Anti-fouling activity and toxicity of the Mediterranean alien sponge Klautau, Monteiro & Borojevic, 2004 (Porifera, Calcarea).

Poriferans, as sessile organisms without rigid external covering, use secondary metabolites for protection from predators and fouling organisms. The present study tested the antifouling activity of ethanolic extract of the Mediterranean alien calcareous sponge towards juvenile mussels . Furthermore, toxicity tests on nauplii of brine shrimp and two microalgae strains, sp. and were also conducted A total attachment inhibition of was achieved at a concentration of 400 µg/mL of sponge extract. The 50% mortality of nauplii was recorded at a concentration of 500 µg/mL of ethanolic extract. The growth inhibitory effect on both marine microalgae strains has been registered at a concentration of 300 µg/mL. Our results suggest promising natural antifouling activity and low toxicity of the ethanolic extract of that could be used as antifouling compound.