Probing sponge-derived terpenoids for human 15-lipoxygenase inhibitors

A human 15-lipoxygenase (15-HLO) assay has been employed to discover new ma rine-sponge-derived bioactive compounds. Extracts from two different sponge s, Jaspis splendens (order Choristida, family Jaspidae) and Suberea sp. (or der Verongida, family Aplysinellidae), exhibited potent IC50 values of 0.4 and 0.1 mug/mL, respectively. Both are sources of terpenoids, and the forme r is a known source of (+)-jasplakinolide (7), which is inactive as a 15-HL O inhibitor. The terpenoids included (+)-(5S,6S)-subersin (1, IC50 > 100 mu M), (-)-(5R,10R)-subersic acid (2, IC50 = 15 muM), jaspaquinol (3, IC50 = 0 .3 muM), and (-)-jaspic acid (4, IC50 = 1.4 muM). Structure elucidations an d lipoxygenase activity studies of these compounds are reported.