Effect of Extraction Conditions on Antioxidant Properties of Anthocyanins from the Fruits of Lonicera edulis

Anthocyanins in the fruits of Lonicera edulis was extracted using aqueous ethanol, and the effects of six extraction conditions on anthocyanin extraction and the abilities of the extracted anthocyanins to scavenge hydroxyl and DPPH free radicals were evaluated by single factor and orthogonal array design methods. Using the Z-score comprehensive evaluation method, the orthogonal array experimental results were analyzed. UV spectrophotometry and a H2O2/Fe system were used to determine anthocyanin extraction yield and hydroxyl free radical scavenging rate, respectively. Ethanol concentration of 70%, material/liquid ratio of 1:15, extraction temperature of 60 ℃, extraction duration of 90 min, pH of 2 and extraction number of 3 were found optimal. The absorbance at 520 nm of the extract obtained under the optimal extraction conditions was 0.789, and tis hydroxyl free radical and DPPH radical scavenging rates were 18.92%and 41.57% respectively.