Analytical methods applied to the chemical characterization and antioxidant properties of three wild edible mushroom species from Northeastern Portugal

The chemical composition and the antioxidant potential of three species of wild mushrooms from Northeastern Portugal, namely Agaricus albertii, Agaricus urinascens var. excellens, and Pleurotus eryngii, were compared. Standard procedures were followed in the nutritional value evaluation, while chromatographic procedures were used to analyze free sugars, fatty acids, tocopherols, phenolic compounds, and organic acids. To assess the antioxidant potential, reducing power, radical-scavenging activity, and lipid peroxidation inhibition were evaluated. P. eryngii revealed the highest levels of macronutrients, except proteins, as also the highest sugars, tocopherols, and monounsaturated fatty acids contents. A. albertii and A. urinascens var. excellens showed similar macronutrients composition. However, A. albertii revealed the highest content in PUFA and phenolic compounds. P. eryngii revealed the highest reducing power and radical-scavenging activity and A. albertii the highest lipid peroxidation inhibition. This study provides a detailed chemical characterization and antioxidant potential evaluation of three species of wild mushrooms from Portugal not yet previously reported. Thus, this work intended to contribute to the increase of information concerning species of edible mushrooms (directed to the scientific community and general population) as well as contribute to the conservation of these resources as sources of compounds of interest.Fundação para a Ciência e a Tecnologia (FCT, Portugal) and COMPETE/QREN/EU (research project PTDC/AGR-ALI/110062/2009) and to CIMO (strategic project PEst-OE/AGR/UI0690/2011) for financial support. L. Barros also thanks FCT, POPH–QREN, and FSE for her grant (SFRH/BPD/4609/2008)