Investigation of n-Butanol and Ethyl Acetate Extracts from Thermal Treatment Yam (Dioscorea batatas DECNE.) for their Antioxidant Activities

n-Butanol and ethyl acetate extracts of thermal treatment yam (Dioscorea batatas DECNE.) belonging to the family Dioscoreaceae were measured for their radical scavenging activity and lipid peroxidation inhibition ability. In this study, ethyl acetate extract showed the most potent antioxidant activity evaluated by ferrous ion chelating activity and NO radical scavenging activity. Nevertheless, n-butanol extract was more effective in inhibiting linoleic acid peroxidation. A significant difference between n-butanol extract and ethyl acetate extract in nitrite scavenging activity β-carotene bleaching assays could not be found. Also, the results of this study showed that thermal treatment yam could be used as easily accessible source of natural antioxidants and as a possible food supplement.