Peruvian Plant Extracts Active Against TB, Other Diseases. A medical research team from Washington University, two Peruvian universities, and the GD Searle pharmaceutical company collaborating wiht the Aguaruna, an indigenous people of Peru, have found that extracts from more than 40% of plants identified by the Aguaruna as having healing properties were active in pharmacological assays. Searle will develop drugs from the medicinal plants under study.