Comparative GC-MS Analysis of Bay Leaf (Laurus nobilis L.) Essential Oils in Commercial Samples

Chemical composition of Laurus nobilis essential oils traded as spice and medicinal items was analyzed by gas chromatography-mass spectrometry. Sixty-four compounds accounting between 91-99% of the total oil was identified. Qualitative and quantitative differences were found among essential oils obtained from bay leaves used both for cooking and medicinal purposes. The oxygenated compounds were the principal fraction in all analyzed oils and consisted in oxygenated monoterpenes (73.13%), in medicinal essential oil and oxygenated monoterpenes (37.60 and 29.82%), oxygenated sesquiterpenes (15.98 and 22.99%), and phenylpropanoids (24.78 and 26.33%), respectively, in commercial food items. A high content of methyl eugenol (19 +/- 4%; 21 +/- 1%) and a-terpinyl acetate (18 +/- 5%; 17 +/- 7%) was found in commercial food items, whereas 1,8-cineole (51%) and alpha-terpinyl acetate (10%) were the main compounds in commercial pharmaceutical items.