Study on Extraction of Polyphenol from Grape Peel and Its Antioxidant Activity

In this paper,the extraction process of polyphenol from grape peel was studied by single factor experiment and orthogonal experiment.The optimum extraction conditions were determined as follows:the extraction temperature 80℃,the volume fraction of ethanol 50%,the extraction time 30 min,the ratio of material to liquid 1∶9.Extracted under above conditions for two times,the extraction amount of polyphenol from grape peel reached 13.065 mg·g-1.The antioxidant activity of polyphenol abtained was explored.It was found that the cleavage rate of hydroxyl radicals was about 55% when the dosage of polyphenol extraction solution was 2.5 mL.