CAULERPA RACEMOSA VAR. CYLINDRACEA AND DIPLODUS SARGUS: A MODEL FOR AN INTEGRATED STUDY OF INVASIVE PEST METABOLITES IMPACT ON MEDITERRANEAN COASTAL MARINE SYSTEMS.

In the Mediterranean Sea, the biological invasion by the green algae Caulerpa racemosa var. cylindracea is maybe the most striking marine sea-bottom landscape change of the last decades. In this paper, we have synthesized the results of 5 years of studies about the C. cylindracea effects on fish of ecological and economic importance, such as the white sea bream Diplodus sargus. We found that a secondary metabolite of C. cylindracea has the potential to enter in trophic chains and accumulate in fish tissues. Ecotoxicological analyses made on tissues of the D. sargus specimens showed alterations of some of main antioxidant systems, such as catalase, glutathione peroxidases and total glutathione, and a significant induction of P450 biotransformation system. We found also that the C. cylindracea based-diet can alter muscle fatty acids composition in the white sea bream by reducing the percentage of polyunsaturated fatty acids (PUFA) of the n-3 and n-6 series, such as eicosapentaenoic (EPA, C20:5), docosahexaenoic (DHA, C22:6) and arachidonic acids (AA, C20:4). On the whole, this work sheds light on an unexplored and critical aspect of biological invasions with implication on the health of both humans and the environment.