Antioxidant and antiedema properties of solid-state cultured honey mushroom, Armillaria mellea (higher Basidiomycetes), extracts and their polysaccharide and polyphenol contents.

Culinary-medicinal honey mushroom or Mi-Huan-Ku, Armillaria mellea (AM), is a popular ingredient in the traditional Chinese medicine for treating diseases of geriatric patients. This study aimed to examine the effect of cultured substrates on the mycelial growth of AM and evaluate its antioxidant and antiedema activities as well as its total polysaccharide and polyphenol contents. Results showed that AM grew best on the maize medium and worst on the potato medium. AM ethanol extract (AM-EtOH) showed stronger DPPH radical scavenging activity than AM aqueous extract (AM-H₂O). However, they were weak in metal chelation and reducing power. AM-EtOH but not AM-H₂O at 200 mg/kg showed antiedema activity in rats. The total β-glucan content of AM-H₂O and AM-EtOH was 21.95% and 3.50%, respectively. AM-EtOH showed higher phenol but lower flavonoid content than AM-H₂O. These results indicate that maize is a good source of substrate for mass production of AM mycelia, and its potency of DPPH radical scavenging and antiedema activities was contributed mainly by the phenolic compounds, not the level of polysaccharide content.