Five selected wild edible mushrooms from Romania (Agaricus bisporus, Pleurotus ostreatus, Cantharellus cibarius, Boletus edulis, and Lactarius piperatus) were investigated for their antioxidant potential using an ABTS spectrophotometric assay. Among the selected mushrooms, B. edulis displayed the highest radical scavenging activity and the greatest phenolic content, measured by the Folin–Ciocalteu reagent method. The total flavonoids were quantified using the aluminum chloride colorimetric method, with the extract of B. edulis being the richest. L. piperatus and B. edulis mushrooms exhibited the strongest antibacterial activity against S. aureus and E. coli. The content of trace elements was determined using an atomic absorption spectrometer, and it was found that K and Mg were the main metals present in all the selected mushroom species. The obtained results suggest that the studied wild edible mushrooms are natural functional matrices, and may have potential to be used as natural antioxidants if they are introduced into the daily diet.

Edible mushrooms are well-known for their nutritional benefits and low energy density. In addition, mushroom extracts contain various bioactive compounds that account for their antioxidant activity; the applied extraction conditions influence the extraction efficiency of such compounds. Therefore, this study investigates the effects of four extractants on the content of polyphenols and antioxidant properties of Boletus edulis and Cantharellus cibarius mushrooms, aiming to optimize the extraction process. Powders of B. edulis and C. cibarius mushrooms were subjected to extraction with acidic water (10% CH₃COOH), ethanol/water/acetic acid (15:76.5:8.5, v/v/v), hexane, and diethyl ether to measure their total phenolic content (TPC), total flavonoid content (TFC), and Trolox equivalent antioxidant capacity (TEAC). Furthermore, the level of individual polyphenolic compounds in these extracts was quantified using an HPLC-DAD-ESI-MS method. Results showed that the type of solvent significantly influenced the TPC and TEAC of mushroom powder but insignificantly influenced the TFC. A very strong positive correlation was found between TPC and TEAC, but no correlation was found between TFC and TEAC or TPC and TFC. Acidic water extracted the highest amount of polyphenolic compounds from these mushroom powders. Therefore, the aqueous extract showed the highest TPC and strongest antioxidant activity. Thus, acidic water is recommended for polyphenol analysis in B. edulis and C. cibarius mushrooms.