae in our biodiversity” she said, referring to the family of plants that have already served as the basis for drugs in other parts of the world. Such is the case with the crimson bottlebrush (Callistemon citrinus), in which the substance nitisinone was found, which with a small modification gave rise to the treatment for a rare disease. “If we had the right environment and structure in Brazil, we’d take better advantage of the opportunities that plants offer us,” she stated; after all, there are some 55,000 vegetable species in the country’s ecosystems.

There is a success story surrounding cordia (Cordia verbenacea), which is very common on the whole of the Brazilian coast and that gave rise to the lotion Acheflan, for treating tendonitis and muscle pains. According to Vanderlan, it was the first anti-inflammatory treatment fully developed in Brazil, in a partnership between universities (the Federal University of Santa Catarina and Unicamp) and industry (Laboratório Farmacêutico Aché). The medication is made from substances that Vanderlan extracted when she was a student, but for which she had no use at the time. With the advance of knowledge, what was discarded before has now become a bestseller.

A lot of research is necessary to achieve this knowledge: substances do not come with product information and instructions on how they should be used. On the contrary, they are often toxic in their natural state. “Nature produces these molecules for their own regulation; it doesn’t produce any thinking about our health,” she pointed out. It is researchers who need to study them in order to adapt them.

Chemical nature
The diversity of the use of substances by the animals and plants that make them is the theme of chemist Anita Marsaioli, who ties chemistry to biodiversity in an even bigger way. “I don’t know how to classify plants or animals; I know how to classify chemical substances,” she said. This is why she conducts her projects in a partnership with biologists.

Such is the case of her study of opiliones, in which she is being helped by Glauco Machado from the University of São Paulo (see Pesquisa FAPESP nº 144). She said that these spiders give off “a horrible stench,” and it is this mixture of chemical defense substances that her group investigated in the context of the evolution and diversification of the group. The team mapped out the substances found in the secretion on the phylogenetic tree, the genealogical tree of the species. The analysis shows that some substances appeared at a certain point on the tree, which is a clue for investigating if anything else changed in the biology of those opiliones. The discovery is curious: the species in which new compounds appeared also spat out the defense liquid, instead of simply having droplets of it oozing from their bodies.

To discover what the substances are, how they are formed and the way they act is not easy. In this case it required that the chemists from Unicamp assemble what Anita calls an opilione hotel and synthesize substances in the laboratory. As a result they showed how the sprayed defense substance remains in the environment and releases the smell little by little over a period of five days, which scares away any predators. Now the group is ready to describe how opiliones produce these substances with no access to laboratory tricks, such as ampoules where the reaction takes place without oxygen and at 180o Celsius.

The delightful universe revealed by Anita is a real tribute to the biological and chemical variation of nature in Brazil. It involves different systems, like the chemical communication that takes place between plants of the malpighiaceae family and lone bees, and the diversity of poisons in a single species of fire ant (Solenopsis saevissima) even within the same colony (workers and queens have different compounds that may have completely different functions).

“The biodiversity is in the organisms, the enzymes and the molecules,” concludes Anita, who insists that research in the country needs to invest in the best of what it has. Given the opportunities abroad at the start of her career, she chose to tame Brazilian biodiversity. She does not regret it.

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