Chemical Composition And Biological Activities Of Essential Oils Of Echinops Spinosus And Carlina Vulgaris Rich In Polyacetylene Compounds

Background: The essential oils of aromatic plants are increasingly used as new biocontrol alternative agents against microbial strains and insect pests of fruits and vegetables, because of their specificity of biodegradable nature.Objectives: This work, treats for the first time the chemical composition, antioxidant, antifungal and insecticidal activities of the essential oils obtained from Echinops spinosus and Carlin vulgaris from Algeria.Methods: The chemical compositions of oils were investigated using GC-FID and GC/MS. Antioxidant activity was assessed using three methods (2,2-diphenyl-1-picrylhydrazyl, Ferric-Reducing Antioxidant Power (FRAP) and beta-carotene assay). Fumigation toxicity of E. spinosus and C. vulgaris essential oils was tested against Bactrocera oleae pests of olives.Results: Eighteen and thirteen components representing 95.4 and 97.9% were identified in root essential oils from Echinops spinosus and Carlina vulgaris, respectively. Polyacetylenes were the majority compounds of essential oils. 5-(But-1-yn-3-enyl)-2,2'-bithiophene and alpha-terthienyle were highly dominants in the E. spinosus essential oil from the roots (54.4 and 26.3%, respectively). Roots of C. vulgaris produce an essential oil dominated by carlina oxide (33.7%) and 13-methoxy carlina oxide (11.5%). Comparison of the antioxidant activity of E. spinosus essential oil showed more important antioxidant effect than C. vulgaris essential oil and the synthetic antioxidant (BHT). Evaluation of the antifungal activity showed an interesting efficiency of both essential oils against P. expansurn and A. niger with EC(50)s varied from 5 to 14.5 mg/L. C. arvensis essential oil exhibited good larvicidal properties. At the concentration of 325 mu L/L air, the oil caused mortality of 100% for Bactrocera Oleae adults after 24 h of exposure.Conclusion: Both essential oils rich to polyacetylenes and polythiophenes.components have shown interesting biological activities, which suggests that plants have the potential to be used as biopesticides and provide an alternative to chemical pesticides.