Chemical Variability of Atractylis gummifera Essential Oils at Three Developmental Stages and Investigation of Their Antioxidant, Antifungal and Insecticidal Activities

Background: Atractylis gummifera is a cosmopolitan species that is particularly abundant in the Mediterranean regions. It has been used to treat many diseases, including intestinal parasites, ulcers, snakebite poisoning, hydrops and drowsiness. As part of our research program on natural compounds with biological activities, the objective of this study was to determine for the first time the chemical composition and biological activities of essential oils of Atractylis gummifera during beginning of the vegetative cycle (March), beginning of the flowering stage (April) and full bloom (May/June). Methods: The essential oils were obtained by means of hydrodistillation and its components were analyzed using gas chromatography and mass spectrometry (GC/MS). The antioxidant properties were evaluated using two different methods i) Radical scavenging activity (DPPH) and ii) β-carotene bleaching assay. Whereas, the antifungal activity of the essential oils was investigated against five plant fungi. The fumigation toxicity of essential oils was evaluated against adults of Bactrocera oleae better known as the olive fly. Results: The essential oil produced from the plant taken at the beginning of the vegetative cycle (March) had a high level of non-terpenic aliphatic compounds. On the other hand, the essential oil obtained during the period from the beginning of the flowering stage (April) showed that its proportion of non-terpene compounds decreased and that of sesquiterpene compounds increased. Finally, the essential oils obtained during the period from full bloom (May/June) consisted mainly of acetylene compounds such as carlina oxide and 13-methoxy carlina oxide. The results showed that essential oils from plants at full bloom presented interesting antioxidant and antifungal properties, while essential oil produced from plants at the beginning of the vegetative cycle (Mars) and at the beginning of the flowering stage (April) had better insecticidal activity. Conclusion: The data presented here constitutes new findings in the field of the chemical characterization and biological potential of A. gummifera.