View metadata, citation and similar papers at core.ac.uk brought to you by CORE provided by Crossref ASEAN J. Sci. Technol. Dev., 29(2): 105 – 114 Chemical Composition of Leaf and Seed Oils of Dryobalanops aromatica Gaertn. (Dipterocarpaceae) A. S. KAMARIAH1*, T. OZEK2, B. DEMIRCI3 AND K. H. C. BASER2,3 The essential oils of the leaves and seed of Dryobalanops aromatica Gaertn. obtained by hydro- distillation resulted in 0.07% and 1.89% yield, respectively. These oils were then examined by GC-MS. Eighty-three components (plus an unknown) were identified from the leaf oil, representing 92% of the oil. Oxygenated monocyclic monoterpenes (terpinen-4-ol 15%, α-terpineol 16%), bicyclic monoterpene (α-pinene 7%) and oxygenated bicyclic sesquiterpene (globulol 8%) were the major constituents. In the case of the seed oil, 31 components were identified, representing 100% of the oil, while acyclic monoterpene (myrcene 5%), monocyclic monoterpene (limonene 6%), bicyclic monoterpenes (α-pinene 41%, α-thujene and β-pinene 13% each, sabinene 6%), and bicyclic sesquiterpene (bicyclogermacrene 6%) made up the major components. The remaining constituents of each oil (54% and 10%, respectively) were found to be minor (≤4% each). The chemical compositions of both oils differed quantitatively but showed important qualitative similarities and differences. The results of this study serve as the first report of complete chemical profiles of both oils. Key words: Dryobalanops aromatica; essential oils; leaf; seed; hydro-distillation; GC-MS; oxygenated monocyclic monoterpenes; α-terpineol; bicyclic monoterpene; oxygenated bicyclic sesquiterpene; acyclic monoterpene Dryobalanops, locally known as kapur, is a girth. The trunk is usually a straight, cylindrical genus of large and tall trees from the Family and clear bole of 30 m–40 m. This species is Dipterocarpaceae. The genus consists of a well-known and valuable timber tree. The seven species which are widely distributed timber has been described as being moderately in Sumatra, Peninsular Malaysia and Borneo hard, heavy and durable (Ashton 1964). It (Corner 1981; Ashton 2004). The four species is used as an internal wood and resembles found in Brunei Darussalam are Dryobalanops mahogany when given a good polish. It has a aromatica Gaertn, D. beccari Dyeri, D. camphor odour, and the camphor in the wood lanceolata Burck and D. rappa Becc. was sought after and sold as medicine in the past (Burkill 1966). The camphor produced by D. aromatica (Figure 1), commonly known the tree is less important today than its timber, as the Bornean Camphor-Tree, and locally but in the earlier days the reverse was the case. known as kapur peringgi, is a large and lofty The species also produces camphoraceous tree, reaching up to 65 m in height and 7 m in oleo-resin. 1 Biology Programme, Faculty of Science, Universiti Brunei Darussalam, Tungku Link Road, Bandar Seri Begawan BE 1410, Negara Brunei Darussalam 2 Department of Pharmacognosy, Faculty of Pharmacy, Anadolu University, 26470 Eskisehir, Turkey 3 Badebio Ltd., Technopark of Anadolu University, 26470 Eskisehir, Turkey * Corresponding author (e-mail: [email protected]) ASEAN Journal on Science and Technology for Development, 29(2), 2012 The uses of the wood and camphor of 35% resin (Burkill 1966, p. 881). The resin D. aromatica in both eastern and European consists mainly of triterpenes (Cheung & medicines have been well documented (Burkill Wong 1972) and the oxygenated derivatives of 1966; Perry 1980; Siang 1983; Duke & Ayensu asiatic acid as minor constituents (Cheung & 1985). The camphor has also been used by Tokes 1968). The camphor consists of borneol, the Malays and the Sumatran people in the camphor, camphene, sesquiterpenes and ceremonial purification of dead bodies and terpineol (Perry 1980, Duke & Ayensu 1985), their preservation until burial (Burkill 1966). while the wood extracts contain largely terpenes A mixture of the volatile oils of D. aromatica, and fatty acids (Ali & Koh 1991). However, Piper longum, Santalum album, Asarum an earlier distillation attempt on the leaves sieboldi and Alpinia officinarum is said to in 1910 yielded little oil and no details were be effective in the treatment of acute anginal provided (Burkill 1966, p. 881). A later attempt attack (Guo et al. 1983). The methanol extract at distilling the leaves and twigs showed that of the wood is also shown to have antifungal no oil or borneol was obtained (Eaton 1925). properties (Hong & Abdul Razak 1983; Kim Since then, there has not been any study on et al. 2005). the essential oils in the leaves of this plant. In addition, no published work can be traced with Chemical examination on the oleo-resin reference to the volatile oil of its seed. The of D. aromatica shows that it consists of 35% lack of information and details on both the leaf terpenes (including pinene), 10% alcohols and seed oils of D. aromatica prompted us to (including borneol), 20% sesquiterpenes and undertake this investigation. Figure 1. Dryobalanops aromatica Gaertn. (Bornean Camphor-Tree), a popular timber species today, was once well-known for its camphor. 106 A. S. Kamariah et al.: Chemical Composition of Leaf and Seed Oils of Dryobalanops aromatica Gaertn. Thus, the present study aims to identify and oils were collected in dark brown glass vials document fully for the first time the chemical and stored at 4°C until further analysis. The constituents present in the essential oils percentage compositions of the oils were obtained from the fresh leaves and seed of D. calculated based on the fresh weight of the aromatica. This study may allow us to identify respective plant parts. potential uses and better utilization of these plant parts which are usually discarded when the tree is harvested for its timber. Properties of Essential Oils Oil density was determined by using a piknometer, refractive index by a Shimadzu Experimental Bausch and Lomb Abbe refractometer, and Plant Material optical rotation by an Onel Pol S-2 polarimeter. Fresh leaves (Figure 2A) and seed (Figure 2B) of D. aromatica were collected from the Bukit Gas Chromatography-mass Spectrometry Sawat forest in the Belait District of Brunei (GC-MS analysis) Darussalam. The species was identified by the GC-MS analysis of the oils was carried out on author, Dr Kamariah Abu Salim and confirmed by Awang Ariffin Abdullah Kalat of the Brunei a Hewlett Packard GCD system. Separation National Herbarium (BRUN), Sg. Liang. A was performed in an Innowax fused silica voucher specimen bearing reference no. SN- capillary (FSC) column (60 m × 0.25 mm id; B000340 was deposited at BRUN. 0.25 mm film thickness). Helium at a flow rate of 1 ml min–1 was used as the carrier gas. The temperature of the GC oven was initially set at Isolation of Essential Oils 60°C for 10 min, and then increased at a rate Immediately, after collection, the fresh leaves of 4°C min–1 to 220°C. It was held isothermally and seed were subjected to hydro-distillation at 220°C for 10 min, programmed to 240°C at in a Neo-Clevenger apparatus for 4 h. The a rate of 1°C min–1, and finally maintained at Figure 2. Dryobalanops aromatica Gaertn (A) fresh leaves and (B) fresh fruit. 107 ASEAN Journal on Science and Technology for Development, 29(2), 2012 240οC for 20 min. Split injection was conducted status of the species must be considered and at a flow rate of 50 ml min-1 with a split ratio of given a priority in any attempt to exploit the 50:1. The temperature of the injector was set at seed for commercialization of the oil. It may 250οC and the ionization energy was 70 eV. The be better for the discarded seed (when present) mass range was from 35 to 425 m/z. during timber extraction to be collected for propagation and re-planting purposes. Determination of Essential Oil Composition The low percentage of oil yield from the leaves seems to be in agreement with earlier Chemical identification of the different work carried out when negligible (Burkill 1966, components of the oils was based on their p. 881) or no yield at all was obtained (Eaton retention times and comparison of their 1925). Thus, any commercial exploitation mass spectra with those of the Wiley GC- of discarded leaves for the oil during timber MS Library and a home-made library (Baser harvest needs to take into account this low Library of Essential Oil Constituents). The yield, available resources and the cost of relative percentage composition of the volatile production. compounds was calculated from the Total Ion Chromatogramme (TIC), assuming that the relative response factor was equal to 1. Chemical Composition The identified compounds in the oils of D. Results and Discussion aromatica leaves and seed, their relative amounts and their retention indices (Kovat’s Yields and General Considerations Indices for Polar Column) are shown in Table 2. The yields and physico-chemical properties of the leaf and seed oils of D. aromatica are The leaf oil contains 84 compounds shown in Table 1. representing 92 % of the total oil. α-terpineol (16%), terpinen-4-ol (15%), globulol (8%) and Although the density, refractive index α-pinene (7%) were the major constituents. The and optical rotation of both oils appear to seed oil contains 31 compounds representing show very little difference, the oil yield of 100% of the total oil, with the major the seed was significantly (twenty-nine times) constituents being α-pinene (41%), α-thujene higher than that of the leaves. Thus, the seeds and β-pinene (13% each), sabinene, limonene are a better source of oil than the leaves. and bicyclogermacrene (6% each), and myrcene However, the higher oil yield from the seed (5%).