Tabebuia

Pereira, E.M. et al., Tabebuia avellanedae naphthoquinones activity against methi-cillin-resistant staphylococcal strains, cytotoxic activity and in vivo dermal irritability analysis, Ann. Clin. Microbiol. Antimicrob., 22, 5, 2006. 

Latin American lapacho tree, Pau d Arco Tabebuia spp., Bigncmiaceae, Ang.), an Andean traditional tea... 

Methyl, 2-hydroxymethyl-, and 2-formylanthraquinones in the heart wood of teak (Tectona grandis, Verbenaceae) are effective in inhibiting termite activity (105). Several naphthoquinone derivatives including lapachol are thought to impart marine borer resistance to woods, e.q. that of Tabebuia quayacan (Bignoniaceae) (108). 

Wood and cell cultures of Catalpa ovata [88-89], wood of Haplophragma adenophyllum [90], Tabebuia guayacan [91] T. pentaphylla [83], Zeyhera tuberculosa [92] Roots of Ekmanianthe longiflora (all Bignoniaceae) [78], Biological Effect inhibition of topoisomerase II [16]. 

OH 0 0 Wood of Tabebuia impetiginosa [112], Kigelia pinnata [93], Crescendo cujete [107-108]). Roots of Ekmanianthe longiflora [78] (all Bignoniaceae). Biological effect antitumoral [78] [107]. 

Roots of Tabebuia cassinoides (Bignoniaceae) [110]. Biological effect antitumoral [78]. 

The naphthoquinones with acid hydroxyl function like lapachol are easily extracted with bases. They are also extracted in a Soxhlet apparatus with EtOH, and the resulting extract is then exhaustively extracted with AcOEt to yield a residue rich in naphthoquinones [115-116]. The naphthoquinones are mainly isolated from the wood and heartwood but there some examples of isolation from the roots [46, 48, 53, 58, 65, 66, 75, 78]. The study of commercial herbal products sold as Taheebo, Pau d Arco, Lapacho, and Ipe roxo carried out by Girard et al [117], showed important differences in the content of lapachol and other related naphthoquinones present in extracts of Tabebuia ssp Tabebuia rosea, T. cassinoides, T. impetiginosa, and T. chrisantha. Similar works using HPLC techniques have been carried out by Awang et al. [118]. 

Oxidation product of polyhydroxyphenolic Gallic acid Haplophragma adenophyllum, Phyllarthron comorense [wood], Tabebuia avellanedae [wood] (Bignoniaceae), Tectona grandis (Verbenaceae) [root]... 

Lapachol (95, from the lapacho tree, genus Tabebuia, family of the catalpa trees, Bignoniaceae) and its analogues show very broad therapeutic capabilities , including activity against cancer which results in apoptosis and inhibition in metastasis, antimicrobial, antifungal, antimalarial and other activities . However, clinical application of lapachol is limited by its high toxicity. Lapachol forms complexes with many metal ions. 

Immune system Immune deficiency (immune stimulant) Tabebuia avellanedeae Lor. ex Griseb and other species (Bignoniaceae) Uncaria tomentosa D.C., U. guianensis J.F. Gmel. (Rubiaceae) inner bark inner bark... 

Mutagenesis and Neonlasias Inhibitors of mutagenesis or of cancer Tabebuia spp. (see Immune stimulation above) Copaifera spp (see Skin diseases below) Himatanthus sucuuba (Spruce) Woodson (Apocynaceae) inner bark trunk oil latex... 

Figure 2 Lapachol occurs in the heartwood of many Tabebuia species. Its interfence in oxidative processes has been documented. Its metabolite fi-lapachone inhibits enzymes associated with DNA replication. However the use of Tabebuia bark (pau d arco) as a cancer preventative can hardly be attributed to these activities.

Among other compounds from Kigelia pimata, kigelinone (85) was isolated (81P2271). A related compound, 86, was proposed for one of the cytotoxic compounds isolated from the bark of Tabebuia cassinoides. Two other compounds isolated from K. pimata are 87 and 88, and the structure of the latter was confirmed by synthesis (82MI4). 

Lapachol, an alcohol that can be converted into P-lapachone (21), a prenyl-naphto-l,2-quinone known for its anti-tumoral, pro-apoptopic and topoisomerase I-inhibitory properties was obtained from the lapacho tree, Tabebuia avellanadae (Bignoniaceae). Although an inhibition of PTKs has not, to our knowledge, been reported, P-lapachone inhibited the activation of INK and MEK by tumour necrosis factor (TNF). These effects may account for the observed inhibition of the NF-KB-mediated gene expression and the mentioned biological activity [71],... 

Lewis, W., Okunade, A., and Elvin-Lewis, M. 2004a. Pau d Arco or Lapacho (Tabebuia) . Marcel Dekker. 

Roots of Ekmanianthe longiflora [78] roots of Zeyhera montana [37] Kigelia pinnata [93] roots of Tectona grandis (Verbenaceae) [46] roots and leaves of Newbouldia laevis [94-95] wood of Tabebuia palmeri [96] wood of T. chrysotricha [97] wood of T. serratifolia [98] heartwood of Tecomella undulatum [99] heartwood of Dolichandrone crispa [100] heartwood of T. avellanedae [101]. 

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