Comparative essential oil composition and antifungal effect of bitter fennel (Foeniculum vulgare ssp. piperitum)...

The chemical composition of the flower and unripe and ripe fruits from fennel (bitter) (Foeniculum vulgare ssp. piperitum) has been examined by gas chromatography and gas chromatography-mass spectrometry. The main identified components of the flower and unripe and ripe fruit oils were estragole (53.08%, 56.11%, and 61.08%), fenchone (13.53%, 19.18%, and 23.46%), and alpha-phellandrene (5.77%, 3.30%, and 0.72%), respectively. Minor qualitative and major quantitative variations for some compounds of essential oils were determined with respect to the different parts of F. vulgare. The oils exerted varying levels of antifungal effects on the experimental mycelial growth of Alternaria alternata, Fusarium oxysporum, and Rhizoctonia solani. The 40 ppm concentrations of fennel oils showed inhibitory effect against mycelial growth of A. alternaria, whereas 10 ppm levels were ineffective. The analyses show that fennel oils exhibited different degrees of fungistatic activity depending on the doses.