GuacoMikania glomerata

Did you know?

• The sweet smell of guaco leaves comes from coumarin, the same fragrant compound that gives new-mown hay its scent and is found in tonka beans^{[6, 7, 9, 10]}.

• In Brazil, "guaco" means two look-alike vines, M. glomerata and M. laevigata. They are so similar that they are often mistaken for each other^{[5, 6, 7]}.

• Guaco syrup is one of the herbal preparations that Brazil's public health system provides free of charge^{[6, 8]}.

• Mikania glomerata was one of the plants in the very first Brazilian Pharmacopoeia, in 1929^[4].

• Guaco's genus, Mikania, is large: Kew recognizes about 450 species^[13].

• Mikania guaco was named in 1811 by Aimé Bonpland, in Plantae Aequinoctiales, a work he published with Alexander von Humboldt^{[2, 3]}.

Origins and history

Guaco is a vigorous climbing vine, or liana, with twining stems^{[5, 7]}. It grows in the Atlantic Forest along Brazil's coast, from Bahia in the northeast to the southern states, at forest edges and in the forest itself, and its native range reaches Paraguay and northern Argentina^{[1, 4, 7]}. Its leaves are aromatic, and botanists note the characteristic smell of coumarin as one of the features shared by the two Brazilian guacos^{[6, 7]}.

The Brazilian guaco was given its scientific name, Mikania glomerata, by the botanist Kurt Sprengel^{[1, 3]}, but guaco is a shared name. In Brazil it belongs to two close relatives, M. glomerata and M. laevigata, which are so alike that they are often confused^{[4, 5, 6, 7]}. Farther north and west, from Mexico and Central America to the Amazon, Peru and Bolivia, the name goes with a third species, M. guaco^{[2, 3]}. That vine was described in 1811 by Aimé Bonpland in Plantae Aequinoctiales, the botanical work he published with Alexander von Humboldt^{[2, 3]}.

In Brazil the leaves are made into syrups, tinctures and other liquid preparations, and guaco syrup is widely used today^{[4, 6, 8]}. M. glomerata is listed in the Brazilian Pharmacopoeia, the country's official book of standards, and guaco preparations are handed out free through Brazil's public health programs^{[4, 5, 6, 8]}.

Traditional uses

Clinical studies of guaco in people are still few^{[6, 8]}, but its traditional use in Brazil is long and well documented^{[4, 5, 11]}.

• Guaco syrup

  Guaco leaves are made into a sweet syrup, the preparation for which the plant is best known in Brazil.^{[4, 6, 8]}

• Respiratory health

  For centuries, guaco has been a Brazilian herb for the chest and airways. Guaco supports respiratory health.*^{[4, 5, 7]}

• Tinctures and extracts

  Guaco leaf is also prepared as a tincture and as a liquid extract.^[8]

Plant compounds

Guaco leaves contain coumarin, a fragrant plant compound that is used as guaco's chemical marker, the compound measured to check its quality^{[4, 8]}. Coumarin is joined by other, related coumarins^{[6, 7]}, by kaurenoic acid^{[6, 8]} and by chlorogenic acid^[4].