Effects of solid-state fermentation with three higher fungi on the total phenol contents and antioxidant properties of diverse cereal grains

: Three culinary-medicinal fungi and mushrooms (Agaricus bisporus AS2796, Helvella lacunosa X1 and Fomitiporia yanbeiensis S. Guo & L. Zhou) were individually inoculated into different cereal grains (wheat, rice, oat, corn, millet, quinoa, buckwheat, soybean, pea and sorghum) and the antioxidant properties of fungus-fermented products after solid-state fermentation (SSF) (0, 7, 14, 21, 28 and 35 days; 25°C) were studied. The results showed that the total phenol contents (TPCs) of the fermented cereals varied with fermentation time and the starter organisms. According to the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical scavenging capacity, reducing power, ferrous ion chelating ability and superoxide anion radical scavenging ability of ethanolic extracts from the fungus-fermented products (35 days), it was shown that the antioxidant properties of all the products were significantly stronger than uninoculated grains. It revealed that SSF on cereal grains by dietary fungi is a biotechnological strategy, which may enhance the antioxidant properties of the substrate. The three medicinal mushroom and fungi-fermented products were relatively effective in the antioxidant properties assayed and might be potential antioxidants for application in food products.