Effect of sulfation and partial hydrolysis of polysaccharides from Polygonatum sibiricum on immune-enhancement

The aqueous polysaccharide from Polygonatum sibiricum was extracted and fractionated using anion-exchange chromatography to obtain F-1 fraction. The F-1 was chemically sulfated and partially acid-hydrolyzed for the production of its over-sulfated (OS1,2,3) and hydrolyzed (HP1,2,3) derivatives, in which the sulfate content of OS1,2,3 was 7.5-17.1%, and the M-w of HP1,2,3 ranged from 18.2 x 10(3) to 573 x 10(3) g/mol. Considerable RAW264.7 cell activation was observed by HP1,2,3 with NO production of 34.9, 443 and 42.7 mu M, respectively, as well as the mRNA expression of cytokines (IL-1 beta, IL-6, IL-10 and IL-12). NK cell cytotoxicity against HT-29 cell was facilitated by OS1,2,3 treatment with the increased gene expressions of INF-gamma, Granzyme-B, perforin, NKG2D, and FasL. RAW264.7 cells appeared to be activated via MR and TLR4 mediated signaling pathway, but CR3 and TRL2 might play a main role in stimulating NK cells. Overall, the present study suggests the potential application of polysaccharides from P. sibiricum in functional foods and pharmacological industries. (C) 2018 Elsevier B.V. All rights reserved.