Antitumor and immunomodulating activity of a polysaccharide from Sophora flavescens Ait.

► We purified a polysaccharide from the roots of Sophora flavescens. ► S. flavescens polysaccharide inhibit H22 tumor growth in mice. ► Simultaneously this polysaccharide has potent immunostimulating activity. ► The antitumor effect of this polysaccharide is related to immunostimulation.