Analysis of chemical composition, structure of Grifola frondosa polysaccharides and its effect on skin TNF-α levels, lgG content, T lymphocytes rate and caspase-3 mRNA

The polysaccharide was extracted from Grifola frondosa mushroom. The chemical composition of G. frondosa polysaccharide was analyzed by the gas chromatography–mass spectroscopy (GC–MS). The G. frondosa polysaccharide was found to consist of glucose, mannose and galactose with a molar ratio of 6.5:1:2.6. The structure of G. frondosa polysaccharide was characterized by infrared (IR) spectrum, 1D NMR and 2D NMR spectroscopy. The absorption peaks of 1415 cm−1, 1154 cm−1 and 851 cm−1 suggested the polysaccharide consisted of pyranoside. It was found that G. frondosa polysaccharide was a heteropolysaccharide consisting of the repeating disaccharide unit. Comparing control rats, G. frondosa polysaccharide treatment markedly enhanced skin TNF-α levels, reduced lgG content, T lymphocytes rate and caspase-3 mRNA expression in group 2 rats. Administration of G. frondosa polysaccharide significantly reduced skin levels of TNF-α, increased lgG content, T lymphocytes rate and caspase-3 mRNA expression in groups 3 and 4 rats. In conclusion, G. frondosa polysaccharides are beneficial for those with skin diseases.