Anti-tumor and immunomodulating activities of a polysaccharide from the root of Sanguisorba officinalis L.

A water-soluble polysaccharide, named as SOWP, was extracted and fractioned from the roots of Sanguisorba officinalis L. by DEAE-Sepharose anion exchange and Sepharose 6 Fast Flow column chromatography. The monosaccharide composition of SOWP determined by gas chromatography (GC) identified it was composed of glucose (68.5%), arabinose (13.2%), rhamnose (8.9), xylose (6.2) and galactose (3.0%). At the dose of 50, 100, and 200 mg/kg, SOWP not only significantly inhibited the growth of mouse transplantable tumor, but also remarkably increased the spleen index and promoted splenocytes proliferation, macrophage phagocytosis and the production of serum cytokines IL-2, TNF-α and IFN-γ in Sarcoma 180-bearing mice. However, no direct cytotoxic activity against Sarcoma 180 cells was observed. The anti-tumor activity of the polysaccharide from S. officinalis maybe achieved by not directly cytotoxicity but rather immunopotentiation.