Amazonian ethnobotany and the search for new drugs.

Tropical rain forests offer enormous prospects for the discovery of new drugs for use in Western medicine. The Amazon supports 80,000 species of higher plants and a diverse Indian population. Focusing attention on those plants used as medicines by indigenous peoples is the most efficient way of identifying the plants that contain bioactive compounds. There is an urgent need for more ethnobotanists and ethnopharmacologists to be trained to document as much information as possible before it and the plants are lost through destruction of the rain forest and acculturation of the indigenous peoples. Ethnobotanical studies have identified plants documented by early travellers; these include Paullinia yoco and Ilex guayusa which are used as stimulants and have been shown to be rich in caffeine. Studies of the hallucinogen prepared from Banisterioposis caapi have shown that the native people know which plants to add to the mixture to lengthen and intensify the intoxication produced by the beta-carboline alkaloids in the plant. Three major snuffs are used in the Amazonia; the plants from which they are derived have been identified. One of the snuffs also has antifungal and curare-like activities; chemical analysis on the active principles has not been done. Several plants are considered as prime candidates for scientific study as sources of useful chemicals for medicine or industry. These include some used to prepare teas or other infusions for treatment of various symptoms of senile dementia.

Plants in treating senile dementia in the northwest Amazon.

The Indians of the northwest Amazon respect age and try to care for those suffering from senile dementia. At least 25 species of plants are employed in treating Alzheimer's disease or similar problems. The plants are administered orally as teas of the leaves or roots and over a period of several days to numerous weeks. The plants are from 15 phanerogamic families. Little chemistry is known of most of the species. In view of the current interest in Alzheimer's disease and related problems these species might profitably be investigated.

Virola: a promising genus for ethnopharmacological investigation.

Data are now available on the antifungal use of Virola from four countries and some 14 different tribes of Indians in these countries who employ the Virola exudate for the same or similar purposes. Three of the five methods of ethnobotanical investigation proposed by Schultes and Swain in 1976 have been employed in this ethnobotanical research. Furthermore, both of the present authors have successfully employed this antifungal treatment themselves. Given that deep fungal infections of the skin are often considered incurable with medications currently in use, further laboratory analysis of Virola resin should be undertaken as soon as possible.

De plantis toxicariis e mundo novo tropicale commentationes. XXXIV: Biodynamic rubiaceous plants of the northwest Amazon.

This paper continues ethnopharmacological notes on biodynamic plants employed by Indians of the Amazon region as medicines, poisons or narcotics.

De plantis toxicariis e mundo novo tropicale commentationes. XXXV: Miscellaneous notes on biodynamic plants of the northwest Amazon.

This paper continues ethnopharmacological notes on biodynamic plants employed by Indians of the Amazon region as medicines, poisons or narcotics.

Fifteen years of study of psychoactive snuffs of South America: 1967-1982--a review.

Much has been learned concerning psychoactive snuffs in South America in the past 15 years since I delivered a review paper in the now famous symposium "Ethnopharmacologic Search for Psychoactive Drugs" held in San Francisco in 1967 (Efron et al., 1967; Schultes, 1967). There is still much to be investigated, but it seems that a recapitulation at this time may be warranted. The advances in our knowledge have come about as a result of field work as well as laboratory research and have been effected by investigators in several disciplines: archaeology, ethnobotany, ethnology and phytochemistry.

Jaborandi: an interdisciplinary appraisal.

In spite of many references to Pilocarpus Jaborandi Holmes in ethnological and botanical sources and suggestions of its employment for a variety of diseases, it has not been possible to pin down the use of its leaves to any particular purpose amongst South American Indians. While the medically important jaborandis are species of Pilocarpus, it is true that this vernacular name is commonly applied to other rutaceous and numerous piperaceous plants as well. The introduction of jaborandi leaves to western medicine goes back to 1873, when Symphronio Coutinho went to Europe, taking with him samples of the leaves. The copious sweating and salivation brought about by the leaves attracted the attention of French physicians. Soon jaborandi leaves were being employed in the treatment of many diseases. In 1875, Hardy and Gerrard independently discovered the alkaloid pilocarpine. Most therapeutic applications of jaborandi leaves and pilocarpine fell into disuse and were discontinued. What remained was the use of the latter in ophthalmology, where it had been introduced as a miotic by Weber in 1876. The mixture of pilocarpine and another natural product, physostigmine, remains to this day one of the mainstays in ophthalmology.