Abstracts

Essential Oils of Camphor Tree (Cinnamomum camphora Nees & Eberm) Cultivated in Southern Brazil

Caren D. Frizzo¹, Ana C. Santos¹, Natalia Paroul¹, Luciana A. Serafini¹, Eduardo Dellacassa², Daniel Lorenzo² and Patrick Moyna^* * Author for correspondence

¹Instituto de Biotecnologia, UCS, 95001-970, Caxias do Sul, RS; Brazil;²Cátedra de Farmacognosia y Productos Naturales, Facultad de Química, UR , 11800, Montevideo, Uruguay

ABSTRACT

The essential oils of two varieties of Camphor tree (Cinnamomum camphora Nees & Eberm, Lauraceae), known as Hon-Sho and Ho-Sho cultivated in experimental stands in Southern Brazil were studied. The essential oils were obtained from the leaves and twigs of young plants by hydrodistillation. The identification of the components was performed using GC, GC/MS and retention indexes on methyl silicone and carbowax phases. The main components identified were linalool in the Ho-Sho and camphor in the Hon-Sho.

Key Words: Cinnamomum camphora; leaves; essential oils; GC/MS; linalool; camphor.

INTRODUCTION

Camphor tree (Cinnamomum camphora Nees & Eberm, Lauraceae) essential oils have been extensively studied (Guenther,1950). The tree is native to China, Formosa and Japan (Yoshida et al., 1969). The traditional oils are obtained from the wood and bark (Stahl, 1957; Dung and Khien, 1991; Pandey et al., 1997). The oil with a high content of camphor has an important antifungal activity (Takaoka et al., 1976; Sattar et al., 1991).

C. camphora has several chemical varieties which have different essential oil compositions (Hattori, 1981; Huergo et al., 1978; Lin et al., 1994; Akeng´a et al., 1994; Moellenbeck et al., 1997; Dung et al., 1993). Two varieties have been exploited commercially, Hon-Sho (C. camphora Nees & Eberm.), the most valuable for the presence of camphor, and Ho-Sho (C. camphora Nees & Eberm var. linaloolifera Fujita) for it high content of linalool. These varieties are morphologically similar, but they show different essential oil compositions and for this reason are considerated physiological varieties (Guenther, 1950).

The oils obtained from the leaves by steam distillation have economic importance as their main components are camphor and linalool (Guenther, 1950), and their explotation is less detrimental to the trees . The compositions of the essential oils from aerial parts have been reported by many authors (Fujita et al., 1974; Pellisier et al., 1995; Stahl, 1957).

MATERIALS AND METHODS

Plant material.The aerial parts of young plants of Camphor tree (C. camphora Nees & Eberm and C. camphora Nees & Eberm var linaloolifera Fujita) were collected in May 1998 at the Experimental Farm of the Instituto de Biotecnologia of the Universidade de Caxias do Sul, Brazil. The specimens were identified and deposited at the Herbarium of the Museu de História Natural of the Universidade de Caxias do Sul (C. camphora Nees & Eberm, Hon-sho,Voucher Nº HUCS 12.892 and C. camphora Nees & Eberm var. linaloolifera Fujita, Ho-sho, Voucher Nº HUCS 12.891).

Essential oil.The essential oil was obtained with a yield of 0.84% (w/w) to the Ho-Sho and 0.72 % (w/w) to the Hon-Sho from the aerial parts, by a 1 hour hydrodistillation in a Clevenger-type apparatus, and dried over anhydrous Na₂SO₄.

Analytical.GC analysis were performed on a Hewlett Packard 6890 Series, equipped with a HP-Chemstation data processor, in two columns. The first was a HP-5 bonded phase capillary column (30 m x 320 µm i.d.), 0.25 m m film thickness (Hewlett Packard, Palo Alto, USA); FID detector; column temperature, 60° C (8min) to 180° C at 3° C/min, 180-230° C at 20° C/min, 230° C (20min.); injector temperature 250° C ; split ratio 1:50; detector temperature 275° C; carrier gas H₂ (32 kPa), volume injected 0.1 µL.

The second was a HP-Innowax bonded phase capillary column (30 m x 320 µm i.d.), 0.50 µm film thickness (Hewlett Packard, Palo Alto, USA), column temperature, 40° C (8min.) to 180° C at 3° C/min, 180-230° C at 20° C/min, 230° C (20min.); injector temperature 250° C ; split ratio 1:50; detector temperature 250° C;carrier gas H₂ (34 kPa), volume injected 0.1 µL.

GC-MS analysis were conducted using a Shimadzu QP 5050 equipped with Adams library, using two capillary columns. The first was a fused silica capillary column, (25 m x 250 µm i.d.), stationary phase SE-52, 0.25 µm film thickness (Mega, Legnano, Italy) ; column temperature, 60ºC (8 min) to 180ºC at 3ºC/min, 180-230ºC at 20ºC/min, injector temperature 250ºC; split ratio 1 :40 ; volume injected, 0.2 µL of the oil. He gas was used as a carrier, using 122.2 kPa (51.6 mL/min); interface temperature 250ºC ; detector 1.15 kV ; acquisition mass range 40-400 ; solvent cut, 2 min.

The second was a fused silica capillary column, (25 m x 250 µm i.d.), stationary phase BP-20, 0.25 µm film thickness (SGE, Australia); column temperature, 40ºC (8 min) to 180ºC at 3ºC/min, 180-230ºC at 20ºC/min. injector temperature 250ºC ; split ratio 1 :40 ; volume injected, 0.2 µL of the oil. Carrier gas was He, 92.6 kPa (55.9 mL/min); interface temperature 250ºC ; detector 1.10 KV ; acquisition mass range 40-400 ; solvent cut, 2 min.

The constituents of the oil were identified by the combination of mass spectral and retention indexes and they were compared with both those of reference authentic compounds and from library spectra data and literature (Adams, 1995; Jennings and Shibamoto, 1980) and are reported in Tables 1 (Hon-sho) and ² (Ho-sho).

RESULTS AND DISCUSSION

The Hon-Sho leaf oil obtained in Caxias do Sul showed 31 components. 94% of the composition is made by monoterpenes and 2% by sesquiterpenes. Oxygenated terpenes represented 81% of the total, camphor being the main component (68%) and linalool the second most important (9%).

The camphor content was similar to that described for Pakistan (Sattar et al., 1991) and Ivory Coast (Pelissier et al. 1995) leaf oils.

The Ho-Sho leaf oil was almost exclusively formed by linalool (95%), with no other constituent representing more than 1%. In this the product is similar to the most common compositions described in the literature (Lin and Hua, 1987; Tao et al., 1987; Fujita et al. , 1974; Dung et al., 1993), where linalool content varied from 66 to 91%. Contents of cineol and nerolidol described for cetain samples (Lin and Hua, 1987; Nguyen et al., 1994) could not be confirmed in Brazilian samples.

ACKNOWLEDGEMENTS

The authors would like to thank the support of CNPq (Conselho Nacional de Desenvolvimento Científico e Tecnológico, Brazil), SCT/RS (Secretaria de Ciência e Tecnologia do Estado do Rio Grande do Sul, Brazil), the Istituto Italo Latino Americano (Ministero per gli Affari Esteri, Direzione Generale per la Cooperazione e lo Sviluppo, Italia) and the International Foundation for Science (grant F/2196-2). The help of Prof.Dr. N. Frighetto (Unicamp, SP) in the acquisition of the seeds of both plants is acknowledged with thanks.

RESUMO

Os óleos essenciais de duas variedades da árvore canforeira (Cinnamomum camphora Nees & Eberm, Lauraceae), conhecidas como Hon-Sho e Ho-Sho cultivadas em canteiros experimentais no sul do Brasil foram estudados. Os óleos essenciais foram obtidos das folhas e ramos de plantas jovens por hidrodestilação. A identificação dos componentes foi feita por GC, GC/MS e índices de retenção nas fases metil silicone e carbowax. Os principais componentes foram linalol no Ho-Sho e cânfora no Hon-Sho.

Received: March 19, 1999;

Revised: May 10, 1999;

Accepted: October 01, 1999.

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