South African Journal of Botany 76 (2010) 652 – 654 www.elsevier.com/locate/sajb
Chemical composition of the wood and leaf oils from the “Clanwilliam Cedar” (Widdringtonia cedarbergensis J.A. Marsh): A critically endangered species G.P.P. Kamatou a , A.M. Viljoen a,⁎, T. Özek b , K.H.C. Başer b a
Department of Pharmaceutical Sciences, Faculty of Science, Tshwane University of Technology, Private Bag X680, Pretoria 0001, South Africa b Department of Pharmacognosy, Faculty of Pharmacy, Anadolu University, 26470-Eskişehir, Turkey Received 15 February 2010; received in revised form 31 March 2010; accepted 1 April 2010
Abstract Widdringtonia is the only genus of the 16 genera of Cupressaceae present in South Africa. This genus is represented by three species in South Africa; W. nodiflora, W. schwarzii and W. cedarbergensis (= W. juniperoides) and the latter listed as critically endangered. Cedarwood oil (generally obtained from Juniperus species) is widely used as a fragrance material in several consumer products, however, no data has been published on the volatiles of the Clanwilliam cedar (W. cedarbergensis) native to South Africa. The essential oil composition of the wood and leaf oil isolated by hydro-distillation were analysed by GC–MS. The two oils were distinctly different. Twenty compounds representing 93.8% of the total oil were identified in the leaf oil which was dominated by terpinen-4-ol (36.0%), sabinene (19.2%), γ-terpinene (10.4%), α-terpinene (5.5%) and myrcene (5.5%). Twenty six compounds representing 89.5% of the total were identified in the wood oil with the predominance of thujopsene (47.1%), α-cedrol (10.7%), widdrol (8.5%) and cuparene (4.0%). © 2010 SAAB. Published by Elsevier B.V. All rights reserved. Keywords: Essential oil; Sabinene; Terpinen-4-ol; Thujopsene; Widdringtonia cedarbergensis; Widdrol; α-Cedrol; γ-Terpinene
1. Introduction The genus Widdringtonia belongs to the Cupressaceae (cypress family) of which the name is derived from the well known conifer botanist Edward Widdrington. The cypress family is represented by 16 genera with one genus (Widdringtonia) present in southern Africa more precisely in South Africa and Malawi (Farjon, 2005). There are four species of Widdringtonia, all native to southern Africa. Three of these species are native to South Africa (W. nodiflora, W. schwarzii and W. cedarbergensis) and Widdringtonia whytei is native to Malawi. Widdringtonia cedarbergensis J.A. Marsh generally known as “Clanwilliam
⁎ Corresponding author. Tel.: +27 12 3826360; fax: +27 12 3826243. E-mail address: email@example.com (A.M. Viljoen).
Cedar, Cape Cedar, sederboom or Clanwilliam cypress” is an evergreen tree usually 5–7 m tall but could reach a height of 20 m (Fig. 1). Today, this plant is critically endangered due to loss of habitat, unsustainable harvesting and recurrent veld fires. This species is facing an extremely high risk of extinction in the wild and for this reason it has been placed on the Red Data List of South African Plants (Farjon, 2005; Mustart et al., 1995; Pauw and Linder, 1997). The tree is renowned for its valuable timber and used for construction and furniture and has been used to treat several ailments such as gout, rheumatism, oedematous swellings. The heartwood of Widdringtonia cedarbergensis is pungently aromatic and produces oil which may have various applications. However, the chemical composition of this oil has not been investigated. Cedarwood oil produced by various species is used as an exclusive ingredient in several consumer products. While Texas cedarwood is mostly used as feedstock for the production of some compounds such as cedrol, cedryl
0254-6299/$ - see front matter © 2010 SAAB. Published by Elsevier B.V. All rights reserved. doi:10.1016/j.sajb.2010.04.002
G.P.P. Kamatou et al. / South African Journal of Botany 76 (2010) 652–654
Fig. 1. The Clanwilliam cedar in habitat....