Comparison of the Biological Activity and Constituents in Japanese Ambers

Background/Aim: Kuji amber is an interesting natural source for drug discovery because a new anti-allergic compound, named kujigamberol and several new compounds have been isolatated from it. It was important to evaluate the yield, biological activities and constituents of each methanol extract of Kuji, Iwaki, Choshi, Mizunami and Ube ambers in Japan in order to establish if additional new compounds could be identified in these ambers. Materials and Method: Biological activities of each extract were evaluated using growth-restoring activity of the mutant yeast strain involving Ca2+-signal transduction and inhibition activity of degranulation in rat basophilic leukemia (RBL)-2H3 cells. Constituents of each extract were analyzed by high performance liquid chromatography (HPLC). Results: All ambers except Ube amber have growth-restoring activity against the mutant yeast. Both Kuji and Iwaki ambers inhibited the degranulation of RBL-2H3 cells induced by the calcium ionophore A23187 in a dose dependent manner. The main biologically active compound in Kuji amber, kujigamberol, was also isolated from Iwaki amber and analyzed by mass spectrometry (MS) and nuclear magnetic resonance (NMR). Conclusion: Kuji and Iwaki ambers appeared to have the same origin. Choshi, Mizunami, and Ube ambers are valuable sources for biologically active compounds which are different from those of Kuji amber.