Infections caused by protozoa of the genus Leishmania are a major worldwide health problem, with high endemicity in developing countries. The incidence of the disease has increased since the emergence of AIDS. In the absence of a vaccine, there is an urgent need for effective drugs to replace/supplement those in current use. The plant kingdom is undoubtedly valuable as a source of 11ew medicinal agents. The present work constitutes a review of the literature on plant extracts and chemically defined molecules of natural origin showing antileishmanial activity. The review refers to 10 l plants, their families, and geographical distribution, the parts utilized, the type of extract and the organism tested. It also includes 288 compounds isolated fro1n higher plants and microorganisms, classified into appropriate chemical groups. Some aspects of recent antileishmanial-activity-directed research on natural products are discussed.
Leishmaniasis is regarded as a major public health problem (WHO, 2002), causing significant morbidity and mortality in Africa, Asia and Latin America. The disease currently threatens about 350 million women, men and children in 88 countries around the world. with about 2 million affected annually. In Brazil, studies report the occurrence of about 20.000 new cases of the illness actually. An increase in the incidence of leishmaniasis can be associated with urban development, forest devastation, environmental changes and migrations of people to areas where the disease is endemic (Carvalho et al., 2000; .Patz et aJ .. 2000; Ashford, 2000).