Comprehensive chemical profiling and bioactivity assessment of Porodaedalea pini and Phellinus tremulae

Fruiting bodies of the fungi Porodaedalea pini (Brot.) Murrill and Phellinus tremulae (Brot.) A. Ames were collected in the Białowieża Forest (Poland). Morphological identification of the collected fruiting bodies was carried out and genetic tests were performed to confirm the identity of the collected specimens. Methanol extracts for biological activity tests were prepared. The methanolic extracts obtained had a plastic consistency, high viscosity and colors from brown to dark brown. The determination of selected elements in Phellinus extracts was performed by X-ray spectrofluorimetry. Thermal decomposition studies and spectroscopic analysis of the dry fruiting bodies were performed. The content of active substances was examined using GCMS chromatography. GCMS analysis showed that the extracts of the tested species contain many chemical compounds that are characterized by high antioxidant potential. These include, among others, phenolic acids (caffeic acid, p-coumaric acid, ferulic acid, 3-hydroxybenzoic acid). In the extract of P. pini, the content of phenolic acids is higher than in P. tremulae. The P. tremulae extract (83.70+/-1.00%) possesses similar antiradical activity against DPPH• as P. pini extract (80.00+/-0.58%). The extracts were tested for their antimicrobial activity against multi-resistant bacteria. Cytotoxic activity was also tested. Both extracts inhibited the growth of S. aureus 4459 (MIC = 6.25 mg/ml), the clinical strain resistant to erythromycin. Cytotoxicity assessment showed that only the P. tremulae extract significantly decreased HaCaT cell viability by 37% and 42% at concentrations of 400 and 800 µg/ml, respectively.