Antimutagenicity and induction of anticarcinogenic phase II enzymes by basidiomycetes

Extracts from Phellinus linteus, Phellinus igniarius, and Agrocybe cylindracea have been tested for their antimutagenic properties against direct-acting mutagens {4-nitro-o-phenylenediamine (NPD) and sodium azide (NaN3)} and indirect-acting mutagens {2-aminofluorene (2-AF) and benzo[a]pyrene (B[a]P)}, using the Salmonella typhimurium tester strains TA 98 and TA 100. In addition, the chemopreventive potentials of these extracts to induce NAD(P)H:quinone oxidoreductase (QR) and glutathione S-transferase (GST) activities and glutathione (GSH) level extracts from the filtrate of the cultured broth of P. linteus, polysaccharide extracts from the cultured broth (PI I) and mycelia (PI II) and water extract of fruiting bodies (PI II) of P. igniarius, and polysaccharide extracts frorn the cultured broth (AC I) and mycelia (AC II) of A. cylindracea showed inhibitory effects on the mutagenic activities induced by the direct-acting mutagens, NPD and NaN3, and the indirect-acting mutagens, 2-AF and B[a]P. QR was induced with PI I, PI II, AC I, and AC II, and GST activity was induced with PL I, PL II, PI I, PI I, PI III and AC I in murine Hepa1clc7 cell culture. In addition, PL I, PL II, PI I, PI II, PI III and AC II increased glutathione level. These results suggest that P. linteus, P. igniarius, and A. cylindracea have antimutagenic activities and may play a role in the prevention of cancer by inducing QR and GST activities and increasing GSH level. (C) 2001 Elsevier Science Ireland Ltd. All rights reserved.