Radical scavenging activity of fried chips made from purple-fleshed sweet potato

Superoxide radical (O-2(-)) scavenging activity Of fried chips made from purple-fleshed sweet potato was investigated. The twelve chips used in this study were commercially available in Kyushu and Okinawa region. All chips showed O-2(=) scavenging activity in the range of 152 to 883 units/g expressed as a superoxide dismutase equivalent. Radical scavenging activity of the fried chips was measured by another method using 1,I-diphenyl-2-picrylhydrazyl (DPPH). DPPH radical scavenging activity of the fried chips highly correlated with O-2(-) scavenging activity (r=0.901), indicating the calorimetric assay using DPPH was effective as an alternative to estimate O-2(-) scavenging activity. In addition, the HPLC analysis of anthocyanins in the chips reveled that the HPLC elution pattern was subdivided into two groups. As judged by the HPLC pattern, it could be presumed that which cultivar was used in the chips.