Fish infectious diseases are one of the main constraints of the aquaculture sector. The use of medicinal plants provides a sustainable way of protection using safe, eco-friendly compounds in a more cost-effective way of treatment, compared to antibiotics. The aim of the present study is the assessment of Artemisia arborescens (AA) feed-supplementation effects on gilthead seabream (Sparus aurata). Fish with an average initial body weight of 109.43 ± 3.81 g, were divided into two groups based on AA feed composition (A25 and A50). Following two months of ad libitum feeding, the effect of diets on fish weight and length were measured. Fish serum and mucus were analyzed for non-specific immune parameters (nitric oxide, lysozyme, myeloperoxidase, protease-/anti-protease activity, and complement), antibody responses, oxidative stress (cytochrome P450 1A1, metallothionein), and metabolism markers (total protein, alkaline phosphatase, and glucose). Expression levels of antioxidants (sod1, gpx1), cytokines (il-1b, il-10, tfgb1, and tnfa), hepcidin, and heat shock protein grp75 genes were measured in spleen samples. A results analysis indicated that A. arborescens use as a feed supplement has a compromised positive effect on the growth performance, immune response, and blood parameters of gilthead seabream. Overall, the suitability of A. arborescens as an efficient food supplement for gilthead seabream health improvement was investigated, setting the basis for its application assessment in Mediterranean aquaculture.

Marine (blue) biotechnology is an emerging field enabling the valorization of new products and processes with massive potential for innovation and economic growth. In the Mediterranean region, this innovation potential is not exploited as well as in other European regions due to a lack of a clear identification of the different value chains and the high fragmentation of business innovation initiatives. As a result, several opportunities to create an innovative society are being missed. To address this problem, eight Northern Mediterranean countries (Croatia, France, Greece, Italy, Montenegro, Portugal, Slovenia and Spain) established five national blue biotechnology hubs to identify and address the bottlenecks that prevent the development of marine biotechnology in the region. Following a three-step approach (1. Analysis: setting the scene; 2. Transfer: identification of promising value chains; 3. Capitalization: community creation), we identified the three value chains that are most promising for the Northern Mediterranean region: algae production for added-value compounds, integrated multi-trophic aquaculture (IMTA) and valorization aquaculture/fisheries/processing by-products, unavoidable/unwanted catches and discards. The potential for the development and the technical and non-technical skills that are necessary to advance in this exciting field were identified through several stakeholder events which provided valuable insight and feedback that should be addressed for marine biotechnology in the Northern Mediterranean region to reach its full potential.

The valorization of aquaculture/fishery processing by-products, as well as unavoidable/unwanted catches and discards in Greece, is currently an underutilized activity despite the fact that there are several best practices in Northern Europe and overseas. One of the main challenges is to determine whether the available quantities for processing are sufficient to warrant the valorization of discards and fish side streams. This is the first attempt to systematically record and analyze the available quantities of fish by-products and discards in Greece spatially and temporally in an effort to create a national exploitation Master Plan for the valorization of this unavoidable and unwanted biomass. A thorough survey conducted within the VIOAXIOPIO project unveiled a substantial biomass of around 19,000 tonnes annually that could be harnessed for valorization. Furthermore, the production of various High-Added-Value Biomolecules (HAVBs) was investigated and experimental trials were conducted to assess the potential yields, with the collected data used to formulate four valorization scenarios.

The valorization of aquaculture/fisheries processing by-products, as well as unavoidable/unwanted catches and discards in Greece is currently an underutilized activity despite the fact that there are several best practices in Northern Europe and overseas. One of the main challenges is to determine whether the available quantities for processing are sufficient to warrant valorization of discards and fish side streams. This is the first attempt to systematically record and analyze the available quantities of fish by-products and discards in Greece in a spatial and temporal way in an effort to create a national exploitation Master Plan for the valorization of this unavoidable and unwanted biomass. A thorough survey conducted within the VIOAXIOPIO project unveiled a substantial biomass of around 19,000 tonnes annually that could be harnessed for valorization. Furthermore, the production of various High Added Value Biomolecules (HAVB) was investigated, and experimental trials were conducted to assess the potential yields and the collected data were used to formulate four valorization scenarios.

Microalgae are a subject of interest not only for fundamental research but for various biotechnological applications as well. In this study, the ability of newly isolated strains, i.e., Picochlorum costavermella VAS2.5, Picochlorum oklahomense SAG4.4, Microchloropsis gaditana VON5.3, and Nephroselmis pyriformis PAT2.7, to grow when cultured in an open raceway pond under laboratory conditions and produce various metabolites of high-added value was evaluated. N. pyriformis PAT2.7 and P. costavermella VAS2.5 were the greatest in biomass production (exceeding 0.4 g/L), while P. costavermella VAS2.5 and M. gaditana VON5.3 were the greatest in lipid production (reaching approximately 18%, wt/wt). The lipid fraction of glycolipids and sphingolipids was predominant (43.6–55.4%, wt/wt), followed by neutral lipids (27.1–50.1%, wt/wt) and phospholipids (6.9–17.4%, wt/wt). Picochlora and M. gaditana VON5.3 lipids were rich in ^{Δ5,8,11,14,17}C20:5 and/or ^Δ9,12,15C18:3, while N. pyriformis PAT2.7 synthesized ^Δ9C16:1 in large quantities (30–40%, wt/wt). All strains showed remarkable yields in polysaccharide and protein production, demonstrated a well-balanced amino acid profile, and synthesized pigments in amounts comparable to other studies. The biochemical profiles of these strains showcased their suitability for use primarily in the aquaculture sector.