A group from Instituto de Ciências Ambientais, Químicas e Farmacêuticas, Universidade Federal de São Paulo, Brazil, etc. has reported about immune-enhancing activity of polysaccharides from wild mushroom (Gymnopilus imperialis).
https://www.mdpi.com/1424-8247/15/10/1179
In this study, the aqueous extract was obtained from dried basidiomata of G. imperialis, which was fractioned by several steps yielding three main polysaccharide fractions (Gi-MRSW, Gi-FSME, and Gi-FPME) as shown below.
Among those polysaccharides, only the Gi-MRSW fraction displayed immune-enhancing activity on murine macrophages similar to LPS. The detailed molecular structure was not mentioned here.
