Separation, purification and immunomodulatory activity of polysaccharides from Rubus sachalinensis / 中草药

ABSTRACT

Objective: To extract, separate and purify homogeneous polysaccharides from Rubus sachalinensis and study on monosaccharide component and immunomodulatory activity. Methods: The crude polysaccharides of Rubus sachalinensis (RSP) were extracted by hot water. The Cellulose DE-52 and Sephadex G-100 columns were used to separate and purify homogeneous polysaccharides. The relative molecular mass was analyzed by high-performance gel permeation chromatography, and the monosaccharide composition and structure were preliminarily identified by GC, IR and NMR. The effects on proliferation function of mice spleen lymphocyte proliferation were determined by CCK-8, and the effects on the release capacity of IL-2, IFN-γ and TNF-α were determined by the ELISA kit. Results: Two homogeneous polysaccharides, RSP1-1 and RSP1-2, were separated and purified, with molecular weights of 13 227 and 9 343 determined by HPGPC. They mainly contained arabinose, mannose, glucose and galactose, with the mole ratios at 9.57.010.318.6 and 5.711.110.314.2, respectively. The structure of RSP1-1and RSP1-2 was analyzed by IR and NMR, and RSP1-1 might mainly contain α-1,3-Ara, β-1,4Gal, β-1,6-Glc, β-1,3-Man, and RSP1-2 might mainly contain β-1,4-Gal, β-1,6-Glc, β-1,3-Man. At 5-200 μg/mL, RSP1-1and RSP1-2 stimulated proliferation of spleen lymphocytes (P < 0.05) and promoted lymphocytes to secrete IFN-γ and TNF-α. At 5 μg/mL, RSP1-1and RSP1-2 promoted lymphocytes to secrete IL-2. Conclusion: RSP1-1and RSP1-2 are natural homogeneous polysaccharides that are obtained from this plants for the first time. Its purity and structure were further characterized by IR and NMR. These two homogeneous polysaccharides promoted the proliferation of splenic lymphocyte in different degrees and promoted lymphocytes to secrete IL-2, IFN-γ and TNF-α that all possessing immunomodulating activity.