Chemical characterization of Lavandula latifolia Medik. essential oil from Spanish wild populations

Abstract

A survey of Lavandula latifolia Medik. wild populations was carried out covering the distribution area of the species in Spain. Samples (194) from 6 different biogeographic provinces were gathered, dried, hydrodistilled and their essential oils analyzed by gas chromatography (GC). Forty compounds were identified, three of them (1,8-cineole, linalool and camphor) accounting for more than 70% of the total oil in all the analyzed samples. Linalool and camphor were inversely correlated. Camphor production seemed to be helped by lower altitudes. Two-step clustering analysis was conducted and samples were classified into three different clusters: C1 characterized by its high content in camphor, borneol, camphene, α- and β-pinene; C2 characterized by its high content in linalool and terpinen-4-ol and C3 characterized by the presence of limonene, transcaryophyllene and/or β-phellandrene, compounds that did not appear in significant percentages in the other two groups. C1 populations are the most frequent in samples from Eastern and North-Eastern Iberian Peninsula (Balearic-Catalonian-Provençal and Cévenno-Pyrenean biogeographic provinces). Populations from Central Iberian Peninsula (Mediterranean Central and West Iberian biogeographic provinces) and upland areas from the South of Spain (Betican and Murcian-Almerian biogeographic provinces) were mainly grouped in C2. C3 samples were also found in Cévenno-Pyrenean province and, to a lesser extent, in the Central provinces (Mediterranean Central and West Iberian). This distribution showed certain relationship between the chemical composition of the essential oils and their geographical origin.