The crude polysaccharide was obtained from Rosa davurica root via hot water extraction method and ethanol precipi-tation,followed by deproteinization using the Sevage and TCA methods,respectively.After deproteinization,the crude polysac-charide was purified by graded ethanol precipitation method.Herein,the 60%ethanol precipitate was labeled RDRP,and its structure and activity of were further studied.The total sugar content of polysaccharides RDRP was 94.1%,and mainly con-tained a polysaccharide with an average molecular weight of 13.1 kDa with narrow polydispersity at 1.2,as well as comprised of five monosaccharides including glucose,arabinose,galactose,mannose,and xylose.IR spectrum indicate that it was a neu-tral glucopyranoside in the α-configuration.In cyclophosphamide-induced immunosuppressive mice test,the spleen and thy-mus index of mice in each dose group of RDRP were significantly increased(P<0.05,P<0.01),respectively,compared to model group;the white blood cells,red blood cells and platelets in each dose group of RDRP were significantly increased(P<0.05)compared to model group;the immunoglobulin IgG,IgM,IgA and IFN-γ,TNF-α,IL-6 and IL-2 in each dose group of RDRP were significantly increased(P<0.01)compared to model group;the TLR4 and TRAF-6 proteins in each dose group of RDRP were increased significantly(P<0.01),and MyD88 was increased significantly in high-dose group(P<0.01)and showed the increasing trend in other groups;the NF-κB p65 protein also showed the increasing trend in the RDRP groups.Those results implied that the immunomodulatory mechanism of RDRP may be related to the TLR/NF-κB.In this research,the basic structure and immunomodulatory effect and its mechanism of polysaccharide from R.davurica roots were clarified and those data will provide a valuable experimental basis for its development and application.
Rosa davurica rootspolysaccharidestructure characterizationimmunomodulationTLR/NF-κB