Optimization of protein removal process of Lonicera japonica polysaccharide and its immunomodulatory mechanism in cyclophosphamide-induced mice by metabolomics and network pharmacology

Abstract

In this study, TCA–n-butanol was chosen as the best deproteinization method for Lonicera japonica polysaccharide (LJP) by comparing the polysaccharide retention rate and the protein clearance rate of five different methods. The response surface methodology (RSM) based on the Box–Behnken design (BBD) was used to optimize the deproteinization conditions as follows: TCA: n-butanol = 1: 5.1, polysaccharide solution: (TCA–n-butanol) = 1: 2.8, and shook for 33 min. LJP could promote the thymus and spleen indexes of cyclophosphamide (CTX)-induced immune-deficient mice. Besides, the contents of cytokine interleukin-2 (IL-2) and hemolysin in mice serum were augmented after treatment with LJP. Based on serum metabolomics analysis, a total of 14 metabolites (VIP >1.0, FC >2 or FC <0.5, and p value