关键词: 化学组分, 抗氧化性, 紫甘薯, 花色苷

Abstract: Anthocyanins extracted from purple sweet potatoes (Ipomoea batatas L.) were purified through AB-8 resin column. The extract contains 11 kinds of anthocyanins by HPLC-DAD analysis. The majority of the anthocyanins are acylated cyanidin and peonidin. The objective of this study was to investigate the antioxidant activities of anthocyanins from purple sweet potatoes by different analytical methods: the α,α-diphenyl-β-picrylhydrazyl (DPPH) radical-scavenging effect and superoxide anions radical-scavenging effect, reducing power and antioxidant effect on lipid peroxidation in a linoleic acid model system. At a concentration of 0.5g/L, the reducing power of anthocyanins, L-ascorbic acid (L-AA) and butylated hydroxytoluene (BHT) reached 0.572, 0.460 and 0.121, respectively. The result displayed that anthocyanins possessed excellent reducing power. The fact that half inhibition concentrations (IC₅₀) of anthocyanins scavenging DPPH radical and superoxide anions radical were 6.94 and 3.68mg/Lrespectively indicates that anthocyanins were effective in scavenging DPPH and superoxide anions radical. In addition, anthocyanins could significantly inhibit the peroxidation of lipid.

Key words: chemical constituent, antioxidant activity, Ipomoea batatas L.(purple sweet potato), anthocyanins