Abstract: In this study,the composition of anthocyanins in salt-tolerant Ipomoes batatas L.(purple sweet potato) Z103 were analyzed by high performance liquid chromatography (HPLC) coupled with a DAD detector and electrospray ionization tandem mass spectrometry (ESI-MS/MS).In total,15 kinds of anthocyanins were detetced:mainly were cyanidin and peonidin derivatives which were acylated by caffeic acid,ferulic acid,p-hydroxybenzoic acid and other aromatic acid.3 kinds of anthocyanins:cyaniding-3-O-hydroxybenzoyl-sophoroside-5-O-glucoside, peonidin-3-O-hydroxybenzoyl-sophoroside-5-O-glucoside, peonidin-3-O-feruloylsophoroside-5-O-glucoside were detected from this plant for the first time.In addition,four assays,including liposome peroxidation assay,DPPH· scavenging assay,pyrogallol autoxidation assay and Fenton reactions,were used to compare the antioxidant activity of salttolerant purple sweet potato Z103.The results showed that anthocyanins from purple sweet potato (APSP) had high antioxidant activity in a dose-dependent manner.The inhibition rate of APSP (0.4 mg/mL) in liposome peroxidation system was 83.24% and DPPH· scavenge rate of APSP (0.2 mg/mL) was 94.06%,the O₂^-· scavenging rate of APSP (4 mg/mL) was 96.62%,and the HO· scavenging rate reached 96.12% when the dosage of APSP was 30 μg/mL.

Key words: purple sweet potato, anthocyanins, composition analysis, antioxidant activity