Abstract
Brazil possesses great biological and cultural diversity, above all, in view of the great number of indigenous ethnic groups - 218 in all - that inhabit the five main biomas in Brazil. The purpose of this review is to analyze the relationship between chemical constituents of species utilized by several groups of Brazilian Indians and the uses/indications made of the species by these same groups using ethnopharmacological surveys by different researchers, as from the seventies. The 34 publications selected, involving 26 indigenous ethnic groups, showed a total of 307 species utilized for 67 different diseases or effects possibly related to the Central Nervous System (CNS). These plants belong to 85 taxonomic families, mostly Fabaceae, Asteraceae, Rubiaceae, Poaceae, Apocynaceae, Bignoniaceae, Euphorbiaceae, and Solanaceae. The chemical constitution of these plants was researched as from the Pubmed and Web of Science and the information obtained was crossed with different indigenous uses, grouped in 12 categories according to similarities between their expected effects on the CNS: analgesics, to counteract fever, tonics and/or adaptogens, hallucinogens, anxiolytics, anticonvulsants, head illnesses, hypnotics, stimulants, weight control, memory enhancers, and others. Some phytochemical classes were observed to be more common among plants utilized for certain purposes: flavonoids (analgesia, fever, anxiety, hypnotic, weight control, and as a stimulant), alkaloids (hallucinogens, head illnesses, and as a stimulant), essential oils (fever and anxiety), lignans (hallucinogen), tannins (anxiety), triterpenes and saponins (hypnotic). These data suggest that these phytochemical classes possibly possess a greater number of chemical constituents that perform the effects described or that, in some way, assist in determining the use of the plant by the Indians.
Keywords: Ethnopharmacology, central nervous system, plants, phytochemistry, Indians, Brazil, flavonoids, alkaloids