Antioxidant Properties of Ethanolic Extracts from Culinary-Medicinal Button Mushroom Agaricus bisporus (J. Lange) Imbach (Agaricomycetideae) Harvested at Different Stages of Maturity

Agaricus bisporus (I. Lange) Imbach (button mushrooms) were harvested at different stages of maturity and the antioxidant properties of their ethanolic extracts were studied. With regard to EC50 values of antioxidant activities determined by the conjugated diene method, fruiting bodies harvested at stages 1, 4, and 5 were more effective than those at stages 2 and 3. All ethanolic extracts showed comparable reducing power and effective scavenging abilities on l,l-diphenyl-2-picrylhydrazyl (DPPH) radicals. EC50 values were 3.85−6.11 mg/mL, 3.49−78 mg/mL, 0.41−.70 mg/mL, and 9.05−6.20 mg/mL for antioxidant activity, reducing power, scavenging ability on DPPH radicals, and chelating ability on ferrous ions, respectively. The major antioxidant components found in ethanolic extracts were total phenols (9.44 to 10.02 mg/g). Contents of total antioxidant components (ascorbic acid, total tocopherols, and total phenols) were associated with EC50 values of chelating ability on ferrous ions (r = 0.927). Overall, ethanolic extracts from fruiting bodies of A. bisporus harvested at different stages of maturity showed effective antioxidant properties.