Preparation method of gelidium amanisi polysaccharide

The invention discloses a preparation method of gelidium amanisi polysaccharide. The preparation method comprises the following steps: (1) pre-treating a dry gelidium amanisi product and superfinely grinding and screening the dry gelidium amanisi product to obtain a gelidium amanisi powder; (2) adding water into the gelidium amanisi powder, adding a compound enzyme of papain and cellulose after preheating, and carrying out enzyme deactivation treatment after enzymolysis; (3) carrying out centrifugalization after enzyme deactivation, abandoning residues, and rotatably concentrating a supernate;(4) adding absolute ethyl alcohol into the rotary concentrated product for alcohol precipitation; and (5) carrying out centrifugalization after alcohol precipitation, abandoning the supernate, and washing the precipitate and freezing and drying the precipitate to obtain the gelidium amanisi polysaccharide. The method is short in production period, high in efficiency and hard to degrade polysaccharide, and the obtained ge