Oyster polysaccharide extract and preparation method thereof

The invention relates to an oyster polysaccharide extract and a preparation method thereof. The preparation method of the oyster polysaccharide extract comprises the following steps: mixing primarily processed oyster meat with water, and pulping to prepare oyster pulp; amylase and compound protease are added into the oyster pulp for enzymolysis, enzyme deactivation is conducted, and enzymatic hydrolysate is prepared; inoculating lactic acid bacteria into the enzymatic hydrolysate for first fermentation to prepare a first fermentation product, and collecting fermentation liquor from the first fermentation product to prepare first supernate; inoculating saccharomyces cerevisiae embryos into the first supernate for secondary fermentation to prepare a second fermentation product, and collecting fermentation liquor from the second fermentation product to prepare the oyster polysaccharide extract. In the enzymolysis process, protein in the oysters is decomposed into amino acid to the maximum extent, then the amino