Development of friendly antifouling coatings from marine algae

After the ban of TBT-based products, marine paint companies are urged to find an appropriate substitute to prevent biofouling on ship hulls. Biocides commonly used in antifouling paints to replace TBT have caused many doubts about their environmental effects. An alternative is offered by the development of antifouling coatings in which the active ingredients are compounds naturally occurring in marine organisms. Many recent studies confirm a potential for novel active ingredients in antifouling preparations from crude extracts of marine algae. We have shown in our studies that the extracts from Ceramium botryocarpum have an interesting antimicrofouling activity, in comparison with commonly used biocides. In situ tests have been conducted during July and August 2004 in the harbour of Lorient, and the first results of crude extracts incorporated in coatings are promising. The chemical characterization of the extracts is in progress. Further work is now needed to examine the precise role of such antifouling activity in nature, and to determine the specific antimicrobial activity against marine bacteria implicated in biofilms.