Variation in essential oil composition and biological activities of Foeniculum vulgare Mill. populations growing widely in Tunisia

Chemical composition, antioxidant, and antimicrobial activities of essential oils from 16 wild edible Tunisian Foeniculum vulgare populations were evaluated. The essential oil yields of fennel seeds ranged from 1.2 to 5.06%. GC-MS analysis revealed the presence of 20 compounds. Except one sample, essential oils from different locations were mainly composed of phenylpropanoid and the major compound was estragole with a percentage ranging from 66.09 to 85%. The phenolic content of fennel oils varied significantly among populations which could explain the high variation in antiradical scavenging activity. Furthermore, essential oils presented antimicrobial activity against several strains. Results showed that the Gram-positive strains of bacteria were most sensitive to fennel oils. This study encourages the use of wild fennel as a potential source of natural antioxidants and antimicrobial agents and supports an assessment of this species in several application domains. Practical applications: The growing interest in the use of medicinal plants in food and pharmaceutical industries has led to a systematic examination of plant extracts for their biological properties. Wild fennel is one of aromatic and medicinal plant known for its biological and pharmaceutical activities. In this study, chemical composition, antioxidant, and antimicrobial activities of fennel essential oil were analyzed with a view of their industrial applications. The variations in essential oil composition and their biological activities in different populations may provide baseline data for breeding programs and large scale multiplication for commercial cultivation of the best fennel population.