Composition of the Essential Oil from Laserpitium gallicum. Grown in the Wild in Southern France

Abstract

The essential oils of Laserpitium gallicum. L. (Apiaceae) from two sites in southern France have been analyzed. In plants from one site, α.- and β.-pinene were the main components, whereas the samples from the second site displayed approximately equal amounts of α.-pinene, β.-pinene, sabinene, and limonene. Additionally, some oxygenated monoterpenes, sesquiterpene hydrocarbons, and oxygenated sesquiterpenoids could be found. The leaf oil had a composition similar to the fruit oil.

Keywords:

• Apiaceae
• essential oil composition
• Laserpitium gallicum
• myrcene
• α-pinene
• β-pinene
• sabinene

Introduction

Laserpitium gallicum. L. (Apiaceae) is a perennial calcicolous plant up to 120 cm tall with pinnate leaves, cuneiform leaflets, and winged fruits growing in the mountains of southern Europe on dry and stony sites in open vegetation. Although it is a conspicuous aromatic plant, the volatile components have barely been studied. A first work signalized α.- and β.-pinene and small amounts of limonene and p.-cymene (Adcock & Betts, 1974). A more recent study of the essential oil of the fruits has been carried out by Kubeczka (2003) and confirmed these findings. As essential oils often present certain variability, the current study reports the oil composition of L. gallicum. from two locations in southern France.

Materials and methods

Plant material

The plants came from two sites in southern France and were collected in July 1999 and August 2001, respectively, when the major umbells had fully developed fruits. The sites were (1) Département Alpes de Haute Provence (slopes with open shrub vegetation over limestone, ca. 3 km west of Rougon near Castellane, 1050 m), and (2) Département Alpes Maritimes (Steep, rocky slope over Road D21, ca. 5 km north of Lucéram, 850 m).

The Flora Europea. (Tutin et al., 1968) and the Flore de France. (Guinochet & Vilmorin, 1975) were used for identifying the plants. Voucher specimens were deposited in the herbarium of the University of Vienna (WU-Generale, http://herbarium.univie.ac.at), with the numbers 37892 (inflorescences) and 37893 (leaves) for the site Rougon and 37894 (inflorescences) and 37895 (leaves) for the site Lucéram. The airdried plant material was stored at room temperature and distilled within 3 months.

Hydrodistillation

The plant parts (25 g) were subjected to hydrodistillation for 2 h in a Clevenger-type apparatus containing 250 mL of double distilled water. The essential oil was stored at − 18°C until GC/MS analysis.

GC/MS

Prior to analysis, 5 µL of the oil was diluted with 1000 µL ethyl acetate. To record the pattern of volatile components in the extracts or in the oil, a HP 6890 GC was equipped with a 5972 quadrupole mass selective detector. The separation was done on a 30 m × 0.25 mm fused silica column coated with 0.25 µm HP5-MS. The analytical conditions were carrier gas He 1.3 mL/min, constant flow; injector temperature, 250°C; split ratio, 15:1; temperature program, 2 min at 40°C, with 3°C/min up to 180°C. The injector temperature was set at 250°C, and the injection volume was 1 µL. The compounds were identified according their mass spectra and their retention indices (McLafferty, 1989; Adams, 2001). The total ion current (m/z. 40 to 350) has been used to calculate the relative amounts of the volatile components.

Results and Discussion

As presented in Table 1, in the oil, the monoterpene hydrocarbons prevailed. α.-Pinene and β.-Pinene were the main oil components in the fruits from Lucéram, whereas in the samples from Rougon, besides the two pinenes, remarkable amounts of sabinene and myrcene could be found. In this case, fruits and leaves displayed comparable compositions. Further minor compound present in plants of both origins were limonene, trans.-pinocarveol, pinocarvone, and myrtenal. Additionally, terpinen-4-ol and α.-thujene were minor compounds in the fruits and leaves from Rougon. Sesquiterpene hydrocarbons and oxygenated sesquiterpenoids made up less than 3% of the essential oil.

Table 1.. Composition of the essential oil of Laserpitium gallicum.

			Rougon
	RI	Luceram fruits	Fruits	Leaves
Oil yield (%v/w)		0.7
Hexanal	804		0.2	0.1
Heptanal	906			0.1
α.-Thujene	933		0.6	3.2
α.-Pinene	940	28.5	17.0	20.1
Camphene	953	1.0	0.6	0.8
Verbenene	959	0.1	0.3	0.2
Sabinene	981		17.2	10.4
β.-Pinene	983	38.5	14.8	24.0
Dehydro-1,8-cineole	988	0.1
Myrcene	994	2.6	11.8	14.6
Octanal	1007		0.2	0.2
α.-Terpinene	1022		1.0	0.2
p-Cymene	1028	0.4	0.9	0.6
Limonene	1033	5.5	3.4	4.8
γ.-Terpinene	1063	0.1	1.8	0.4
cis.-Sabinene hydrate	1074		0.7	0.1
Terpinolene	1093		0.6	0.2
trans.-Sabinene hydrate	1105		1.0
Perillene	1105			0.4
α.-Campholene aldehyde	1131	0.6	1.3	0.4
Nopinone	1133	0.1
trans.-Pinocarveol	1135	2.8	2.4	1.1
cis.-Verbenol	1140	0.3
trans.-Verbenol	1154		1.6
Citronellal	1155	0.8
Nonen-al^a.	1166		0.6	0.7
Pinocarvone	1168	2.6	2.0	0.2
p-Mentha-1,.5-dien-8-ol	1175		0.6
Terpinen-4-ol	1182	0.2	3.8	0.4
α.-Terpineol	1188	0.2	0.2
Myrtenal	1191	3.7	3.2	2.0
Myrtenol	1193	2.2
Decanal	1209		0.2	0.1
trans.-Piperitol	1214		0.1
Verbenone	1214	0.3	0.3	0.1
trans.-Carveol	1222	0.1	0.2
Citronellol	1232	1.0	0.2
Cuminal	1243	0.2	0.2
Carvone	1247	0.2	0.1
Phellandral	1284		0.2
Bornyl acetate	1289	1.2	0.2	0.3
(E,E.)-2,4-Decadienal	1323		0.1
α. -Terpinyl acetate	1357			1.2
α.-Copaene	1379	0.2	0.2	0.1
β.-Cubebene	1386	0.1
β.-Bourbonene	1392		0.3
β.-Elemene	1397			0.2
Dodecanal	1411	0.1	0.2	0.2
β.-Caryophyllene	1420	0.1		0.7
α.-Humulene	1462			0.1
α.-Amorphene	1484		0.1
Germacrene D	1484	0.4	0.2	0.5
β.-Selinene	1489	0.1	0.1	0.4
Bicyclogermacrene	1504			0.2
δ-Cadinene	1514			0.2
Germacrene B	1567		0.0
Spathulenol	1583	1.1	1.5	0.8
Caryophyllene oxide	1588	0.3	0.6	1.1
Humulene epoxide*	1620			0.2
β.-Eudesmol	1645	0.3		0.7
α.-Eudesmol	1648	0.2

RI, retention index.

^a.Correct isomer not identified.

A fruit oil of L. gallicum. from southern France displayed α.- and β.-pinene as main compounds and lower amounts of limonene and sabinene (Kubeczka, 2003) and had, therefore, a comparable composition as the sample from Lucéram reported here. Kubeczka (2003) pointed out also a small fraction of sesquiterpenes and even numbered fatty acids. These fatty acids, however, could not be found in the current study.

The composition of the essential oil of L. gallicum. clearly differed from the oils of other Laserpitium. species. The water-distilled oil from the aerial parts of Laserpitium petrophilum. Boiss. et Heldr., a species endemic in Turkey, displayed α.-pinene and sabinene as prevailing components (Baser & Duman, 1997). In the leaves and fruits of Laserpitium latifolium. from Austria, sabinene was the main compound of the oil followed by α.-pinene and limonene (Chizzola & Novak, 1999). More than 90% in the fruit oil of Laserpitium siler. L. from southern France was composed of perilladehyde and limonene (Chizzola et al., 1999).