AB prepress abstract  -  doi: 10.3354/ab00671

Preliminary observations of caulerpin accumulation from the invasive Caulerpa cylindracea in native Mediterranean fish species

S. Felline*, E. Mollo, A. Cutignano, L. Grauso, F. Andaloro, L. Castriota, P. Consoli, M. Falautano, M. Sinopoli, A. Terlizzi

*Email: serena.felline@unisalento.it

ABSTRACT: Recent studies have showed that the Mediterranean white sea bream Diplodus sargus has included the invasive green alga Caulerpa cylindracea in its diet. As a result of the novel alimentary habits, the fish accumulates the bioactive algal red pigment caulerpin in its tissues with consequent metabolic and enzymatic alterations. However, this may not be an isolated case: other fish species have been described to feed on C. cylindracea, while the possible accumulation of caulerpin in their tissues were never investigated before. In this report, we analysed stomach contents and caulerpin levels in the native sparid species Spondyliosoma chantarus, Sarpa salpa, and Diplodus vulgaris, and in the scarid Sparisoma cretense, in comparison with the lessepsian siganid Siganus luridus. C. cylindracea was found in the stomachs of all studied fish species, with the only exception of S. cretense, where prey items could not be determined due to the high degree of digestion. Chemical analysis on fish tissues revealed that only S. cantharus and S. salpa accumulated caulerpin, while no traces of the compound were detected in the other species. Despite of intense research efforts on natural products from C. cylindracea, a complete picture of the impact caused by the entering of this alga in the fish diet is far to be elucidated. The identification of the accumulation of caulerpin in other Mediterranean native fish, suggests the need to further research, also in order to assess the possible transfer of such molecules to humans through seafood consumption.