Aqueous Extract of Wild Cyclamen Tubers (Cyclamen Purpurascens L.) - A Potential Source of Natural Antioxidants and Antimicrobial Agents

Wild cyclamen tubers (Cyclamen purpurascens Mill.) (mountain Kukavica, Southeast Serbia) were used as material for extraction in this study. Aqueous extract was obtained by reflux extraction on boiling temperature with hydromodulus 1:20 m/v during 180 minutes. The total phenolic content was determined spectrophotometrically by the method of Folin-Ciocalteu, and the total flavonoids content by method with AlCl3. The antioxidant activity of extract was investigated spectrophotometrically by DPPH and ABTS test. Disc-diffusion method was used for antimicrobial activity investigation on the following pathogenic microorganisms: Staphylococcus aureus, Bacillus cereus, Enterococcus faecalis, Pseudomonas aeruginosa and Klebsiella pneumoniae. The content of total phenols was 8.27 mg GAE/g dry extract while the total flavonoid content was 11.51 mg RE/g dry extract. The extract concentrations required to neutralize 50% of the initial concentration of DPPH radicals (EC50) after 20 minutes incubation and immediately after adding DPPH radical solution were 0.413 and 2.0 mg/ml, respectively, while concentrations of extract required to neutralize 50% of the initial ABTS radicals concentration is 0.743 mg/ml. The extract showed the highest antimicrobial activity on bacteria Staphylococcus aureus. The presented results indicate that cyclamen tubers extract is a potential source of natural antioxidants and antimicrobial agents.