Chinese yam peel polysaccharide as well as preparation method and application thereof

The invention discloses Chinese yam peel polysaccharide as well as a preparation method and application thereof. The preparation method of the Chinese yam peel polysaccharide comprises the following steps: (1) carrying out acid extraction on Chinese yam peel, and collecting an acid extract; and (2) neutralizing the acid extract, performing alcohol precipitation, collecting the precipitate, and drying to obtain the Chinese yam peel polysaccharide. Compared with a water extraction method and an enzyme extraction method, the method for obtaining the Chinese yam peel polysaccharide by adopting acid extraction has the advantages that the yield of the obtained Chinese yam peel polysaccharide crude sugar is high; the obtained crude polysaccharide is further purified by adopting deproteinization and dialysis methods, and the purity of the obtained Chinese yam peel polysaccharide is high; and tests prove that the Chinese yam peel polysaccharide disclosed by the invention has higher antioxidant activity and hypoglycemi