| Tabebuia impetiginosa | |
|---|---|
| Tabebuia impetiginosa flowering in Corrientes, Argentina. | |
| Conservation status | |
|
Not evaluated (IUCN 3.1)
|
|
| Scientific classification | |
| Kingdom: | Plantae |
| (unranked): | Angiosperms |
| (unranked): | Eudicots |
| (unranked): | Asterids |
| Order: | Lamiales |
| Family: | Bignoniaceae |
| Tribe: | Tecomeae |
| Genus: | Tabebuia |
| Species: | T. impetiginosa |
| Binomial name | |
| Tabebuia impetiginosa (Mart. ex DC.) Standl. |
|
| Synonyms | |
|
Handroanthus avellanedae (Lor. ex Griseb.) Mattos |
|
Tabebuia impetiginosa[1], Pink Ipê or Pink Lapacho is a native Bignoniaceae tree of America, distributed from northern Mexico south to northern Argentina. It is a common tree in Argentina's northeastern region, as well as in southeastern Bolivia. It is said to be indigenous to Trinidad and Tobago.
It is a conspicuous and well-known species with a long history of human use. Consequently it has a range of local names ipê-cavatã, ipê-comum, ipê-reto, ipê-rosa, ipê-roxo-damata, lapacho negro, pau d'arco-roxo, peúva or piúva. The timber is sometimes traded as "brazilwood", which properly refers to the unrelated Pernambuco Tree (Caesalpinia echinata).
Contents |
The Pink Lapacho is a rather large deciduous tree, with trunks sometimes reaching 8 dm width and 30 m height. Usually a third of that height is trunk, and two thirds are its longer branches. It has a large, globous, but often sparse canopy. The tree has a slow growth rate. Leaves are opposite and petiolate, 2 to 3 inches long, elliptic and lanceolate, with lightly serrated margins and pinnate venation. The leaves are palmately compound with usually 5 leaflets.
Its bark is brownish grey, tough and hard to peel. The wood is of a pleasant yellowish colour, barely knotted and very tough and heavy (0,935 kg/dm³). It's rich in tannins and therefore very resistant to weather and sun[2]. It is not very useful for furniture since it is so hard to work by hand. It can be found as beams or fulfilling other structural uses where needed outdoors.
Pink Lapacho flowers between July and September, before the new leaves appear. In India, the flowering season is December to January, after the leaves are shed. The flower is large, tubular shaped, its corolla is often pink or magenta, though exceptionally seen white, about 2 inches long. There are 4 stamens and a staminode. The fruit consists of a narrow dehiscent capsule containing several winged seeds.
The flowers are easily accessible to pollinators. Some hummingbirds - e.g. Black Jacobin (Florisuga fusca) and Black-throated Mango (Anthracothorax nigricollis) - seem to prefer them over the flowers of other Tabebuia species, while for others like the Stripe-breasted Starthroat (Heliomaster squamosus) it may even be a mainstay food source.[3]
Tabebuia impetiginosa, as well as other species of this genus, are trees naturally found in the wild of central to South American forests. It is also used as a honey plant, and widely planted as ornamental tree in landscaping gardens, public squares and boulevards due to its impressive and colorful appearance as it flowers[2]. Well-known and popular, it is the national tree of Paraguay. It is also planted as a street tree in cities of India, like in Bangalore.
The inner bark of Tabebuia impetiginosa is used medicinally[4]. It is dried, shredded, and then boiled, making a bitter brownish-colored tea known as Lapacho or Taheebo. The unpleasant taste of the extract is lessened when taken in pill form, or as tinctures. Lapacho bark is typically used during flu and cold season and for easing smoker's cough. It apparently works by promoting the lungs to expectorate and free deeply embedded mucus and contaminates during the first three to ten days of treatment[2].
One study has shown that recurrence of anal condylomata after surgical treatment is reduced by an admixture of the plants Echinacea, Uncaria, Tabebuja (sic), papaya, grapefruit and Andrographis.[5]
In ethnomedicine Lapacho plays an important role for several South American indigenous peoples. In the past decades it has been used by herbalists as a general tonic, immunostimulant[6] and adaptogen. About the 1980s, its was touted as having "almost unbelievable properties" and said to improve quality of life for cancer and immunodepressed patients[7]
However, the main active compound lapachol has since turned out to be toxic enough to kill fetuses in pregnant rats and reduce the weight of the seminal vesicle in male rats in doses of 100 mg/kg of body weight[8]. Still, lapachol has strong antibiotic and disinfectant properties, and may be better suited for topical applications. Lapachol induces clastogenic effects in rats.[9] Beta-lapachone has a direct cytotoxic effect and the loss of telomerase activity in leukemia cells in viro.[10]
Note that ethnomedical use of Lapacho and other Tabebuia teas is usually short-term, to get rid of acute ailments, and not as a general tonic[2]. Usefulness as a short-term antimicrobial and disinfecting expectorant, e.g. against PCP in AIDS patients, is yet to be scientifically studied. Tabebuia Impetiginosa inner bark seems to have anti Helicobacter pylori activity.[11] and has some effects on other human intestinal bacteria.[12]