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Biodiversity is my main research focus and that of my research group. We study a range of different aspects concerning biodiversity, such as the impact anthropic activities have on biodiversity and how to improve its preservation, its use as a valuable resource for the extraction of bioactive molecules, and the study of its distribution. The research group has over twenty years of experience in the study of zoology, and, more in particular, the immune and behavioural responses of aquatic invertebrates and fish. For many years, the group has observed the effects of various anthropogenic activities, such as the acoustic and chemical impacts on the physiological and behavioral responses of invertebrate organisms, such as Arbacia lixula and Mytilus galloprovincialis, and of fishes, such as Sparus aurata, evaluating not only adult stage but also embryonic stage [1,2]. From a sustainable development perspective, we have recently turned our attention to an evaluation of the nutritional potential of aquaculture species which are recent additions to farming in Sicily: Cherax quadricarinatus and Cherax destructor [3]. However, biodiversity, as well as needing our protection, is also a resource which we can seek to harness in an eco-sustainable way. In recent years, research in our group has focused on the extraction of bioactive molecules from invertebrates and vertebrate living organisms (including from waste from the processing industry), with evident antimicrobial, anticancer and food preservation potential [4]. Last but not least, the regenerative capacities of invertebrate organisms such as Holothuria tubulosa [5] were evaluated with the possibility of transferring this knowledge to the biomedical sector. In addition to carrying out the aforementioned research, we are currently working on a nationally funded PON research project to conduct a freshwater biodiversity census in Palermo, including environmental DNA evaluation.

Marine species represent a rich source of biologically active products that can be used in various fields. Among them, marine algae produce numerous secondary metabolites responsible for different biological activities such as: immunomodulatory [1], antioxidant [2], and antimicrobial [3]. The aim of this study was chemically characterizing the extracts of three macroalgae species: Carpodesmia crinite (Duby) Orellana & Sansón, 2019, Carpodesmia brachycarpa (J. Agardh) Orellana & Sansón 2019, Asparagopsis taxiformis (Delile) Trevisan 1845 and evaluate their biological activities. The characterization of the secondary metabolites was performed by HPLC-MS and the results obtained showed higher meroterpenoids levels. Moreover, the extracts tested against the Arbacia lixula sea urchin modulate the total and differential cellular count demonstrating their involvement in immunity responses. Furthermore, important antimicrobial activities were observed by testing these extracts against the bacterial strains Listeria monocytogenes and Staphylococcus aureus. For the first time our study shows the effects of macroalgae extracts on the immunomodulatory activity in Arbacia lixula sea urchin and important antimicrobial activity. The results obtained, although preliminary, are certainly encouraging and our purpose is also improved this information performing biochemical and molecular assays of extracts obtained to understand better the potential that these metabolites have towards the sea urchin Arbacia lixula that graze on these macroalga.

Inflammation is a complex reaction of host defence mechanisms aiming at neutralization of an insult and restoring normal tissue structure and function. In human IL-17 is T-cell derived cytokine plays a key role in the clearance of extracellular bacteria promoting cell infiltration and production of several cytokines and chemokines. Here, we report on three Ciona intestinalis IL-17 homologues (CiIL17-1, CiIL17-2, CiIL17-3). The gene organization, phylogenetic tree and modeling supported the close relationship with the mammalian IL-17A and IL-17F suggesting that the C. intestinalis IL-17 genes share a common ancestor in the chordate lineages. Real time PCR analysis showed a prompt expression induced by LPS inoculation showing that they are involved in the first steps of inflammatory response. In situ hybridization assays disclosed that the genes transcription was upregulated in the pharynx, the main organ of the ascidian immune system, and expressed by hemocytes (granulocytes and univacuolar refractile granulocyte) inside the pharynx vessels. As in human, we can assume that CiIL-17-like stimulates the release of CiTNFalpha, which synergizes with CiIL-17 in its effects on cells and molecules of Ciona intestinalis immunity system. In addition, a comparative evaluation with others molecules upregulated by LPS challenge as CiTNF-alpha, phenoloxisases, peroxinectin, galectins and mannan binding lectin, have been evaluated in terms of temporal and quantitative gene expression.

The MD2 (Myeloid Differentiation factor-2) protein belongs to the ML superfamily. This group of proteins contain a specific lipid binding domain (ML domain) that plays an important role in lipid recognition and metabolism. In vertebrates, MD-2 is involved in innate immune response as co-receptor in the LPS/TLR4 signaling pathway; MD2 recognizes and binds the bacterial lipid A and drives the TLR4 activation. Two TLR isoforms, CiTLR-1 and CiTLR-2, were identified in Ciona intestinalis with a TIR domain most similar to human TLR4 and TLR 6 respectively. Using a PCR-based subtractive hybridization strategy for isolation of differentially expressed genes between LPS-challenged and naïve C. intestinalis, we identified a full-length cDNA (855 bp) encoding for a 150 a.a. protein (CiMD-2-like). In silico analysis showed that the deduced protein contains a signal peptide (1-19 a.a.) and an E1/Der p2/Der f2/ML domain-MD2 related lipid recognition domain (21-148 a.a) with similarities to ML(MD-2 related Lipid-recognition) domain identified in MD-2 and NPC2 (Niemann-Pick disease type C2). Phylogenetic and structural analysis supported the close relationship with MD-2 and NPC2 suggesting that CiMD-2-like originated from a common ancestor gene. Furthermore, gene expression studies by Real-time PCR demonstrated that this cDNA is up-regulated after LPS injection in the body wall. In situ hybridization performed in controls and LPS-induced animals has shown that this gene is expressed in granular amebocytes, large granules hemocytes and URG (univacuolar refractile granulocyte) in pharynx, the main organ of the ascidian immune system