Searching for new drugs by milling through ancient folk pharmacopoeia or by just picking a plant while walking in the woods has a decidedly checkered history. Many well-established therapeutic compounds originated in trees, shrubs, mollusks, even dirt. Aspirin came from willow bark, cholesterol-lowering statins from a mold, and the antimalarial artemisinin from a shrub used in traditional Chinese medicine. Yet after raising $90 million during the 1990s in a much publicized bid to tap indigenous knowledge for new drug leads, Shaman Pharmaceuticals had to lower its sights until it was doing nothing more than selling its products as nutritional supplements before finally shutting its doors for good a few years ago.

Now the trend may be reversing itself again. Recently a number of natural compounds--such as resveratrol from red wine and omega-3 fatty acids from fish oil--have begun to receive close scrutiny because preliminary research suggests they might treat and prevent disease inexpensively with few side effects. Turmeric, an orange-yellow powder from an Asian plant, Curcuma longa, has joined this list. No longer is it just an ingredient in vindaloos and tandooris that, since ancient times, has flavored food and prevented spoilage.