Volatiles Variation of Two Major Cultivars of Olea europaea L. Cultivated in Mediterranean and Arid Regions of Algeria

The chemical compositions of the volatile fractions, produced by the flowers and leaves of two Olea europaea L. cultivars (Chemlal and Sigoise) were investigated. The plant materials were harvested from two different zones in Algeria (Mediterranean and arid regions). The samples were extracted by hydrodistillation using a Clevenger apparatus. GC-MS analysis allowed the identification of 51 compounds. According to the geographic origin and the cultivar, qualitative and semi-quantitative variations were observed, especially with the abundance of the main compounds. Overall, the principal component analysis showed that the environmental condition was mainly affecting the production of the major compounds. Throughout the two regions, the main substances in the samples from the Mediterranean region were (Z)-jasmone (51.8%), nonanal (32.4%), theaspirane II (23.7%) and phenylethyl propionate (17.9%). While those of the arid region were bornyl acetate (26.8%), 3-ethenyl pyridine (17.2%), (E,E)-2,4-heptadienal (16.9%) and (E)-geranylacetone (14.4%), with a significant correlation between the flower volatiles, more than 86% in both regions. These results can add a valuable insight into the effect of arid climate on the production of volatiles by Olea europaea.