Characterization of polysaccharides extracted from Platycodon grandiflorus (Jacq.) A.DC. affecting activation of chicken peritoneal macrophages.

Polysaccharides were isolated from Platycodon grandiflorus (Jacq.) A.DC. (PG) and the effects of three polysaccharides (PGPS, PGPS, PGPS) on their immunological activities were studied. The structure identification of PGPSs was assessed using physicochemical and spectral methods. Results showed that PGPS(2.67×10Da) compared to PGPS(1.01×10Da) and PGPS(1.12×10Da) has relatively higher average molecular weight(Mw) at the first peak with a narrower molecular weight distribution and all consisted of glucose, mannose, arabinose, galactose, xylose and rhamnose in different mass percentages. PGPS and PGPS linked mainly by 1,3-and 1,6-β-d-Galp residues. The immunological efficacy of PGPSs was performed on chicken peritoneal macrophages. Results showed that PGPS significantly increased phagocytic rates, proliferation and NO production, stimulated macrophages to produce cytokines, including TNF-α, IL-1β and IL-6 as well as stimulated macrophages to express the maturation markers CD80 and CD86. These findings suggest that PGPS exerted significant immunological activity and might be associated with special characters.