Disease Protection from Green-skinned Fruit Trees

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Two new reports from the 2000 International Chemical Congress of Pacific Basin Societies reveal the power of green-skinned fruit trees at slowing or combating certain illnesses. Hirokazu Kawagishi and Kimio Sugiyama from Shizuoka University announced yesterday that potent chemicals within the avocado actually reduce liver damage. They made the discovery after feeding 22 different kinds of fruits to rats with livers injured by galactosamine. Based on changes in the levels of specific liver enzymes in the animals, the avocado appeared most able to slow the progression of injury. Next they tested five compounds from the avocado in rats with chemically induced liver damage, and found it had the same effect. Because the damage in these animals resembled that done by viruses in people, the researchers hope that avocado extracts may lead to new drugs for treating hepatitis C.

Other chemists from the University of Santo Tomas in the Philippines described compounds in the Hawaiian noni plant, Morinda citrifolia, that kill the bacterium causing tuberculosis. This group too screened a group of plants, finding that extracts from noni leaves killed 89 percent of Mycobacterium tuberculosis organisms exposed. They further discovered that the active ingredients were phytosterols, or plant steroids. Because these steroids are structurally very different from current TB drugs, they could open up an entirely new approach to treatment. "I hope that pharmaceutical companies will pay attention to this research and explore the noni plant as a potential source of drugs," says lead researcher Jonel Saludes. In the meantime, you may want to eat more guacamole.

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