12.

Bioactive Triterpenes from the Fungus Piptoporus betulinus

Zeyad Alresly, Ulrike Lindequist, Michael Lalk, Andrea Porzel, Norbert Arnold and Ludger A.Wessjohann

Institute of Pharmacy, Ernst-Moritz-Arndt-University Greifswald, Friedrich-Ludwig-Jahn-Strasse 17, D-17489 Greifswald, Germany

Leibniz Institute of Plant Biochemistry, Department of Bioorganic Chemistry, Weinberg 3,06120 Halle/Saale, Germany

Abstract: Phytochemical investigation of the ethyl acetate extract of the fruiting bodies from the basidiomycete Piptoporus betulinus led to the isolation of a new bioactive lanostane triterpene identified as 3 b -acetoxy-16-hydroxy-24-oxo-5α-lanosta-8- ene-21-oic acid (1). In addition, ten known triterpenes, polyporenic acid A (5), polyporenic acid C (4), three derivatives of polyporenic acid A (8, 10, 11), betulinic acid (3), betulin (2), ergosterol peroxide (6), 9,11-dehydroergosterol peroxide (7), and fomefficinic acid (9), were also isolated from the fungus. All isolated compounds were tested for antimicrobial activity against some Gram-positive and Gram-negative bacteria as well as against a fungal strain. The new triterpene and some of the other compounds showed antimicrobial activity against Gram-positive bacteria.

Keywords: Piptoporus betulinus ; triterpenoids; antibacterial activity; iceman “Ötzi”. © 2015 ACG Publications. All rights reserved.