Radix asparagi homogeneous polysaccharide, preparation method thereof and application of radix asparagi homogeneous polysaccharide in preparation of medicine for treating nervous system diseases

The invention discloses radix asparagi homogeneous polysaccharide, a preparation method thereof and application of the radix asparagi homogeneous polysaccharide in preparation of a medicine for treating nervous system diseases. The radix asparagi homogeneous polysaccharide is prepared from fucose, rhamnose, arabinose, galactose, glucose, xylose and fructose. Crushing radix asparagi, adding a hydrochloric acid solution, decocting, cooling the decoction, and filtering to obtain a radix asparagi polysaccharide extracting solution; adjusting the pH value of the radix asparagi polysaccharide extracting solution by adopting a NaOH solution, then evaporating and concentrating to obtain a fluid extract, and carrying out alcohol precipitation on the fluid extract to obtain alcohol precipitation crude polysaccharide; deproteinizing the alcohol-precipitated crude polysaccharide by using a Sevag method to obtain total polysaccharide of radix asparagi; separating and purifying the radix asparagi total polysaccharide, and