Essential Oils of Chaerophyllum macropodum Boiss. and Chaerophyllum crinitum Boiss. from Iran

Abstract

The water-distilled essential oils from aerial parts of Chaerophyllum macropodum Boiss. and Chaerophyllum crinitum Boiss. were analyzed by GC and GC/MS. The oil of C. macropodum was found to contain α-pinene (23.0%), β-pinene (17.3%) and fenchyl acetate (13.8%) as the major constituents. The oil of C. crinitum was characterized by a higher amount of (E)-β-ocimene (50.5%). Both oils were richer in monoterpene than sesquiterpene hydrocarbons.

Key Word Index

Chaerophyllum macropodum, Chaerophyllum crinitum, Umbelliferae, essential oil composition, α-pinene, β-pinene, fenchyl acetate, (E)-β-ocimene.

Introduction

The genus Chaerophyllum is comprised of about 110 species, eight are described in the flora of Iran, among which two are endemic: C. nivale Hedge et Lamond and C. khorassanicum Czern. ex Scliischk. (1,2). A few reports on the analysis of the essential oils of Chaerophyllum species have been published (3-9). A literature survey revealed that the oils of C. macropodum and C. crinitum have not been previously studied, so we decided to examine these oils.

Experimental

Plant material: The aerial parts of Chaerophyllum species were collected in around Chalous road, 120 km north of Tehran, Iran, in June 2001, during the flowering stage. Voucher specimens have been deposited at the Herbarium of the Research Institute of Forests and Rangelands (TARI), Tehran, Iran.

oil isolation: The air-dried parts of C. macropodum and C. crinitum were subjected to separate hydrodistillation using a Clevenger-type apparatus for 3 h. After decanting and drying of the oils over anhydrous sodium sulfate, the corresponding oils were isolated in yield of 0.1% and 0.5% (w/w), respectively.

Analysis: GC analysis was performed on a Shimadzu 15 A gas Chromatograph equipped with a split/splitless injector (250°C) and aflame ionization detector (250°C). N2 was used as carrier gas ( 1 mL/min) and the capillary column used was DB-5 (50 m × 0.2 mm, film thickness 0.32 µm). The column temperature was kept at 60°C for 3 min and then heated to 220°C with a 5°C/min rate and kept constant at 220°C for 5 min.

GC/MS analysis was performed using a Hewlett Packard 5973 with an HP-5MS column (30 m × 0.25 mm, film thickness 0.25 µm). The column temperature was kept at 60°C for 3 min and programmed to 220°C at a rate of 5°C/min and kept constant at 220°C for 5 min. The flow rate of helium as carrier gas was 1 mL/min. MS were taken at 70 eV.

Identification of the constituents of each oil was made by comparison of their mass spectra and retention indices (RI) with those given in the literature and those authentic samples (10). Relative percentage amounts were calculated from peak area using a Shimadzu C-R4A chromatopac without the use of correction factors.

Results and Discussion

The composition of the oils of C. macropodum and C. crinitum are listed in Table I, in which the percentage and retention indices of components are given. As it is shown, about 98.5% (28 components) of the oil C. macropodum and 84.3% (11 components) of the oil of C. crinitum were identified. The oil of C. macropodum consisted mainly of 11 monoterpene hydrocarbons (71.0%), eight oxygenated monoterpenes (20.2%), seven sesquiterpenes (6.8%), and two aliphatic esters (0.5%).

α-Pinene (23.0%), β-pinene (17.3%) and fenchyl acetate ( 13.8% ) were the major components in this oil, followed by (Z)-β-ocimene (8.6%), (E)-β-ocimene (6.5%), limonene (6.3%) and myrcene (5.5%) and three oxygenated monoterpenes (2.4%). The major component of this oil was (E)-β-ocimene (50.5%) followed by β-phellandrene (8.8%), p-cymene (7.1%) and γ-terpinene (6.5%) As can be seen from the above information, both oils were rich monoterpene hydrocarbons (71.0% and 81.9%, respectively).

Previous investigation on oils of the Chaerophyllum genus showed varying compositions. The dominant compound in the oil of C. bulbosum, growing in Azerbaijan, was linalool (18%) (4). Of the oils isolated from the leaves and stems collected during the vegetative and the flowering phases of the plant and from the fruits of C. azoricum, growing in Azores archipelago, terpinolene (44-62%) and γ-terpinene (9-31%) were the main oil components (6). Essential oils of ripe fruits and umbels of C. coloratum, growing in Montenegro, contained high percentages of (E)-β-farnesene (79.2% and 68.4%, respectively) (7). The oil of C. aksekiense, growing in Turkey, contained heptacosane (10.1%), humulene epoxide II (7.8%), (E)-β-farnesene (6.2%) and caryophllene oxide (6.0%) as major components (8).

A water-distilled oil obtained from the aerial parts of C. macrospermum has been the subject of our previous study. The major components were identified to be (E)-β-ocimene (40.0%), tricyclene (19.4%) and δ-3-carene (18.3%) (9).

Acknowledgment

We are grateful of V. Mozaffarian (Research Institute of Forests and Rangelands, Tehran) for helpful assistance in botanical identification.

References

1. K.H. Rechinger, Chaerophyllum. In: Flora lranica, Umbelliferae. No. 162, Edits., K.H. Rechinger and I.C. Hedge, pp. 89, 92, Akademische Druck and Verlagsanstalt, Graz, Austria (1987).