5α-Reductase inhibitory activity-guided fractionation of the EtOH extract of the fruiting body of Ganoderma lucidum (LEYSS.:FR.) KARST. (Ganodermataceae), which is called Reishi, or Mannentake in Japan and Lingzhi in China, led to the isolation of two active compounds which were ganoderic acid DM and 5α-lanosta-7,9(11),24-triene-15α,26-dihydroxy-3-one with an IC50 of 10.6 μM and 41.9 μM respectively. A carboxyl group of side chain of ganoderic acid DM is essential to elicit the inhibitory activity because of much less activity of its methyl ester.
2006 The Pharmaceutical Society of Japan