Immunomodulatory effect of Cyclocarya paliurus polysaccharide in cyclophosphamide induced immunocompromised mice

•The procedures for separation, extraction and purification of CPP-3 were improved.•CPP-3 (600 mg/kg) significantly increased the spleen and thymus index.•CPP-3 enhanced the activities of SOD, T-AOC, GSH-Px and CAT.•CPP-3 enhanced iNOS, IFN-γ, TNF-α, IL-12 and IL-18 mRNA expression levels.