The Isolation and Structure Elucidation of Isomalabaricane Triterpenoids Isolated from Marine Sponge Rhabdastrella globostellata collected in Bohol, Philippines

Abstract

The growth inhibitory activity screening of Tropical sponge extracts revealed that the crude extract of Rhabdastrella globostellata colleted in Bohol, The Philippines, efficiently inhibits the growth of human leukemia cell line (K562, IC50 values 0.8μg/mL). Natural products contained in this extract were investigated, in order to discover the cytotoxic metabolite, which resulted in the isolation of isomalabaricane triterpenoids - stellettin A, B, isogeoditin A, 13(E)-isogeoditin A, and geoditin A. The growth inhibitory activities of the isolated compounds against several cancer cell lines are now under investigation.values 0.8μg/mL). Natural products contained in this extract were investigated, in order to discover the cytotoxic metabolite, which resulted in the isolation of isomalabaricane triterpenoids - stellettin A, B, isogeoditin A, 13(E)-isogeoditin A, and geoditin A. The growth inhibitory activities of the isolated compounds against several cancer cell lines are now under investigation.