Humboldt and Bonpland

Curare was obtained from several sources but most commonly from the vine Chondrodenron tomentosiim. The explorers Humboldt and Bonpland in South America (1799-1804) reported that an extract of its bark was concentrated as a tar-like mass and used to coat arrows. The potency was designated one tree if a monkey, struck by a coated arrow, could only make one leap before dying. A more dilute ( three tree ) from was used to paralyse animals so that they could be captured alive - an early example of a dose-response relationship. 

Humboldt and Bonpland, who collected Datura sanguinea on the banks of the Rio Mayo, in New Granada, state that the natives believe that the tonga prepared from this species to be more efficacious as a narcotic than that made from the white-flowered Datura arborea mentioned above. It is from the account of these travelers that the story of the Peruvian prophets is taken. The Temple of the Sun in which they officiated was at Sagamoza, in the interior of what is now Colombia. Dr. Santiago Cortes, in his account of the medicinal plants of the province of Cauca, Colombia, says that there are many stories and fables relating to this plant told by the natives. 

Since Humboldt and Bonpland first saw the preparation of curare, there have been many descriptions, some more detailed than others, of the procedures used by the Indians. Inevitably, there is considerable variation in the methods, but they all have in common extraction of the plant material that provides the active principles, followed by concentration of the extract depending on their supposed properties, other ingredients may be added before the extraction is carried out or added as such, or as an extract, in the course of the concentration phase. Several methods of preparation are described below and they make clear, when the sensitivity of the active principles to the effects of heat, light, air, and pH is taken into account, why Stryc/mos-based curares contain such highly complex mixtures of alkaloids. See further Sections 1.4.2 and 1.4.3. 

An alkaloid of a less familiar type, containing isovoacangine and hydrocanthine components, is bonafousine (252), the major alkaloid of a genus not previously investigated, Bonafousia tetrastachya (Humboldt, Bonpland, and Kunth) Markgraf. The structure was determined by the X-ray method, and the absolute configuration from the c.d. spectrum of its O-methyl ether. 

Humboldt, A. von and A Bonpland (Translation and editing by T. Ross) 1S52-1853. PersonalNarrative of Travels to the Equinoctial Re nsofAmerica. Henry G. Bohn, London, England. 

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