GC-MS analysis of essential oil obtained from the seed of Foeniculum vulgare showed the presence of 31 components containing 95.2% of the total amount and the major component was trans-anethole (70.1%). The analysis of ethanolic and methanolic seed extracts showed the presence of nine components including linoleic acid (56%), palmitic acid (5.6%) and oleic acid (5.2%). The antimicrobial activity of F. vulgare oil was assessed by using disk diffusion as well as minimum inhibitory concentration (MIC) method. Fennel oil showed inhibition against Bacillus cereus, Bacillus magaterium, Bacillus pumilus, Bacillus substilis, Eschericha coli, Klebsiella pneumonia, Micrococcus lutus, Pseudomonos pupida, Pseudomonos syringae, and Candida albicans as compared to methanolic and ethanolic seed extracts. The lowest MIC values of fennel oil for Candida albicans (0.4% v/v), Pseudomonos putida (0.6% v/v) and E. coli (0.8% v/v) was obtained. It was observed that essential oil and seed extracts of F. vulgare exhibit different degree of antimicrobial activities depending on the doses applied. Therefore, fennel oil could be a source of pharmaceutical materials required for the preparation of new therapeutic and antimicrobial agents

Key words: Foeniculum vulgare, essential oil, antibacterial agent, GC-MS analysis, analytical techniques.