Eucalyptus sideroxylon A. Cunn.: A Natural Eucalyptol (1,8-cineole) source in Morocco

Abstract

The main objective of this work is to determine the effect of the harvest period on the yield and chemical quality of the essential oils of the Eucalyptus sideroxylon A. Cunn. leaves of the Mamora forest, Dayet Zerzour Bnifdel region, Rabat. Essential oil yields are remarkably high above 2.3%, with an ultimate rate of 5.48% for the month of April. The chemical quality of these essential oils is characterized by the presence of two major monoterpenes, 1,8-cineole (eucalyptol) and α-terpineol, which are proportionally inverted in terms of quantity. During the wet months between September and March, the cineole predominates with levels ranging from 72.67% to 86.11% and the other dry months are characterized by an increase of α-terpineol rate from 12.05% to 25.61%. This inverted chemical variability reveals a change in the orientation of cineole and α-terpineol biosynthesis under the control of climatic factors. This work allows us to discern favorable periods for the harvest of Eucalyptus sideroxylon leaves in terms of yield and quality of essential oils.