Notobubon galbanum is an evergreen shrub, renowned for causing severe blistering of human skin when touched. It is also well known as a Cape medicinal plant.
Notobubon galbanum is a woody evergreen shrub, up to 2.5 m high. Leaves arranged along the upper parts of the branches, compound; leaflets ± rhomboidal, toothed and sometimes 3-lobed, green above and glaucous below. Flowers small, yellow, borne in large, rounded compound umbels on a relatively short peduncle. Fruit dry, dorsally flattened with narrow wings along the margins.
Flowering time: October–February
Least Concern (LC)
Distribution and habitat
Widespread in moist fynbos vegetation from Elands Bay to the Cape Peninsula and east to the Langeberg Mountains in the Western Cape Province of South Africa.
Derivation of name and historical aspects
The species of Notobubon were previously placed within the large predominantly Eurasian genus Peucedanum L. However, recent studies of the African Peucedanum species (Winter et al. 2008) revealed that they were not related to their supposed Eurasian relatives and were therefore separated into six African endemic genera, namely Afroligusticum C.Norman, Afrosciadium P.J.D.Winter, Cynorhiza Eckl. & Zeyh., Lefebvrea A.Rich., Nanobubon Magee, and Notobubon B.E-van Wyk. The twelve currently recognized species of Notobubon can be distinguished from the previously mentioned African genera by the shrubby habit, the permanent woody branches, the evergreen leathery leaves and the smaller fruit.
The root of the name Notobubon, reflects the fact that many of the species of this genus were once part of the genus Bubon L. (see e.g. Sonder 1862).The Greek prefix “ noto ” means southern and alludes to the genus's southern African origin (Magee et al. 2009). The specific epithet, “ galbanum ” indicates that at the time of its description this species was erroneously considered to be the species from which one of the oldest recorded medicines, galbanum, was obtained.
The flowers of Notobubon galbanum attract a wide range of insect visitors and the plant is also a host to the citrus swallowtail, Papilio demodocus (Kroon, 1999). Notobubon galbanum is probably best known for causing severe blistering of human skin, hence the common name blisterbush (Smith 1966). This phototoxic condition manifests only several hours after contact with the leaves (Van Wyk et al . 2002) and is due to a reaction, in the presence of sunlight (ultraviolet light), between the furanocoumarins of the plant and the DNA of the skin. As mentioned by Marloth (1925) the blistering effect of N. galbanum is quite variable. This variation may depend on the extent of tissue damage to the plant (i.e. from herbivores), as well as the degree of exposure of the affected skin to sunlight subsequently. The fruits are also unusual in that the seed is surrounded by an almost continuous ring of oil canals, called vittae (indicated by arrows in the figure below, which shows a fruit in transverse section). These canals contain phenolic compounds, including coumarins, and probably serve to protect the nutrient-rich seed from insect damage.
Uses and cultural aspects
Notobubon galbanum is a well-known Cape medicinal plant whose ethnobotanical uses have been well documented (Dykman 1891; Kling 1923; Marloth 1925; Pappe 1857; Rood 1994; Van Wyk et al. 1997; Watt & Breyer-Brandwijk 1962). It has been recorded primarily as a remedy for rheumatism, gout, bladder ailments, water retention and high blood pressure. Pappe (1857), a medical doctor interested in plants, recorded “wilde seldery” as being “reputed amongst the inhabitants as an excellent diuretic”, while Dykman (1891), in her South African recipe book, recommends a brandy tincture of the leaves for treating obesity in men. Watt & Breyer-Brandwijk (1962) record that it is also used as a diuretic, in combination with Diosma hirsuta L. for dropsy and renal diseases, or with Mentha longifolia Huds. and Pelargonium grossularioides (L.) L'Hér. for suppression of the menses. Van Wyk et al. (1997) add that an infusion together with Chironia spp. is used as a remedy against rheumatism.
Growing Notobubon galbanum
Specific i nformation regarding the cultivation of N. galbanum is currently unavailable. However, those described by Forrester (2006) for Peucedanum polyactinum B.L.Burtt [now Notobubon capense (Eckl. & Zeyh.) Magee] are likely to be applicable to this species as well. The plant is probably best placed in sun or semi-shade, near the back of the herbaceous bed. Due to the phototoxicity of the leaves care should be taken to plant it in an area where unnecessary contact with the leaves is minimized, and of course also while handling it during planting. The bold leathery discolorous leaves and structurally striking, large compound umbels make this shrub an appealing garden subject.
References and further reading
- Dykman, E.J. 1891. Kook-, Koek- en Resepte Boek. Paarl: Paarlse Drukpers Maatskappy.
- Forrester, J. 2006-08. Peucedanum polyactinum B.L.Burtt. Internet 4 pp. http://www.plantzafrica.com/plantnop/peucedpoly.htm.
- Kling, H. 1923. Die Sieketrooster. Van de Sandt, de Villiers and Co., Cape Town.
- Kroon, D.M. 1999. Lepidoptera of Southern Africa. Host-plants and other associations. A catalogue. Lepidopterists' Society of Africa, South Africa.
- Magee, A.R., Van Wyk, B.-E. & Tilney, P.M. 2009. A taxonomic revision of the woody South African genus Notobubon (Apiaceae: Apioideae). Systematic Botany 34: 220–242.
- Marloth, R. 1925. The flora of South Africa : with synoptical tables of the genera of the higher plants 2. Darter Bros. and Co., Cape Town.
- Pappe, L. 1857. Florae capensis medicae prodromus,. edn 2. Cape Town.
- Rood, B. 1994. Uit die veldapteek. Tafelberg, Cape Town.
- Smith, C.A. 1966. Common names of South African plants. Memoirs of the Botanical Survey of South Africa 35. Department of Agricultural Technical Services, Pretoria.
- Sonder, O.W. 1862. Umbelliferae. Flora Capensis 2: 524–567. Harvey, W.H. & Sonder, O.W. (eds). Hodges Smith, Dublin.
- Van Wyk, B.-E., Van Oudtshoorn, B. & Gericke, N. 1997. Medicinal plants of South Africa. Briza Publications, Pretoria.
- Van Wyk, B.-E., Van Heerden, F. & Van Oudtshoorn, B. 2002. Poisonous plants of South Africa. Briza Publications, Pretoria.
- Watt, J.M. & Breyer-Brandwijk, M.G. 1962. The medicinal and poisonous plants of Southern and Eastern Africa, edn 2. Livingstone, London.
- Winter, P.J.D., Magee, A.R., Phephu, N., Tilney, P.M., Downie, S.R. & Van Wyk, B.-E. 2008. A new generic classification for African peucedanoid species (Apiaceae). Taxon 57 (2): 347–364.
Anthony R. Magee