Abstract: This study aimed to optimize the ultrasonic-assisted extraction of anthocyanins from Aronia melanocarpa and to determine the antioxidant capacity and constituents of the obtained extract. The optimization was carried out by response surface methodology. The 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, 2,2’-azinobis-(3-ethylbenzthiazoline-6-sulphonate) radical (ABTS+·) scavenging capacity and Fe3+ reducing ability of plasma (FRAP) assays were used to evaluate the antioxidant capacity. The anthocyanin components were analyzed by high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS). The results showed that the optimum extraction conditions were as follows: extraction temperature 60 ℃, ultrasonic power 100 W, solid-to-liquid 1:30 (g/mL), ultrasonic time 31 min, ethanol concentration 64%, and pH 2.0. Under these conditions, the content of anthocyanins was determined to be (3.61 ± 0.01) mg/g. The in vitro antioxidant activity of the anthocyanin extract was significantly higher than that of vitamin C at the same concentration. Six anthocyanins including two new compounds, dimer of cyanidin-3-hexoside and cyanidin-3,5-dihexoside, were detected in the extract.

Key words: Aronia melanocarpa, anthocyanins, response surface methodology, antioxidant activity, high performance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS)