Abstract: To determine the structures of two sesquiterpene compounds isolated from Commiphora opobalsamum, and to investigate its anti-proliferation effect on tumor cell growth. Methods Two sesquiterpenoids were isolated from the resinous exudates of Commiphora opobalsamum. Their structures were established on the basis of physical and chemical properties, and 1H-NMR and 13 Results Structures of two sesquiterpenoids were determined as (1(10)E,2R,4R)-2-methoxy-8, 12-epoxygermacra-1(10), 7, 11-trien-6-one and 2-methoxy-5-acetoxyfuranogermacr-1(10)-en-6-one, respectively. The results of MTT assay showed that both two compounds had an inhibitory effect on proliferation of the hormone-independent prostate cancer cell lines in a concentration-dependent manner. While no significant anti-proliferation activity was observed in colorectal cells exposed to these chemicals at low concentrations. Furthermore, less cytotoxicity of these compounds was shown by using immortalizied liver normal cell line at concentrations tested. Conclusions Two germacrane sesquiterpenoids were identified the structures, and they can significantly inhibit the proliferation of hormone-independent prostate cancer cell growth.

Key words: Myrrh, Germacrane Sesquiterpenoids, Prostate neplasms, Cell lines