Harvest date and variability in lipid bioactive compounds in Pistacia atlantica

BACKGROUND: The present work stands as an endeavor to uncover the ideal harvesting time of leaves in which they exhibits the maximum contents of bioactive molecules such as essential fatty acids, tocopherols and carotenoids. METHODS: A large scale investigation was carried out for the leaves of Pistacia atlantica involving a large number of populations collected over a period of four months during the growing season. The antioxidant activity was evaluated using both DPPH and β-carotene assays. The chemical percentage variability of the fatty acids was investigated using statistical analysis methods (Agglomerative Hierarchical Clustering “AHC”, also cited as CAH). OBJECTIVE: During the growth period, the effects of harvesting date on the total contents of lipids, tocopherols, carotenoids, fatty acids composition and also the antioxidant activities of the lipids were investigated. RESULTS: The content of myristic acid and other saturated fatty acids increased during leaf development, while linoleic, linolenic acids and unsaturated fatty acids decreased. The highest percentages of both linolenic C18:3 (27.25±5.92%) and linoleic acids C18:2 (17.68±3.80%) were obtained for the month of May at the first stage of leaves development (young leaves), but higher percentage levels of C18:1, were obtained for both consecutive months of August & September (28.83±6.50%; 27.79±8.63%, respectively) at intermediate developing stage. The lipids, tocopherols, carotenoids contents and the saturated and unsaturated fatty acids were dependent on the harvest time. The antioxidant activity showed higher powers at the first developing stage (May). Two main clusters and two sub-clusters of the fatty acids were distinguished and were also depending clearly on the period of the collection. CONCLUSIONS: The results showed that the FA were dependent on the period of collection of the leaves. The main result of this study illustrate the nutritional potential (richness in MUFA such as C18:1, 2, 3) of the oil of P. atlantica leaves, which can provide opportunities for rational exploitation in the food industries or for medicinal purposes.