Prot. 2022R5JJFC - Turning an environmental threat into an opportunity: the invasive sponge PARAleucilla magna as a source of ecofriendly antiFOULING agents (PARAFOULING)

Marine invasive species are having huge environmental and economic impacts along Italian coasts (1). Some of them contain bioactive metabolites whose effects on the native fauna and flora are the subject of a growing literature (2–7). Among invasive benthic invertebrates, the calcareous sponge Paraleucilla magna commonly occurs as invasive fouler in Italian mussel farms and marinas. The sponge markedly selects mussel shells as its substrate, requiring constant efforts by aquaculture farmers to control its growth (8). The sponge material resulting from the cleaning of mussel rows is generally released at sea and accumulates on the seabed, with harmful effects on the environment. This huge waste material, however, has the potential to be exploited to obtain high added-value products of interest for industrial applications, within a knowledge-based strategy for biomass valorization. Actually, recent studies indicate that the crude ethanolic extract of P. magna could represent an important source of antifouling metabolites (9). This evidence is consistent with the evolution of chemical defense strategies in sessile invertebrates, which protect them from biofoulers. It is a natural solution to control fouling that could be effectively mimicked for engineering applications, towards the development of novel environmental-friendly antifouling paints (10). In this view, the harvesting and industrial exploitation of P. magna to obtain its antifouling components could both reduce its environmental impact in the Mediterranean, and bring economic benefits to local aquaculture farmers and fishermen. However, the active components of the crude extract of P. magna have not been identified yet, since the chemical composition of the sponge is still unknown. This lack of information prevents the selection of the active ingredients most suited for the development of novel antifouling products. A first thrust of the present research proposal is thus to fill the knowledge gap by analyzing the chemical composition of P. magna living along Italian coasts. This preparatory study phase will be conducted at the laboratories of the Institute of Biomolecular Chemistry (ICB) of the Italian National Research Council (CNR), with extensive experience in the study of marine natural products and their ecological role. Purified metabolites will be then tested for their inhibitory activity on the settlement of micro- and macrofoulers both at the Marine Biology Laboratory of the University of Trieste, and at the Stazione Zoologica “A. Dohrn” of Naples, taking advantage of the relevant expertise, infrastructure and instrumentation available at these two excellent institutions operating in the field of marine sciences. To select antifouling agents that could effectively substitute the extremely toxic ones that have been used for long time (11), the active components of P. magna will be also tested for their dose-dependent toxicity in vivo.

Marine invasive species are having huge environmental and economic impacts along Italian coasts (1). Some of them contain bioactive metabolites whose effects on the native fauna and flora are the subject of a growing literature (2–7). Among invasive benthic invertebrates, the calcareous sponge Paraleucilla magna commonly occurs as invasive fouler in Italian mussel farms and marinas. The sponge markedly selects mussel shells as its substrate, requiring constant efforts by aquaculture farmers to control its growth (8). The sponge material resulting from the cleaning of mussel rows is generally released at sea and accumulates on the seabed, with harmful effects on the environment. This huge waste material, however, has the potential to be exploited to obtain high added-value products of interest for industrial applications, within a knowledge-based strategy for biomass valorization. Actually, recent studies indicate that the crude ethanolic extract of P. magna could represent an important source of antifouling metabolites (9). This evidence is consistent with the evolution of chemical defense strategies in sessile invertebrates, which protect them from biofoulers. It is a natural solution to control fouling that could be effectively mimicked for engineering applications, towards the development of novel environmental-friendly antifouling paints (10). In this view, the harvesting and industrial exploitation of P. magna to obtain its antifouling components could both reduce its environmental impact in the Mediterranean, and bring economic benefits to local aquaculture farmers and fishermen. However, the active components of the crude extract of P. magna have not been identified yet, since the chemical composition of the sponge is still unknown. This lack of information prevents the selection of the active ingredients most suited for the development of novel antifouling products. A first thrust of the present research proposal is thus to fill the knowledge gap by analyzing the chemical composition of P. magna living along Italian coasts. This preparatory study phase will be conducted at the laboratories of the Institute of Biomolecular Chemistry (ICB) of the Italian National Research Council (CNR), with extensive experience in the study of marine natural products and their ecological role. Purified metabolites will be then tested for their inhibitory activity on the settlement of micro- and macrofoulers both at the Marine Biology Laboratory of the University of Trieste, and at the Stazione Zoologica “A. Dohrn” of Naples, taking advantage of the relevant expertise, infrastructure and instrumentation available at these two excellent institutions operating in the field of marine sciences. To select antifouling agents that could effectively substitute the extremely toxic ones that have been used for long time (11), the active components of P. magna will be also tested for their dose-dependent toxicity in vivo.