Immunomodulatory activity of a novel polysaccharide extracted from Huangshui on THP-1 cells through NO production and increased IL-6 and TNF-α expression

Huangshui (HS), the by-product of Chinese Baijiu, has attracted considerable attention due to its nutrient and microbial composition; however, none of the studies has explored the polysaccharides in HS yet. Here, from HS, we isolated a novel polysaccharide, HSP-3, with an average molecular weight of 26.40 kDa. The structure was elucidated based on monosaccharide composition and methylation analysis, NMR, FT-IR, and AFM analysis. It is mainly composed of mannose (46.6%), galactose (17.3%), arabinose (11.2%), glucose (10.5%), xylose (8.2%), fucose (5.2%), and rhamnose (1.0%). The backbone of HSP-3 was made up of -> 2)-beta-D-Manp-(1 -> 2,6)-beta-D- Manp-(1 -> 6)-beta-D-Galp-(1 -> 3,6)-beta-D-Galp-(1 -> 4)-alpha-L-Rhap-(1 -> 3,4)-alpha-L-Rhap-(1 -> . Moreover, stimulation of the production of ROS, NO, TNF-alpha and IL-6, upregulation of the mRNA and protein expression levels of TNF-alpha and IL-6 in THP-1 cells, and enhanced the pinocytic and phagocytic capacities of THP-1 cells exhibited sig-nificant immunomodulatory properties of HSP-3. Altogether, this study suggests that HSP-3 could be used as an active component in functional foods.