Volatile Constituents from the Oil of Trigonella foenum-graecum L.

Volatile Constituents from the Oil of Trigonella foenum-graecum L.

Ahmadiani, Abolhassan

Abstract

The essential oil of the aerial parts of Trigonella foenum-graecum has been studied by means of GC and GC/MS. The main components of the oil were found to be [delta]-cadinene (27.6%), [alpha]-cadinol (12.1%), [gamma]-eudesmol (11.2%) and [alpha]-bisabolol (10.5%).

Key Word Index

Trigonella foenum-graecum, Leguminosae, essential oil composition, [delta]-cadinene, [alpha]-cadinol, [gamma]-eudesmol, [alpha]-bisabolol.

Plant Name

Trigonella foenum-graecum L., Leguminosae.

Source

Plant material was collected in june 1999 during its flowering stage from Kalateh, Ebrahim-Shah, 25 km north of Bodjnourd province of Khorassan. A voucher specimen has been deposited in the Herbarium of the Department of Botany, Shaheed Beheshti University, Tehran, Iran.

Plant Part

Fresh aerial parts (15Og) of the flowering plant were water distilled for 3 h using a Clevenger-type apparatus to produce a light yellow oil in 0.3% yield.

Previous Work

Fenugreek (Trigonellafoenum-graecum) is an annual herbaceous member of the legume family. For many years the extract of fenugreek has been used as an ingredient for flavors, and to a lesser extent, fragrance compositions. Fenugreek extracts are generally prepared by initially extracting the ground seed with alcohol or aqueous alcoholic solutions.

Numerous types of fenugreek extracts are available. Most of the differences between the extracts relate to the timed heat treatment of the seed up to roasting temperatures prior to extraction (1). Trigonellafoenum-graecum has been used as an anthelmintic against most common nematodes. It has also been used in Indian folk medicine as an antipyretic, diuretic and supporative, and for treatment of dropsy, heart disease, chronic cough and spleen and liver enlargement (2).

The seeds of fenugreek (T. foenum-graecum) are traditionally assumed to have restorative properties. It has recently been shown that a fenugreek seed extract containing steroid saponins and flavonoids, increased food consumption and induced hypocholesterolaemia in rats. This study aimed to investigate the specific role of purified steroid saponins (furostanol-type) in these properties (3,4). Due to its content of sapogenins, particularly diosgenin, fenugreek seed is a potential future source of sapogenins for the manufacture of steroid hormones and related drugs (5).

Various sterols and flavonoids were also isolated from the leaves ofT.foenum-graecum (6). Examination of the chemical composition of the headspace of fenugreek seeds and comparison of this to a steam distillation and an extract of the same material has been reported (7).

A fraction with typical flavor was obtained by solvent-extraction and preparative chromatography of ground fenugreek seeds (T! foenum-graecum L.). Based on gas and thin-layer chromatography and gas chromatography/mass spectrometry, the dominant and characteristic compound of the fraction was identified as 3-hydroxy-4,5-dimethyl-2 (SH)-furanone (8).

In this paper, we report the composition of the essential oil of the plant obtained by hydrodistillation for the first time.

Present Work

GC analysis of the oil was carried out using a Hewlett Packard 439 with a CP SiI 5CB column (25 m × 0.25 mm, film thickness 0.39 (µm), temperature programmed as follows: 60°-220°C at 5°C/min. The carrier gas was nitrogen (0.8 mL/min); injector and detector temperatures were 270°C.

GC/MS analysis was performed using a Varian 3700 with a CP SiI 5CB column (25 m × 0.25 mm, film thickness 0.39 µm) combined with Varian M AT 44S, temperature programmed as above. The carrier gas was helium. The oil constituents were identified by matching their mass spectra with library spectra and by comparison of their retentions indices with those of standard compounds (5). Relative percentage amounts were calculated from TIC data by the computer. The identified constituents can be seen in Table I.

Acknowledgement

The authors are grateful to P. Weyerstahl, Institute of Organic Chemistry, Technical University of Berlin, for the GC/MS spectra.

References

1. B. M. Lawrence, Progress in essential oils. Perfum. Flavor., 12(5), 54-62 (1987).

2. M. Bhatti, M. Khan, B. Ahmed, M. Jamshaid and W. Ahmad, Antibacterial activityofTrigonella foenum-graecum seeds.Fritoletapia, 67,372-374(1996).

3. R.N. Chopra, S.L. Nayyarand I.e. Chopra, Glossary of Indian Medicinal Plants, 1st edn., p. 248, CSIR, New Delhi (1956).

4. K.G. Rajesh, CJ. Dharamand ST. Raghunath, Furostanolglycosidesfrom Trigonella foenum-graecum seeds. Phytochemistry, 23,2603-2607 (1984).

5. A.Y. Leung, Encyclopedia of common natural ingredients used in food drugs and cosmetics, pp. 171-173. Wiley-lnterscience, J. Wiley and Son, New York (1980).

6. A. Sood, Chemical compounds from the leaves of Trigonella foenumgraecum Linn. Indian J. Pharm., 37, 100-101 (1975).

7. P. Girardon, J.M. Bessiere, J.C. Baccou and Y. Sauvaire, Volatile constituents of fenugreek seeds. Planta Med., 533-534 (1985).

8. P. Girardon, Y. Sauvaire, U.C. Baccou and J.M. Bessiere, Identification de Ia 3-hydroxy-4,5-dimethyl-2 (SH)-furanone dans L’arome des graines de Fenugrec (Trigonella foenum-graecum L,). Lebensm.- Wiss. Tech nol., 19,44-46(1989).

9. R.P. Adams, Identification of essential oil components by gas chromatography/massspectroscopy. Allured Publ. Corp., Carol Stream, IL, USA (1995).

Abolhassan Ahmadiani

Department of Pharmacology, Shaheed Beheshti University of Medical Sciences, Tehran, Iran

Abdolhossein Rustaiyan*

Department of Chemistry, Islamic Azad University, North Tehran Branch, Tehran, Iran

Mahmonir Karimian and Mohammad Kamalinejad

Department of Pharmacognosy, School of Pharmacy, Shaheed Beheshti University of Medical Sciences, Tehran, Iran

* Address for correspondence

1041-2905/04/0004-0356$6.00/0-© 2004 Allured Publishing Corp.

Received: February 2001

Revised: November 2001

Accepted: December 2001

Copyright Allured Publishing Corporation Jul/Aug 2004

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