Chemical composition of the mushroom Meripilus giganteus Karst. and bioactive properties of its methanolic extract

•M. giganteus showed to be rich in carbohydrates and proteins, with low fat content.•Tocopherols, five organic acids and three phenolic acids were identified.•M. giganteus extract exhibited antioxidant and antimicrobial activity.•M. giganteus extract reduced cancer cells viability and induced apoptosis.•M. giganteus extract inhibited migration of cancer cells in vitro.

Wild Meripilus giganteus Karst belongs to the order Polyporales, in which some members are known to possess a wide range of pharmacological properties. M. giganteus showed to be rich in carbohydrates (74.49 g/100 g) and proteins (15.94 g/100 g), presenting low fat content (1.51 g/100 g). Chemical composition was determined by using chromatographic techniques. Also, various bioactive compounds were detected including all four tocopherol isoforms with δ- and γ-tocopherols being predominant (123.35 and 77.80 μg/100 g, respectively); five organic acids (oxalic, malic, quinic, citric and fumaric acids) with predominant malic acid (3.17 g/100 g); and three phenolic acids and related compounds (p-hydroxybenzoic, p-coumaric and cinnamic acids; 1010, 2420 and 340 μg/100 g, respectively). M. giganteus methanolic extract exhibited antioxidant activity tested by five different assays with the strongest potential in TBARS assay (EC50 0.31 mg/mL); and antimicrobial activities (MIC/MBC 0.0125-5 mg/mL; MIC/MFC 0.025-0.4 mg/mL). Furthermore, treatment of cervical carcinoma cell line (HeLa) led to reduction in cell's viability in MTT assay (IC50 0.41 mg/mL after 48 h), induced process of apoptosis and inhibited cell's migration in vitro. The analysed extract was not toxic for zebrafish embryos (at 0.5 mg/mL), indicating its biosafety and potential application as a dietary supplement in chemoprevention.