Carrot seed essential oil—Source of carotol and cytotoxicity study

Abstract

Carrot seed essential oil is a common fragrance component in cosmetics and perfumes and a flavor ingredient in different categories of food products. It is also a major source of sesquiterpene alcohol carotol. In this work we aimed to compare carotol content in commercially available (Moroccan and French) and hydrodistilled (Polish) wild carrot seed essential oils (Daucus carota L. ssp. carota) and to evaluate cytotoxicity of these essential oils, as well as isolated carotol. The chemical composition of studied essential oils was analysed by gas chromatography- mass spectrometry. Cytotoxicity tests were performed on green monkey kidney (VERO) and human pharynx squamous cell carcinoma (FaDu) cell lines. Carotol and other terpenoids were isolated using high performance counter current chromatography technique in the reversed phase mode, with a mixtures of n-hexane/acetonitrile/tetr-butyl methyl ether (1:1:0.1 and 2:1:0.1v/v). Carotol was the main constituent in three carrot seed essential oils of different origin amounting 19–33% of the sum of compounds. α-Pinene, sabinene, myrcene, limonene, geranyl acetate, bisabolene, cayophyllene oxide and daucol were identified as other main compounds. Separation of 280mg of carrot seed essential oil yielded carotol (20mg) and other terpenoids: α-pinene, sabinene, limonene, geranyl acetate, caryophyllene oxide, and daucol with the purity in the range of 80–99%. The applied method enabled isolation of all main constituents of essential oil in the single run. The comparison of cytotoxicity of tested essential oils on VERO and FaDu cell lines indicated that Moroccan and French essential oils have similar cytotoxicity (35.3–46.1μg/mL), while Polish essential oil showed lower cytotoxic effect (70.9–96.3μg/mL). Carotol being the main constituent of all tested essential oils showed moderate cytotoxicity on both tested cell lines without any selectivity.