Research Data 1

Polysaccharides from Glycyrrhiza are known to have several bioactive effects. However, the relationship of immune activity and structure of low-molecular-weight purified polysaccharide (GP) originated from Glycyrrhiza remains not entirely cleared. In this work, low molecular weight G. polysaccharides (GP1) were obtained through DEAE cellulose-52 column and sephadex G-100 chromatogram. Physicochemical property analysis indicates that GP1 is the low-weight-molecular polysaccharides (6.5 kDa), mainly composed of glucose (98.59%). The backbone structure of GP1 was determined as→4)-α-D-Glcp-(1→ (58.8%) and →6)-α-D-Glcp-(1→ (9.3%) residues, with branching at O-4 position of →4,6)-α-D-Glcp-(1→ mainly by α-D-Glcp-(1→. Moreover, GP1 had good antioxidant ability, and enhanced the phagocytic ability of macrophages RAW264.7 and increased the secretion of NO and cytokines IL-1β, IL-6 and TNF-α. In vitro simulation experiment showed that GP1 was degraded under the action of intestinal flora, and produced a large number of SCFAs and promoted the proliferation of Lactobacillus, HT002 and Ligilactobacillus. In addition, in vivo experiments showed that GP1 significantly enhanced the immune organ index of mice, repaired the intestinal structure, increased the number of goblet cells, CD4+ and CD8+ T cells, the amount of mucus and cytokines secretion (IL-1β, IL-6 and TNF-α). GP1 also significantly alleviates CTX-induced immunosuppression and intestinal damage by up-regulating TLR2, TLR4 and TLR6 signaling pathways. These findings supplied a foundation for further research on the possible mechanism of low-weight-molecular G. polysaccharide regulation of immune response.