Antioxidant properties of edible basidiomycete Phellinus igniarius in submerged cultures

Dried mycelia and mycelia-free broths produced by submerged cultures of Phellinus igniarius under optimal culture conditions were extracted using methanol and hot water and investigated for antioxidant properties. Methanolic extracts from dried mycelia (MEM) and mycelia-free broth (MEB) showed significant antioxidant properties for all EC(50) values less than 10 mg/mL except for MEB in scavenging effects on DPPH radicals. Hot water extracts from dried mycelia (HWEM) were evidenced by their low EC(50) values (<10 mg/mL) to be effective in reducing power, chelating effect on ferrous ions, and scavenging effect on superoxide anions. alpha-tocopherol was mainly found in MEM and gamma-tocopherol in MEB. Ascorbic acid and total flavonoids were abundant in methanolic extracts (MEM + MEB), whereas total phenols were rich in HWEM. An excellent correlation between contents of total phenols and EC(50) values was accomplished for antioxidant activity (R(2)= 0.996) and chelating ferrous ions ability (R(2)= 0.922).

In our paper, the products by submerged culture of Phellinus igniarius exhibited powerful antioxidant properties. Results told that extracts from fermenting products by P. igniarius might be good sources for antioxidant-related functional foods and pharmaceutical industries.