Comparative studies on the structure, biological activity and molecular mechanisms of polysaccharides from Boletus aereus (BA-T) and Pleurotus cornucopiae (PC-1)

Abstract

In this study, two new polysaccharides were extracted from the fruiting bodies of Boletus aereus and Pleurotus cornucopiae, respectively. The results of structure identification showed that BA-T was composed of xylose residues, glucose residues and galactose residues, and the ratio is 3:6:6. The BA-T takes 1,6-glucose and 1,6-galactose as skeletons, extends a branched chain from galactose 2-O to connect 1,4-xylose, and connects β-4-glucose terminal monosaccharide to xylose. PC-1 was composed of of xylose, glucose and galactose in the ratio of 2:8:2 and takes 1,6-glucose as skeletons, extends a branched chain from galactose 4-O to connect (1→4,,6)-α-D-Glcp and (1→2,6)-α-D-galactose, and →4)-β-D-Glcp and →1)-α-D-Xylp as terminal group. The results of immunoactivity showed that BA-T and PC-1 have the proliferation activity of B cells, T cells and RAW264.7 cells in vitro, and the effect of BA-T on the proliferation of T cells was the greatest. The results of RNA-sequencing showed that the protein synthesis and metabolism of T cells are more vigorous under the stimulation of BA-T, and oxidative phosphorylation is the main energy source in the process of T cell proliferation.

Keywords:
Boletus aereus ; Pleurotus cornucopiae ; structure identification; immune activity; molecular mechanism