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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
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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
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