Available online 4 March 2015
Open Access
Original article
- a Laboratoire des Substances Naturelles (LR10 INRAP02), Institut National de Recherche et d’Analyse Physico-chimique, Pôle Technologique, Sidi Thabet, 2020 Ariana, Tunisia
- b Laboratoire des Venins et Biomolécules Thérapeutiques, Institut Pasteur de Tunis, 13, Place Pasteur, 1002 Tunis Belvédère, Tunisia
- c Faculté de Médecine de Tunis, La Rabta, 1007 Tunis, Tunisia
- d Centre de Recherche en Oncologie Biologique et Oncopharmacologie (CRO2), INSERM UMR 911, Faculté de Pharmacie, Marseille, France
- e Aix-Marseille Université, Marseille, France
- f Faculté des Sciences de Tunis, Campus Universitaire, Tunis El Manar, 1000 Tunis, Tunisia
- Received 19 April 2013, Accepted 24 February 2015, Available online 4 March 2015
- Open Access funded by King Saud University
- Under a Creative Commons license
Abstract
In this work the physicochemical characteristics including fatty acids, tocopherols and sterols composition of Ecballium elaterium
(L.) A. Rich seed oil was determined. Results showed that linoleic acid
(48.64%) and punicic acid (22.38%) were the major polyunsaturated fatty
acids. Among the phytosterols, β-sitosterol was the most abundant
(396.25 mg/100 g), while the major tocopherol form was γ-tocopherol
(44.23 mg/100 g). In addition, we evaluated for the first time the
effect of E. elaterium seed oil on the growth of human colonic
adenocarcinoma (HT29) and fibrosarcoma (HT1080) cell lines. The original
finding was its potent antiproliferative effect on both tumour cell
lines. This effect was dose-dependent, with half-maximal inhibition
values of IC50 = 4.86 μg/ml and 4.16 μg/ml respectively. This pilot study opens the way for further investigation about the potential use of E. elaterium as an anticancer agent.
Abbreviations
- E. elaterium, Ecballium elaterium (L.) A. Rich.;
- GC–FID, Gas chromatography equipped with flame ionization detector;
- HPLC, high-performance liquid chromatography;
- HT29, human colon adenocarcinoma cell lines;
- HT1080, human colon fibrosarcoma cell lines
Keywords
- Ecballium elaterium;
- Seed oil;
- Chemical composition;
- Antiproliferative activity;
- Colon cancer
1. Introduction
Wild
plant species have always played an important medicinal role in the
history of man. Through academic research, pharmaceutical sciences may
take profit from the available bioresources, and ethnobotanical as well
as ethnopharmacological approaches that would be of interest.
Ecballium elaterium
(L). A. Rich. a wild perennial herb with sub-succulent, hairy leaves
and stems, is widely used in Tunisian folk medicine and possesses
therapeutic activities against a wide range of ailments ( Le Floc’h, 1983 and Boukef, 1986). The mature seeds are the oil-bearing part of the fruit (Alapetite, 1979)
and the watery juice inside the fruit yields a powerful drug called
“elaterium”. It also contains proteins, lipids, cucurbitacins (B, D, E, I
and L,) and cucurbitacin derivatives such as glycosylcucurbitacins and
triterpenoids glycosides ( Lavie and Szinai, 1958, Erclyes et al., 1989, Heitz et al., 1989 and Greige-Gerges et al., 2007). E. elaterium is of interest because its fruits extracts are still used in the Mediterranean region in different medicinal systems ( Rust et al., 2003 and Uslu et al., 2006). Several biological activities of E. elaterium and its components, including anticancer activity, have also been reported ( Lavie and Szinai, 1958 and Chan et al., 2010), but there are no reports on the anticancer activities of the fixed oil of this endemic Mediterranean plant.
Cancer
remains one of the most dreaded diseases causing an astonishingly high
death rate, second only to cardiac arrest. A high number of new drugs
derived from plant secondary metabolites have been applied the treatment
and prevention of cancer (Newman et al., 2003 and Balunas and Kinghorn, 2005).
To our knowledge the cited literature about seeds oil from E. Elaterium only described fatty acid composition ( Erclyes et al., 1989).
In this work we analyse the physical and chemical properties of the
seed oil. Moreover, cell proliferation was fundamental in several
biological processes, especially in cancer (Li and Galileo, 2010), we evaluated the effect of E. elaterium seed oil on the proliferation of human colon adenocarcinoma (HT29) and fibrosarcoma (HT1080) cell lines.
2. Materials and methods
2.1. Materials
Dulbecco’s
modified Eagle’s medium (DMEM) was purchased from GIBCO
(Cergy-Pontoise, France) and foetal calf serum (FCS) from BioWhittaker
(Fontenay-sous-Bois, France). Penicillin, streptomycin, silylant reagent
N-methyl-N-(trimethylsilyl) trifluoroacetamide,
sterols standards, fatty acid methyl esters standards, β-carotene,
silica gel F254 plate and aluminium oxide were purchased from Sigma
Chemical Co. (St. Louis, MO, USA). Potassium hydroxide, n-hexane, diethyl ether, ethanol, acetonitrile, acetone, chloroform were purchased from Fluka Chemical Co. (Buchs, Switzerland).
2.2. Extraction of the seed oil
Fruits of E. Elaterium
were collected in January 2011 from a region of SidiThabet, area of
Ariana (Northern Tunisia, latitude 36°54′45.25″N, longitude
10°06′02.10″E, altitude 30 m). The identification was made by Professor
S. BEN SAAD (Department of Botany, Faculty of Sciences of Tunis) and
voucher specimens (BPn 02-January 2011) were deposited at the
above-mentioned laboratory of Natural Substances to serve as a future
reference.
Seeds were
removed from the mature fruits, washed with water, dried, and then
ground by a grinder to pass 500 μm screens. The ground dried E. elaterium seeds (50 g) were extracted with 250 mL n-hexane
using 24 cycles Soxhlet extraction at 80 °C. The solvent was removed
via a rotary vacuum distillation at 40 °C. The residue was weighed and
stored at −20 °C until analysis. The result was expressed as lipid
percentage in the seed powder dry matter.
