Determination of Antioxidant Properties of Six By-Products of Crocus sativus L. (Saffron) Plant Products

Purpose Crocus sativus L. is one of the spices believed to possess antioxidant activities. The stigma of saffron has been widely used as spice for culinary purposes, food colorant and medicinal plant. In this research, we evaluate and compare the antioxidant properties of ethanolic extracts of six different by-products of Crocus sativus plant including dry leaves, green leaves, corms, tunics, spaths and stigmas. Methods The antioxidant activity was evaluated using in vitro assays such as total antioxidant capacity, DPPH free radical, Scavenging of H2O2 , FRAP and beta-carotene bleaching assay. Results The results showed that all extracts possess antioxidant properties and scavenging activities. Extract from stigmas revealed lower activity than that of other by-products, corms extract showed the highest level of free radical-scavenging activity. Spaths extract showed the strangest protection from beta-carotene bleaching between all extracts. Conclusions Therefore, all by-products produced from the harvesting of saffron stigma could be applied as a natural antioxidant source for biological activities.