The biologically active constituents of Ganoderma lucidum (Fr.) Karst. Histamine release-inhibitory triterpenes.

Abstract
The MeOH extract of G. lucidum has an inhibitory action on histamine release from rat mast cells. From the physiologically active fraction of the extract, along with the known triterpenes ganoderic acids A and B, 2 new triterpenes were isolated and named ganoderic acids C and D. The structures of ganoderic acid C and D were determined to be 3.beta.,7.beta.,15.alpha.-trihydroxy-11,23-dioxo-5.alpha.-lanost-8-en-26-oic acid and 7.beta.-hydroxy-3,11,15,23-tetraoxo-5.alpha.-lanost-8-en-26-oic acid, respectively. Ganoderic acids C and D inhibited histamine release from rat mast cells. Quantitative analysis of these triterpenes was performed for the purpose of crude drug quality control.