Characterization and immunoregulatory activity of two polysaccharides from the root of Ilex asprella

The polysaccharides obtained from the root of Ilex asprella, namely IAPS-1 and IAPS-2, with immunoregulatory activity were studied. Two polysaccharides were isolated and purified by Cellulose DEAE-52 and Sephadex columns. The structure of IAPS-1 was elucidated as 1,6-linked alpha-D-glucopyranosyl main chain with branch chain substituted at C-2 and/or C-4 position. For IAPS-2, the backbone is composed of 1, 4-linked alpha-D-glucose, galactose and rhamnose, and branched chains consists of arabinose, rhamnose and galacturonic acid, as confirmed by partial acid hydrolysis and NMR study. Further, the immunoregulatory activity of IAPS-1 and IAPS-2 was tested with the murine macrophages. Particularly, IAPS-2 polysaccharide can more effectively enhance the secretion of major inflammatory cytokines in macrophages, such as TNF-alpha, IL-1 beta, IL-12, compared with IAPS-1.