Comparison of phytochemical constituents and antioxidant activities of aqueous and alcoholic extracts of saffron

Abstract

In the present work, phytochemical compounds and antioxidant activities of three aqueous, ethanolic (50 and 80%, v/v) and methanolic (50 and 80%, v/v) extracts of saffron during 1 and 24 h of shaking time were compared. Results showed that the ethanolic solution (80%, v/v) extracted for 24 h had the highest amounts of phenolic compounds (29.2 g gallic acid (Gal)/g dry weight (DW)), followed by 1 h aqueous extract (17.53 mg Gal/g DW) and 1 h methanol extract (50%, v/v, 14.5 mg Gal/g DW). The total flavonoid contents for all extracts were varied from 0.20 to 0.56 mg quercetin/g DW. Although all the extracts were capable to scavenge the 2,2'-diphenyl-1-picrylhydrazyl free-radical, ethanolic extract was found to be the best antioxidant activity (84.22%). Solvent type and extraction time had significant effects on the antioxidant capacities and phytochemical contents of the saffron extracts. A significant positive correlation was found between the antioxidant activity, total phenolic (r2=0.991) and flavonoid (r2=0.996) contents (P<0.05) for 24 h the extracted extracts. High performance liquid chromatography analysis also demonstrated that the components amounts of crocins, picrocrocin and safranal were varied in the saffron samples extracted from the different solvents.