Preparation method of vine of multiflower knotweed polysaccharide

The invention relates to a preparation method of vine of multiflower knotweed polysaccharide, effectively solving the preparation problem of the multiflower knotweed polysaccharide. The method comprises the following steps: firstly drying and smashing the vine of multiflower knotweed to prepare the powder of the vine of multiflower knotweed; mixing the powder of vine of multiflower knotweed with an aqueous alkali, extracting by the water bath and reflux, filtering, mixing the filtrate, regulating the pH, concentrating, adding with the ethanol, standing, and removing the supernate by centrifugation to obtain a first polysaccharide sediment; then dissolving the first polysaccharide sediment in distilled water to prepare a polysaccharide solution, running a resin column until the effluent liquid has the absorbance at 473nm same as the absorbance of the supernatant in the resin column, i.e. achieving the saturation adsorption of the macroporous absorption resin, eluting the resin column by distilled water and sto