Evaluation of Antifungal and Antioxidant Properties of Fennel Extract

  The recent literature search has introduced fennel and its extracts as potential products with excellent properties and characteristics. The aim of this investigation is to obtain fennel extracts and evaluate its antioxidant and antifungal activities. Water, acetone, methanol and ethanol were employed as solvents and extracts were obtained by soxhlet procedure. The amount of polyphenolic and flavonoid compounds of each extract was determined. In addition, the antioxidant activity of methanolic extract of fennel was evaluated based on DPPH radical scavenging activity. Afterwards, the effect of different concentrations of methanolic extract (0, 100, 250, 500 and 1000 ppm) and powder (500 and 1000 ppm) of fennel on the oxidantion activity of sunflower seed oil was investigated in terms of peroxide and thiobarbituric acid values during 15 days of incubation at 70 ⁰C. The antifungal activity of powder and extract of fennel against Aspergillus niger and Penicillium digitatum was also investigated by disc diffusion test. According to the obtained results methanol represented the highest efficiency in extraction of phenolic compounds. The results indicated that fennel extract, especially at high concentrations, showed high DPPH radical-scavenging activity, however its effect was lower than that of TBHQ. The results of oxidation activity showed that the extract and powder of fennel, decreased the oxidation rate of sunflower seed oil as compared to the control. The results of microbiology test indicated good antifungal activity of fennel extract against the two tested microorganisms. Considering the results, fennel extract can be applied as a healthy plant source with good antioxidant and antifungal activities.