A spreading shade tree that is common along roadsides in India has been found to contain a collection of amazing chemicals that offer hope of new pharmaceuticals and "new era" of powerful, non-polluting pesticides, scientists believe.
Villagers in India have for centuries believed in nearly miraculous healing and insect repelling properties in the tree, known as the "neem" tree.Now, says a committee of the National Academy of Sciences, it appears the villagers were right. The traditionally cautious academy titled the new report "Neem: A Tree for Solving Global Problems."
The neem tree is a living chemical factory. Its leaves and olive-shaped fruit contain powerful, biodegradable substances that repel insects and disrupt their development, other materials that have anti-fungal, anti-bacterial and even anti-viral properties and still others that offer promise as birth control agents.
Soap and a decay-preventing toothpaste are produced from oil extracted from the seeds.
So far, the tree's most dramatic promise seems to be in the chemicals it has evolved to protect itself from insects. Though these non-polluting substances have nothing in common chemically with synthetic pesticides, their effect has been found comparable to malathion, DDT, Dieldrin and others, the committee said.
To obtain neem pesticides, farmers in the underdeveloped world do not need sophisticated chemical plants, the committee said. They only need to soak seeds and leaves in water and alcohol, then scoop off the oil that rises to the top of the mixture.
"This is one of the most fascinating things I've ever run into in my career as a scientist," said Eugene B. Shultz, an engineering professor at Washington University in St. Louis and chairman of the National Academy committee. "What this has taught me is we don't pay enough attention to traditional techniques and tend to dismiss them."