Structural elucidation and immunomodulatory activity of a neutral polysaccharide from the Kushui Rose (Rosa setate x Rosa rugosa) waste. (15th March 2020) - Wu, Mengqi
Highlights: A novel polysaccharide WSRP-1b was extracted and purified from Kushui rose waste. Chemical features and structural properties of WSRP-1b were systematically studied. The structure of WSRP-1b formed with a glucomannan backbone was characterized. WSRP-1b exhibited immunomodulatory effects on RAW264.7 cells. Abstract: In this present study, the structure and immunomodulatory activity of a novel polysaccharide (WSRP-1b) from Kushui rose ( Rosa setate x Rosa rugosa ) waste were investigated. Structure characterization demonstrated that WSRP-1b had a weight-average molecular weight of 1.11 × 10 4 Da and consisted of glucose (42.6 %), mannose (21.4 %), arabinose (9.9 %), xylose (2.2 %), and galactose (23.9 %). Its backbone was composed of 1, 4-linked α-Glc p, 1, 4-linked β-Glc p, and 1, 4-linked β-Man p, with branches of 1, 4-linked α-Glc p and 1, 4-linked β-Man p substituted at C-6 by 1, 6-linked β-Gal p . The branches mainly contained 1, 5-linked Ara f, terminal arabinose and terminal glucose. Bioactivity assays showed that WSRP-1b had immunomodulatory activity by enhancing phagocytosis of macrophages, increasing production of ROS, NO, cytokines (IL-6, TNF-α), and activating NF-κB signaling pathway. These results suggested that it could be developed as a potential and safe immunomodulatory agent in fields of pharmacological or functional foods.