Triterpenes and Phenolic Compounds from the Fungus : Isolation, Structure Determination and Biological Activity.

Investigation of the methanol extract of the poroid fungus resulted in the isolation of a novel triterpene, fuscoporic acid (), together with inoscavin A and its previously undescribed isomer ( and ), 3,4-dihydroxy-benzaldehide (), osmundacetone (), senexdiolic acid (), natalic acid (), and ergosta-7,22-diene-3-one (). The structures of fungal compounds were determined on the basis of NMR and MS spectroscopic analyses, as well as molecular modeling studies. Compounds , - were examined for their antibacterial properties on resistant clinical isolates, and cytotoxic activity on human colon adenocarcinoma cell lines. Compound was effective against Colo 205 (IC 11.65 ± 1.67 µM), Colo 320 (IC 8.43 ± 1.1 µM) and MRC-5 (IC 7.92 ± 1.42 µM) cell lines. Potentially synergistic relationship was investigated between and doxorubicin, which revealed a synergism between the examined compounds with a combination index (CI) at the 50% growth inhibition dose (ED) of 0.521 ± 0.15. Several compounds ( and -) were tested for P-glycoprotein modulatory effect in Colo 320 resistant cancer cells, but none of the compounds proved to be effective in this assay. Fungal metabolites - were evaluated for their antioxidant activity using the oxygen radical absorbance capacity (ORAC) and DPPH assays. Compounds and were found to have a considerable antioxidant effect with EC 0.25 ± 0.01 (DPPH) and 12.20 ± 0.92 mmol TE/g (ORAC) The current article provides valuable information on both the chemical and pharmacological profiles of , paving the way for future studies with this species.