Structural characterization and anti-inflammatory activity of neutral polysaccharides from American ginseng.

American ginseng, a precious classic herbal medicine, is used extensively in China for life prolongation purpose. This study aimed to elucidate the structure and anti-inflammatory activity of a neutral polysaccharide isolated from American ginseng (AGP-A). Nuclear magnetic resonance in conjunction with gas chromatography-mass spectrometry were used to analyze AGP-A's structure, whereas Raw264.7 cell and zebrafish models were employed to assess its anti-inflammatory activity. According to the results, AGP-A has a molecular weight of 5561 Da and is primarily consisted of glucose. Additionally, linear α-(1 → 4)-glucans with α-D-Glcp-(1 → 6)-α-Glcp-(1→ residues linked to the backbone at C-6 formed the backbone of AGP-A. Furthermore, AGP-A significantly decreased pro-inflammatory cytokines (IL-1β, IL-6 and TNF-α) in Raw264.7 cell model. AGP-A in zebrafish model significantly lower the massive recruitment of neutrophils to the neuromast of the caudal lateral line. Inflammation may be relieved by the AGP-A component in American ginseng based on these results. In conclusion, our study shows the structural characterization, remarkable anti-inflammatory properties of AGP-A and its potential curative efficacy as a safe, valid natural anti-inflammatory medicine.