beta-(1 -> 3)-Glucan of the Southern Bracket Mushroom, Ganoderma australe (Agaricomycetes), Stimulates Phagocytosis and Interleukin-6 Production in Mouse Peritoneal Macrophages

摘要

Ganoderma australe was studied to determine the composition of the cell wall, and polysaccharide fraction SK5 was obtained after freeze-thawing an aqueous 5% potassium hydroxide extraction. The monosaccharide composition of the SK5 fraction revealed by gas chromatography-mass spectrometry showed 81.3% glucose, and analyses by C-13 nuclear magnetic resonance spectroscopy confirmed a beta-glucan with glycosidic links of the (1 -> 3)-beta type and most likely 4-O substituted. In addition, the biological effect of the beta-glucan from G. australe was evaluated via in vitro cell cultures of peritoneal macrophages isolated from Swiss mice. Biological assays were assessed for toxicity and cell activation, interleukin-6 cytokine concentrations, and the ability to stimulate phagocytic activity. There was an increase in interleukin-6 by approximately 111% with 1.0 mu g/mL of polysaccharide, and phagocyte activity was increased in all concentrations examined, obtaining 52.3% with 0.25 mu g/mL polysaccharide. The results indicate that a beta-(1 -> 3)-glucan isolated from G. australe can be classified as a biological response modifier.