Bioactive Phenolic Compounds of Two Medicinal Mushroom Species Trametes versicolor and Stereum subtomentosum as Antioxidant and Antiproliferative Agents

Abstract Medicinal mushrooms have tremendous potential in production of bioactive compounds with diverse bioactivities while the biochemical potential of some specific mushroom strains (autochthonous for the region) in production of specific bioactive agents may be of the main importance in a continuous search for novel strains with supreme activities all over the world. In this study, the ethanolic (EtOH) and water (H 2 O) extracts of wild‐growing polypore mushroom species were investigated: Trametes versicolor (L.) Lloyd and Stereum subtomentosum Pouzar. This study was designed to determine total phenol (TP), flavonoid (TF) and protein content (TPR) as well as LC/MS/MS phenolic profile related to in vitro antioxidant, antiproliferative (MTT assay) (AP) and DNA fragmentation properties. The H 2 O extracts expressed better antioxidant scavenging potential than EtOH showing the highest activity for the T. versicolor (IC 50 =5.6 μg/mL, IC 50 =0.6 μg/mL for DPPH . and OH . , respectively) while O 2 .− activity achieved the best activity for S. subtomentosum (IC 50 =4.1 μg/mL). In contrary, the highest AP activity was obtained for the EtOH extracts of S. subtomentosum (IC 50 =141.1 μg/mL). The EtOH extracts of both species showed the highest TP, TF and TPR content. Obtained results of DNA degradation indicate genotoxicity potential of the extracts at high concentration. The LC/MS/MS detection showed that the majority of analyzed extracts contained phenolic acids, p‐ hydroxybenzoic and protocatechuic acid. The obtained results suggest that analyzed medicinal mushroom species, T. versicolor and S. subtomentosum , could be of potential interest as new sources of strong natural antioxidants as well as antiproliferative agents in the future.