View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Elsevier - Publisher Connector South African Journal of Botany 2003, 69(3): 301–363 Copyright © NISC Pty Ltd Printed in South Africa — All rights reserved SOUTH AFRICAN JOURNAL OF BOTANY ISSN 0254–6299 Bark medicines used in traditional healthcare in KwaZulu-Natal, South Africa: An inventory OM Grace1, HDV Prendergast2, AK Jäger3 and J van Staden1* 1 Research Centre for Plant Growth and Development, School of Botany and Zoology, University of Natal Pietermaritzburg, Private Bag X01, Scottsville 3209, South Africa 2 Centre for Economic Botany, Royal Botanic Gardens, Kew, Richmond, Surrey TW9 3AE, United Kingdom 3 Department of Medicinal Chemistry, Royal Danish School of Pharmacy, 2 Universitetsparken, 2100 Copenhagen 0, Denmark * Corresponding author, e-mail: [email protected] Received 13 June 2002, accepted in revised form 14 March 2003 Bark is an important source of medicine in South Overlapping vernacular names recorded in the literature African traditional healthcare but is poorly documented. indicated that it may be unreliable in local plant identifi- From thorough surveys of the popular ethnobotanical cations. Most (43%) bark medicines were documented literature, and other less widely available sources, 174 for the treatment of internal ailments. Sixteen percent of species (spanning 108 genera and 50 families) used for species were classed in threatened conservation cate- their bark in KwaZulu-Natal, were inventoried. gories, but conservation and management data were Vernacular names, morphological and phytochemical limited or absent from a further 62%. There is a need for properties, usage and conservation data were captured research and specialist publications to address the in a database that aimed to synthesise published infor- gaps in existing knowledge of medicinal bark species mation of such species. Data specificity was found to be and their management to conserve the South African the major limiting factor in the study and resulted in flora. uneven distribution of information in the database. Introduction Accounts of plants used traditionally assist not only in the ex may provide the substrate on which subsequent studies are situ conservation of indigenous culture, knowledge and based. belief systems (Rajan et al. 2001), but also in channelling South Africa has a long history of research in economic research towards useful plant species. The ethnobotanical botany that focussed on plants with agricultural potential, approach to plant research highlights that those species and on weed control (Wickens 1990). More recently, the used traditionally are most likely to yield useful products and economic potential of South African medicinal plants has are most likely to be threatened by over-exploitation. been recognised. In contrast, ethnobotanical or anthropo- Furthermore, indigenous knowledge is recognised as valu- logical studies of people–plant interactions in this country able in reducing environmental degradation and promoting are relatively few. The single and therefore definitive chroni- sustainable utilisation (Cunningham 1988, Hedberg 1993, cle of the Zulu pharmacopoeia is that of Hutchings et al. De Beer 2000, Okoji 2001). Understanding the dynamics of (1996) and of the southern African region, Watt and Breyer- people–plant interactions may facilitate important contribu- Brandwijk (1962). Recent ethnobotanical inventories of tions to the management of flora where it is most relied upon South African medicinal plants include those of Hutchings (Cunningham 2000, Williams et al. 2000). An inventory of (1989a, 1989b), Scott-Shaw (1990), Williams et al. (2000, locally important plant species can be invaluable in this 2001) and Botha et al. (2001), as well as economic studies process of understanding. In the case of medicinal flora, by authors such as Cunningham (1988), Mander et al. demands, species used and their popularity, can reflect (1997) and Mander (1998). regional differences in the health needs of local users Barks comprise nearly one third of the medicinal plant (Williams et al. 2000). The role of the inventory therefore products traded and used in South African traditional health- extends beyond a simple list of plants, vernacular names care (Mander 1998, Williams 1996), which is consulted by and usage. Although inventories have been criticised for not the majority of the population (Cunningham 1988). The being sufficiently scientific (Cunningham 2000, Botha et al. importance of bark in meeting the healthcare needs of South 2001), the information contained in a local plant checklist Africans is not reflected by the ethnobotanical literature 302 Grace, Prendergast, Jäger and Van Staden (reviewed by Grace et al. 2002a). There is a need for com- persists in many accounts of traditional medicine (Elvin- prehensive sources of information to empower efforts of Lewis and Lewis 1995), including many consulted for this conservation, trade monitoring and healthcare standardisa- review. Preconceived values and beliefs superimposed tion. upon evaluations of traditional medicine systems may also influence the information accounted (Iwu 1993). Accordingly, Material and Methods the TADWG (International Working Group on Taxonomic Databases for Plant Sciences) standard for recording plant A comprehensive literature survey was undertaken to con- uses (Cook 1995) was employed to implement acceptable solidate existing knowledge of the uses, properties and con- terminology where possible. servation status of plant species used medicinally for their Morphological and phytochemical descriptors of each bark in KwaZulu-Natal, South Africa. It was intended that a species’ bark were compiled. Although integral to any cata- single source of information, dealing specifically with eth- logue of plant species (WHO, IUCN and WWF 1993), illus- nomedicinal barks, would be generated from the most pop- trations, distributions, habitat and cultivation data that are ular and widely available literature that forms the basis of well documented in existing accounts were excluded. Notes ethnobotanical studies in South Africa. The literature was on conservation status were made, to highlight a taxon’s assessed in terms of the usefulness of recorded information, value. Trade information was considered pertinent, including and how it may be translated to the conservation of medici- data from outside KwaZulu-Natal, since much of the materi- nal bark species. al traded throughout South Africa is harvested or supplied by Plant species used medicinally for their stem- and/or root- markets in KwaZulu-Natal. Data outside other data fields bark in KwaZulu-Natal, South Africa were identified in litera- were included as additional notes. ture surveys. A Microsoft® Access 2000© database was designed to accommodate searchable data fields detailing Results and Discussion bark usage and properties for each taxon. Sensitive param- eters were set to ensure that data referred explicitly to the Literature medicinal purpose or properties of bark used in KwaZulu- Natal (although they may occur and be used elsewhere); The limiting factors affecting this inventory were the lack of this selective approach aimed to ensure quality rather than literature dealing specifically with bark, and, where barks are quantity of information in the database. Data collected from explicitly mentioned, vague information: omitting to detail diverse media were entered into several categories: vernac- user populations, localities, correct botanical nomenclature, ular plant names used in KwaZulu-Natal; usage in the sources of plant material, or methods of medicinal prepara- province and southern Africa; field descriptions and bio- tion. Forty-two books were consulted, 15 conference pro- chemical properties of the bark; conservation status of each ceedings or investigative reports, 72 papers in refereed jour- species; and miscellaneous notes. Rather than a numeric nals, and three flora or memoir publications. ‘Grey’ sources, reference system, sources were cited in the text. Species so-called due to usually obscure locality and troublesome entries from the database are presented here (Appendix 1), accessibility, included three magazine articles and anecdot- ordered alphabetically rather than by taxonomic relation- al knowledge attributed to personal communications. ships, for ease of reference. Several grey sources, identified in electronic searches or Botanical nomenclature was taken mostly from Arnold and cited in other publications, could not be accessed. De Wet (1993), Mabberley (1997) and Wiersama and León Cunningham (2000) recommended that, to overcome the (1999). Authors of scientific names were abbreviated problem of valuable data being obscured in grey literature, according to Brummit and Powell (1992). With reference to copies should be deposited in recognised libraries and pub- the three dominant languages in the province, common lished in international journals. Publication on the Internet English, Afrikaans and Zulu names were taken from the lit- may also facilitate access to such literature. In this invento- erature, including Von Breitenbach et al. (2001). Zulu nouns ry, emphasis was placed on consolidating data contained are characterised by a prefix and stem that are sometimes within the most popular and widely consulted sources, rather denoted by a hyphen and/or capitalised stem. For example, than comprehensive literature reviews of each taxon. the common Zulu name for Acacia