Bioactive terpenes from Spongia officinalis.

The terpene metabolite pattern of Mediterranean Spongia officinalis was chemically investigated. This study resulted in the isolation of a series of sesterterpenes and C21 furanoterpenes, according to the literature data on this sponge. Four new oxidized minor metabolites (compounds 1, 2, 3, and 4) were isolated along with six known compounds of the furospongin series (compounds 5-8, 9, and 10) and three scalarane sesterterpenes (compounds 11-13). Interestingly, tetrahydrofurospongin-2 (6) and dihydrofurospongin-2 (7), which were among the main metabolites, induced biofilm formation by Escherichia coli. All compounds isolated were also assayed for antibacterial and antifungal properties.