Chemical Characterization and Antioxidant Properties of Cell Wall Polysaccharides from Antrodia cinnamomea mycelia

Fungal cell wall is composed of various polysaccharides with different structures and diverse bioactivities. Three polysaccharides coded as mycelia hot water-extracted fraction (AC-MHW), mycelia cold alkali-extracted fraction (AC-MCA) and mycelia hot alkali-extracted fraction (AC-MHA) were isolated and purified from the cell wall of Antrodia cinnamomea mycelia with yields of 3.82%, 39.13%, and 10.05%, respectively. The structure analysis showed that all of these polysaccharides were neutral hetero-polysaccharides with a high DB (degree of branching) value and presented as a spherical conformation in NaNO3 solution (0.1 M). Although with different sugar composition and glycosidic bonds, molecular weights of these polysaccharides were all over 10(7) g/mol. Besides, the results on antioxidant activity and IC50 values indicated that in vitro antioxidant activity of the AC-MCA and AC-MHA were much stronger than AC-MHW, which might be attributed to their greater contents of 1,3-glucosyl residues. It could provide a certain reference for the study and development of Antrodia cinnamomea polysaccharides as ingredients of functional foods.

Automated summary

This study isolated and purified three polysaccharides from the cell wall of Antrodia cinnamomea mycelia, each with different structures and antioxidant activities. Despite variations in sugar composition and glycosidic bonds, all polysaccharides had molecular weights over 10(7) g/mol and exhibited a spherical conformation in NaNO3 solution. The AC-MCA and AC-MHA showed stronger in vitro antioxidant activity compared to AC-MHW, possibly due to their higher content of 1,3-glucosyl residues.