The oyster shell is a residue rich in calcium carbonate, which can be reused as a raw material for creating building materials. For this reason, many researchers focused on the incorporation of oyster shell in the composition of composites, as it is a means of contributing to the economic sustainability by reducing the presence of pollution caused by aquaculture waste in the environment, thus increasing the value chain of the construction sector and reducing its carbon footprint. This paper intends to systematize the scientific production related to oyster shell-based composites in construction, carrying out a search using the Scopus tool and a systematic review based on the PRISMA statement. The results show that research on the incorporation of oyster shell into cementitious mortar mixtures, with a focus on its use in concrete, dominates existing scientific research. There is a lack of studies on the incorporation of the oyster shell that address its application as an aggregate or binder in the composition of coating and laying mortars. Most existing research is from Asia, and there is a lack of research in some parts of Europe. In the Americas, Africa and Oceania, no existing studies were found. Despite the growing understanding of the importance of sustainability and economic issues related to products used in the blue circular economy sector, there are still few studies that consider the incorporation of waste or by-products of aquaculture. Future investigations that cover these practical and contextual gaps can contribute to the better use of oyster shell waste and its insertion in the blue circular economy.

Red king crab and snow crab have both become important species for the Norwegian seafood industry. Since the first commercial harvest of red king crab in 2002 and of snow crab in 2012, the Norwegian seafood industry has developed new technology and knowledge for handling these species. This includes new fishing gear, conditions for live storage and processing, handling of by-products, and entrance into new markets. The total Norwegian quota for red king crab increased from 220 metric tons in 2002 to 2350 metric tons in 2017, with a free-red king crab harvesting zone to the west of the quota-regulated area to prevent further expansion of the crab. At present, there is no established quota for snow crab. In 2016, a volume of about 5300 metric tons of snow crab was landed in Norway. In 2016, the export of red king crab and snow crab in Norway amounted to 529 million and 338 million Norwegian Kroner, respectively. Based on regular surveys of crab populations in the Barents Sea, it is assumed that the volumes red king crab and snow crab will remain steady and increase, respectively. Thus, these industries will continue to be important to the Norwegian seafood industry.

A novel bioactive peptide named τ-AnmTx Ueq 12-1 (short name Ueq 12-1) was isolated and characterized from the sea anemone Urticina eques. Ueq 12-1 is unique among the variety of known sea anemone peptides in terms of its primary and spatial structure. It consists of 45 amino acids including 10 cysteine residues with an unusual distribution and represents a new group of sea anemone peptides. The 3D structure of Ueq 12-1, determined by NMR spectroscopy, represents a new disulfide-stabilized fold partly similar to the defensin-like fold. Ueq 12-1 showed the dual activity of both a moderate antibacterial activity against Gram-positive bacteria and a potentiating activity on the transient receptor potential ankyrin 1 (TRPA1). Ueq 12-1 is a unique peptide potentiator of the TRPA1 receptor that produces analgesic and anti-inflammatory effects in vivo. The antinociceptive properties allow us to consider Ueq 12-1 as a potential analgesic drug lead with antibacterial properties.

Chitin/chitosan and collagen are two of the most important bioactive compounds, with applications in the pharmaceutical, veterinary, nutraceutical, cosmetic, biomaterials, and other industries. When extracted from non-edible parts of fish and shellfish, by-catches, and invasive species, their use contributes to a more sustainable and circular economy. The present article reviews the scientific knowledge and publication trends along the marine chitin/chitosan and collagen value chains and assesses how researchers, industry players, and end-users can bridge the gap between scientific understanding and industrial applications. Overall, research on chitin/chitosan remains focused on the compound itself rather than its market applications. Still, chitin/chitosan use is expected to increase in food and biomedical applications, while that of collagen is expected to increase in biomedical, cosmetic, pharmaceutical, and nutritional applications. Sustainable practices, such as the reuse of waste materials, contribute to strengthen both value chains; the identified weaknesses include the lack of studies considering market trends, social sustainability, and profitability, as well as insufficient examination of intellectual property rights. Government regulations, market demand, consumer preferences, technological advancements, environmental challenges, and legal frameworks play significant roles in shaping both value chains. Addressing these factors is crucial for seizing opportunities, fostering sustainability, complying with regulations, and maintaining competitiveness in these constantly evolving value chains.

The global problem of microbial resistance to antibiotics has resulted in an urgent need to develop new antimicrobial agents. Natural antimicrobial peptides are considered promising candidates for drug development. Echinoderms, which rely on innate immunity factors in the defence against harmful microorganisms, are sources of novel antimicrobial peptides. This study aimed to isolate and characterise antimicrobial peptides from the Edible sea urchin Echinus esculentus. Using bioassay-guided purification and cDNA cloning, three antimicrobial peptides were characterised from the haemocytes of the sea urchin; two heterodimeric peptides and a cysteine-rich peptide. The peptides were named EeCentrocin 1 and 2 and EeStrongylocin 2, respectively, due to their apparent homology to the published centrocins and strongylocins isolated from the green sea urchin Strongylocentrotus droebachiensis. The two centrocin-like peptides EeCentrocin 1 and 2 are intramolecularly connected via a disulphide bond to form a heterodimeric structure, containing a cationic heavy chain of 30 and 32 amino acids and a light chain of 13 amino acids. Additionally, the light chain of EeCentrocin 2 seems to be N-terminally blocked by a pyroglutamic acid residue. The heavy chains of EeCentrocins 1 and 2 were synthesised and shown to be responsible for the antimicrobial activity of the natural peptides. EeStrongylocin 2 contains 6 cysteines engaged in 3 disulphide bonds. A fourth peptide (Ee4635) was also discovered but not fully characterised. Using mass spectrometric and NMR analyses, EeCentrocins 1 and 2, EeStrongylocin 2 and Ee4635 were all shown to contain post-translationally brominated Trp residues in the 6 position of the indole ring.

This study generated bioactive hydrolysates using the enzyme Alcalase and autolysis from mesopelagic fish, including Maurolicus muelleri and Benthosema glaciale. Generated hydrolysates were investigated for their bioactivities using in vitro bioassays, and bioactive peptides were identified using mass spectrometry in active hydrolysates with cyclooxygenase, dipeptidyl peptidase IV and antioxidant activities. In silico analysis was employed to rank identified peptide sequences in terms of overall bioactivity using programmes including Peptide Ranker, PrepAIP, Umami-MRNN and AntiDMPpred. Seven peptides predicted to have anti-inflammatory, anti-type 2 diabetes or Umami potential using in silico strategies were chemically synthesised, and their anti-inflammatory activities were confirmed using in vitro bioassays with COX-1 and COX-2 enzymes. The peptide QCPLHRPWAL inhibited COX-1 and COX-2 by 82.90% (+/−0.54) and 53.84%, respectively, and had a selectivity index greater than 10. This peptide warrants further research as a novel anti-inflammatory/pain relief peptide. Other peptides with DPP-IV inhibitory and Umami flavours were identified. These offer potential for use as functional foods or topical agents to prevent pain and inflammation.