Capes-Carolina Foundation (Brazil) for the scholarship of doctoral sandwich (A.A.J. Carneiro), held at the Faculty of Pharmacy, University of Salamanca, Spain in partnership with the Polytechnic Institute of Bragança, Portugal. A.A.J. Carneiro is thankfull to FAPESP and CNPq (Brazil) for financial support and for the scholarship (Brazil). CIMO is grateful to strategic project PEst-OE/AGR/UI0690/2011 for financial support. L. Barros thanks to FCT, POPH-QREN and FSE for her grant (SFRH/BPD/4609/2008). The GIP-USAL is financially supported by the Consolider-Ingenio 2010 Programme (FUN-C-FOOD, CSD2007-00063). M. Dueñas thanks the Spanish “Ramón y Cajal” Programme for a contract.
Several mushroom species have been pointed out as sources of antioxidant compounds, besides their important nutritional value. Agaricus blazei and Lentinus edodes are among the most studied species all over the world, but those studies focused on their fruiting bodies instead of other presentations like powdered preparations used as supplements. In the present work the chemical composition (nutrients and bioactive compounds) and antioxidant activity (free radical scavenging activity, reducing power and lipid peroxidation inhibition) of dried powder formulations of the mentioned mushroom species (APF and LPF, respectively) were evaluated. Powder formulations of both species revealed the presence of essential nutrients such as proteins, carbohydrates and unsaturated fatty acids. Furthermore, they present low fat content (<2 g/100 g) and can be used in low-caloric diets, just like the mushrooms fruiting bodies. APF showed higher antioxidant activity and higher content of tocopherols and phenolic compounds (124 µg/100 g and 770 µg/100 g, respectively) than LPF (32 µg/100 g and 690 µg/100 g). Both formulations might be used as antioxidant sources to prevent diseases related to oxidative stress.