Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
MEDICINAL PLANTS Indigenous South African Medicinal Plants Part 10: Heteropyxis natalensis (‘Lavender tree’) Sandy van Vuuren (PhD), Department of Pharmacy and Pharmacology, University of the Witwatersrand and Alvaro Viljoen (PhD), Department of Pharmaceutical Sciences, Tshwane University of Technology Botany: The family Heteropyxidaceae has only three representatives in southern Africa; Heteropyxis canescens, H dehniae and H natalensis. The most noteworthy is Heteropyxis natalensis, a deciduous tree growing to approximately ten metres in height. It has strongly aromatic foliage, a branched trunk and a pale-green bark, which has a distinctive mottled appearance. The leaves are small, simple, narrow, oblong/elliptic and are arranged spirally. They are pale-green on the underside with a shiny dark-green upper. The leaves may appear red-tinged when the tree is young.1 The leaves have a strong lavender odour, which is emitted in the summer; hence the vernacular name “lavender tree”. The flowers are yellowish-green, inconspicuous and are in bloom between December and March. They are usually followed by small, oval, dry capsules (fruit), which appear between March and May. The genus name is derived from Greek “Hetero”- meaning different, and a Latin “-pyxis” meaning “the container with the lid”. The latter refers to the fruit (capsule), which is sometimes called the pyxidium.2 Heteropyxis natalensis grows naturally in the northeastern part of South Africa, on the coastal and inland regions extending from the tree’s place of origin, which is KwaZulu-Natal, through to Mpumalanga, northern Gauteng regions and Northern Province. Traditional uses: Heteropyxis natalensis is used traditionally to treat respiratory disorders, as a decongestant and as an anti-infectant.1 The leaves are mainly used for medicinal purposes and prepared as a tea.3 A deconcoction of the roots is prepared and the steam inhaled for bleeding gums. Both roots and leaves have been used for bleeding disorders including nose bleeds and menorrhagia. Both the Venda and Zulu communities have reported on the medicinal value of H natalensis. The 46 powdered bark is used as an aphrodisiac.4 Scientific studies: Seasonal variation studies,5,6 on Zimbabwean H natalensis reported that the major essential oil constituents varied between plants from the same geographical region. Furthermore the phytoconstituents and antimicrobial properties as determined by the disc diffusion method of H natalensis growing in Zimbabwe has also been reported.7 Geographical and seasonal variation studies on South African H natalensis phytoconstituents indicated similar chemical profiles with fluctuation in the levels of the two major constituents (1,8cineole and limonene).8 Little variation between the antimicrobial activity of seasonally collected samples was documented. The chemogeographical variation of the oil composition from five of the seven distinct localities studied indicated little antimicrobial variability between localities (standard deviation of ± 0.5 to ± 3.8) with one oil sample, (Lagalametse), being distinctly different both chemically and microbiologically. Cryptococcus neoformans displayed the highest antimicrobial sensitivity (0.5–2.0 mg/ ml). Promising anti-inflammatory activity has also been recorded in the 5-lipoxygenase assay.9 References: 1. Van Wyk, B-E., et al., 1997. Medicinal Plants of South Africa. Briza publications, Pretoria, South Africa. 2. Venter, F. & Venter, J-A., 2002. Making The Most of Indigenous Trees. Briza publications, Pretoria, South Africa. 3. Van Wyk, B-E. & Gericke, N., 2000. Peoples Plants. A Guide to Useful Plants of Southern Africa. 1st Edition, Briza publications, Pretoria, South Africa. 4. Watt, J.M. & Breyer-Brandwijk, M.G., 1962. The Medicinal and Poisonous Plants of Southern and Eastern Africa. 2nd Edition, Livingstone, London, UK. 5. Weyerstahl, P. et al., 1992. Constituents of the essential oil of Heteropyxis natalensis. J. Essent. Oil Res. 4, 439-445. 6. Chagonda, L.S. et al., 2000. Essential oils of cultivated Heteropyxis natalensis (Harv.) and cultivated Heteromorpha trifoliata (Wendl.) Eckl. & Zey. from Zimbabwe. J. Essent. Oil Res. 12, 317-321. 7. Gundidza, M. et al., 1993. The essential oil from Heteropyxis natalensis Harv: Its antimicrobial activities and Phytoconstituents. J. Sci Food Agr. 63, 361-364. 8. Van Vuuren, S.F. et al., 2007. Seasonal and geographical variation of Heteropyxis natalensis essential oil and the effect thereof on the antimicrobial activity. S. Afr. J. Bot. 73, 441-448. 9. Frum, Y. & Viljoen A.M., 2006. In vitro 5lipoxygenase activity of three indigenous South African aromatic plants used in traditional healing and the stereospecific activity of limonene in the 5-lipoxygenase assay. J. Essent. Oil Res. 18, 8588. Heteropyxis natalensis leaves with small inconspicuous flowers The geographical distribution (orange) of H natalensis in southern Africa SA Pharmaceutical Journal – July 2008 SA Pharmaceutical Journal – July 2008 47