Extraction and antioxidant activity of polyphenols from pomegranate slag

To optimize the extraction of polyphenols from pomegranate seed and research its antioxidant activity.Methods: By traditional solvent extration method obtained the polyphenols in pomegranate seed, then determined by Folin-Ciocalteu ( FC) method.The levels of the four variables were optimized using response surface methodology ( RSM) with central composite design.The antioxidant activity was determined by 2, 2-Diphenyl-1-picrylhydrazyl ( DPPH) free radical scavenging ability and the assays of deoxidization capability.Results: The optimal conditions were determined as follows: extraction time of 3.5 h, extraction temperature of 62 ℃, ethanol concentration of 41%, and liquid-solid of 20 m L/g.Under these condition, the extraction value of polyphenols was 4.88 mg GAE/g material, which is accordance with the predicted value 5.034 mg GAE/g material.There is a positive correlation between polyphenols concentration from pomegranate seeds and DPPH free radical scavenging, and the correlation coefficient is 0.9988.