Chemical constituents of Stereum subtomentosum and two other birch-associated basidiomycetes: an interspecies comparative study.

Metabolites of the wood-rotting fungus Stereum subtomentosum Pouzar (Basidiomycetes, order Russulales, family Stereaceae) occurring on birch (Betula pendula Roth) trees were phytochemically investigated for the first time. Three main metabolite chemotypes present in MeOH extracts of the fruit bodies, viz. steroids, fatty acids, and water-soluble sugars, were fractionated, isolated, and identified by 1D/2D NMR-spectroscopic analyses, NMR data comparisons, and chemical correlations combined with GC/MS experiments.

The anticancer drug ellipticine forms covalent DNA adducts, mediated by human cytochromes P450, through metabolism to 13-hydroxyellipticine and ellipticine N2-oxide.

Ellipticine is an antineoplastic agent, the mode of action of which is considered to be based on DNA intercalation and inhibition of topoisomerase II. We found that ellipticine also forms the cytochrome P450 (CYP)-mediated covalent DNA adducts. We now identified the ellipticine metabolites formed by human CYPs and elucidated the metabolites responsible for DNA binding.