Effects of extraction solvent/technique on the antioxidant and antimicrobial activity of spring saffron (Crocus vernus (L.) Hill)

Abstract

Spring saffron (lat. Crocus vernus (L.)Hill) is a perennial from the Iridaceae family. Purple or white coloured flowers bloom in the early spring. Saffron is commonly used in cookery, but because of its healing properties, crocus is also used in medicine for improving blood circulation, treating the cardiovascular diseases, preventing tumour and healing skin diseases. This research aimed to determine the influence of solvents (water, ethanol and acetone) on antioxidative, antimicrobial activity and the content of biologically important compounds, such as phenols and flavonoids in saffron. FRAP and DPPH methods were used to examine antioxidative activity. Antibacterial activity was analysed by using diffusion technique on bacterial strains of Escherichia coli, Enterococcus faecalis, Staphylococcus aureus, Bacillus subtilis, Listeria monocytogenes, and Pseudomonas aeruginosa. Antifungal activity was examined on Candida albicans. The results showed that the ethanol extracts have the highest antioxidant activity and the aqueous extracts have the lowest one. None of the tested extracts showed antibacterial activity, but aqueous extracts and ethanolic extract of saffron, obtained by maceration, showed antifungal activity.