Antioxidant and antimicrobial activities of essential oil and extracts of fennel (Foeniculum vulgare Mill.) seeds from Pakistan

The present study was conducted to examine the antioxidant and antimicrobial activities of essential oil, methanol and ethanol extracts of fennel (Foeniculum vulgare Mill.) seeds native to Pakistan. The seed essential oil and extract yields from fennel seeds were found to be 2.81 and 6.21-15.63% w/w, respectively. GC and GC-MS analysis of the fennel essential oil revealed the presence of 23 compounds, with trans-anethol (69.87%), fenchone (10.23%), estragole (5.45%) and limonene (5.10%) as the major components. The fennel seed extracts contained appreciable levels of total phenolic contents (627.21-967.50 GAE, mg/100 g) and total flavonoid contents (374.88-681.96 CE, mg/100 g). Fennel essential oil and extracts also exhibited good DPPH radical scavenging activity, showing IC50 32.32 and 23.61-26.75 mu g/ml, and inhibition of peroxidation 45.05 and 48.80-70.35%, respectively. Of the fennel essential oil and solvent extracts tested, 80% ethanol extract exhibited the maximum antioxidant activity, whereas the essential oil showed appreciable antimicrobial activity against selected strains of bacteria and pathogenic fungi. The results of the present investigation demonstrated significant (p < 0.05) variations in the antioxidant and antimicrobial activities of fennel essential oil and extracts. Copyright (C) 2009 John Wiley & Sons, Ltd.