Salmonid blood is an abundant by-product of the relatively large and growing salmonid industry in Iceland and has recently gained increased interest as a source of diverse valuable compounds. Blood collection has posed a challenge due to the delicate nature of both the blood and the currently most valuable final product of the salmonid industry, the fillets. This study examined the efficiency of partial dry-bleeding Atlantic salmon (Salmo salar) related to blood recovery and its potential effects on fillet quality compared to traditional bleeding. The quality of fillets was assessed based on parameters, including sensory attributes, physiochemical, and microbial properties for both partially dry-bled and traditionally bled salmon. The results indicated that partial dry-bleeding for 4.5 min effectively recovered blood equal to 1–2 % of the live weight of Atlantic salmon, 75 % of which was obtainable in the first minute and 90 % during the first 2 min. Aside from possibly causing a slight increase in gaping in the fillet, partial dry-bleeding neither affected the flesh quality of fresh salmon compared to traditional bleeding nor following prolonged storage on ice post slaughter. These results provide valuable insight into salmon blood collection practices and preservation treatments for its utilization potential as a valuable resource.
Category: Branches
The water scarcity footprint (WSF), carbon footprint, and blue and green water footprints accounting of the aquafeed used in land-based and ocean-based Atlantic salmon (Salmo salar) farming in Iceland in the year 2021 were assessed through a cradle-to-processor-gate attributional Life Cycle Assessment (LCA) study. The main research questions were: 1) What aquafeed ingredients are environmental hotspots? 2) How does the country of origin of certain aquafeed ingredients affect their environmental performance? 3) Are there any environmental trade-offs between WSF and the carbon footprint of aquafeed ingredients production? All plant ingredients of the aquafeed for salmon farming in Iceland are sourced from abroad, making the sector vulnerable to disruptions within the supply chain, dependent on other countries’ natural resources, and responsible for the contributions put on the local water resources of producing countries. The major WSF contributors were maize meal (for land-based salmon farming) and wheat gluten (for ocean-based salmon farming), which were largely sourced from China. Rainwater (green water) is the largest source of irrigation for all plant-based aquafeed ingredients, which could potentially be depriving natural ecosystems of rainwater if land is transformed for agriculture. The carbon footprint of the aquafeed for the land-based and ocean-based salmon farming was largely explained by soybean meal sourced from Brazil, due to the high land-use changes. Future efforts to reduce water use and carbon emissions should be focused on sourcing aquafeed ingredients based on their lowest water and carbon footprints, as well as with national food security aspects in mind.
A novel bacterium, designated 19SA41, was isolated from the air of the Icelandic volcanic island Surtsey. Cells of strain 19SA41 are Gram-stain-negative, strictly aerobic, non-motile rods and form pale yellow-pigmented colonies. The strain grows at 4–30 °C (optimum, 22 °C), at pH 6–10 (optimum, pH 7.5) and with 0–4% NaCl (optimum, 0.5%). Phylogenetic analyses based on 16S rRNA gene sequences showed that 19SA41 belonged to the genus Flavobacterium and is most similar to Flavobacterium xinjiangense DSM 19743T, with a sequence similarity of 96.52%. The new strain contained iso-C15 : 0 (22%) and summed feature 3 (C16∶1ω6c/C16∶1ω7c) (20%) as the predominant fatty acids. The major respiratory quinone was menaquinone-6 (100%). The polar lipid profile consisted of phosphatidylethanolamine and several uncharacterized amino lipids, glycolipids and lipids. The genome of the new strain was 4.01 Mbp, and its G+C content was 33.2 mol%. Based on characterization and comparative results, using a polyphasic taxonomic approach, we propose that the new isolate represents a novel species of the genus Flavobacterium with the name Flavobacterium aerium sp. nov. The type strain is ISCaR-07695T (=DSM 116640T =UBOOC-M-3567T).
This book offers a state-of-the-art analysis on the main challenges facing the aquatic products processing industry. The topics explored are particularly relevant to the issues faced by European consumers and processors, but the information provided within this book can be widely extrapolated.
This book should be helpful for processors, fish traders, consumers, scientists and students. The first chapter is dedicated to the sociological definition of “fish” and consumers’ perceptions. The following chapters deal with the notions of quality sensu lato, biological risks and their control, as well as the risks linked to the pollution of oceans and ecosystems by microplastics. Two types of processes and processed products – smoked fish and surimi products – which are of great economic importance to the European market, are also presented. The process of adding value to co-products, including the “blue biorefinery” and the innovative pH-shift technology are also covered in this book.
Edited by Véronique Verrez-Bagnis
ISBN : 9781789451498
January 2024
Complex microbiomes are part of the food we eat and influence our own microbiome, but their diversity remains largely unexplored. Here, we generated the open access curatedFoodMetagenomicData (cFMD) resource by integrating 1,950 newly sequenced and 583 public food metagenomes. We produced 10,899 metagenome-assembled genomes spanning 1,036 prokaryotic and 108 eukaryotic species-level genome bins (SGBs), including 320 previously undescribed taxa. Food SGBs displayed significant microbial diversity within and between food categories. Extension to >20,000 human metagenomes revealed that food SGBs accounted on average for 3% of the adult gut microbiome. Strain-level analysis highlighted potential instances of food-to-gut transmission and intestinal colonization (e.g., Lacticaseibacillus paracasei) as well as SGBs with divergent genomic structures in food and humans (e.g., Streptococcus gallolyticus and Limosilactobabillus mucosae). The cFMD expands our knowledge on food microbiomes, their role in shaping the human microbiome, and supports future uses of metagenomics for food quality, safety, and authentication.
Sulfation is gaining increased interest due to the role of sulfate in the bioactivity of many polysaccharides of marine origin. Hence, sulfatases, enzymes that control the degree of sulfation, are being more extensively researched. In this work, a novel sulfatase (SulA1) encoded by the gene sulA1 was characterized. The sulA1-gene is located upstream of a chondroitin lyase encoding gene in the genome of the marine Arthrobacter strain (MAT3885). The sulfatase was produced in Escherichia coli. Based on the primary sequence, the enzyme is classified under sulfatase family 1 and the two catalytic residues typical of the sulfatase 1 family—Cys57 (post-translationally modified to formyl glycine for function) and His190—were conserved. The enzyme showed increased activity, but not improved stability, in the presence of Ca2+, and conserved residues for Ca2+ binding were identified (Asp17, Asp18, Asp277, and Asn278) in a structural model of the enzyme. The temperature and pH activity profiles (screened using p-nitrocatechol sulfate) were narrow, with an activity optimum at 40–50 °C and a pH optimum at pH 5.5. The Tm was significantly higher (67 °C) than the activity optimum. Desulfation activity was not detected on polymeric substrates, but was found on GalNAc4S, which is a sulfated monomer in the repeated disaccharide unit (GlcA–GalNAc4S) of, e.g., chondroitin sulfate A. The position of the sulA1 gene upstream of a chondroitin lyase gene and combined with the activity on GalNAc4S suggests that there is an involvement of the enzyme in the chondroitin-degrading cascade reaction, which specifically removes sulfate from monomeric GalNAc4S from chondroitin sulfate degradation products.
Á GAMLÁRSDAG 2020 fundust óvænt nokkrar tómar hnífskeljar (fylking lindýra, Mollusca, flokkur samloka, Bivalvia) í fjöru innst í Hvalfirði. Skeljarnar draga nafn af útlitinu og eru langar, allt að 24 cm, mjóar, þunnar og beittar, og líkjast helst gamaldags rakhnífum. Fyrir fundinn var ekki vitað til þess að áður hefðu fundist hnífskeljar við Ísland, ef frá er talinn fundur tveggja dauðra fáfnisskelja (Ensis magnus) árið 1957 í fjöru í Lónsvík skammt frá bænum Hvalnesi. Eftir fundinn 2020 fannst í febrúar 2021 lifandi samloka í fjörunni við ósa Hafnarár í mynni Borgarfjarðar. Í kjölfar vettvangsferða höfunda og kynningu fyrstu rannsóknarniðurstaðna á Líffræðiráðstefnu haustið 2021, sem leiddu til umfjöllunar í fjölmiðlum um fundina, bárust fleiri tilkynningar um fundi bæði lifandi og dauðra hnífskelja. Þar á meðal í Kollafirði í maí 2019 og Leiruvogi í febrúar 2020. Fundust skeljar allt að 20 cm langar. Þegar þetta er ritað hefur skelin aðeins fundist við suðaustanverðan Faxaflóa. Í norðanverðu Atlantshafi eru þekktar átta tegundir hnífskelja. Þær eru líkar í útliti og getur verið erfitt að greina þær að. Niðurstöður erfðagreiningar lifandi eintaka í rannsókninni sem hér um getur staðfesta að um er að ræða tegundina Ensis terranovensis, sem við nefnum „sindraskel“. Tegundin hefur til þessa einungis fundist við Nýfundnaland á austurströnd Norður-Ameríku, og var þar fyrst greind árið 2012. Ísland er því fyrsta landið þar sem sindraskel finnst utan náttúrulegra heimkynna. Hún hefur sennilega borist hingað sem lirfa í kjölvatni flutningaskipa, jafnvel fyrir rúmum tíu árum ef mið er tekið af stærstu eintökunum sem hér hafa fundist og áætluðum vexti skeljanna. Flutningur sjávarlífvera af mannavöldum út fyrir náttúruleg heimkynni fer vaxandi. Þar sem framandi tegundir ná fótfestu geta þær breytt og/eða valdið skaða á lífríkinu sem fyrir er. Þess vegna er m.a. mikilvægt að fylgjast með útbreiðslu og lifnaðarháttum sindraskeljarinnar hér við land.
Seaweeds (macroalgae) are an attractive resource for diverse microbial- and enzymatic production processes. They are abundant, underutilized, cheap, and rich in carbohydrates, and therefore have the potential to be used as a source of mono- or oligosaccharides, and as substrates for industrial fermentation processes. Many seaweed polysaccharides, including the sulfated polysaccharides ulvan and fucoidan, are however complex and heterogenous in structure, and there are currently few enzymes available to modify them, and understanding of their enzymatic depolymerization remains limited. The present study aimed to identify and characterize robust fucoidanases and ulvan lyases. Metagenomes were obtained from microbial enrichments from an intertidal hot-spring, genes identified that expressed putative fucoidanases and ulvan lyases, and following gene cloning and expression, the respective enzymes were screened for enzymatic activity. Consistent with their origin, the identified protein sequences were considerably divergent from previously characterized enzymes, with a 44 % average maximal sequence identity. In total, the study resulted in the characterization of 10 new fucoidanases (GH107 and GH168 families) and 8 new ulvan lyases (PL24, PL25 and PL40 families). Notably, the new fucoidanases appeared to have functional specificity towards fucoidan containing α-1,3 linked L-fucosyl and several functioned at high temperature. The study contributes a metagenomics-based approach to identify new seaweed polysaccharide degrading enzymes and an increased understanding of the diversity of such enzymes, which may have implications for the realization of biotechnology based valorization of seaweed biomass.
As the global population continues to grow, so does the demand for longer, healthier lives and environmentally responsible choices. Consumers are increasingly drawn to naturally sourced products with proven health and wellbeing benefits. The marine environment presents a promising yet underexplored resource for the cosmetics industry, offering bioactive compounds with the potential for safe and biocompatible ingredients. This manuscript provides a comprehensive overview of the potential of marine organisms for cosmetics production, highlighting marine-derived compounds and their applications in skin/hair/oral-care products, cosmeceuticals and more. It also lays down critical safety considerations and addresses the methodologies for sourcing marine compounds, including harvesting, the biorefinery concept, use of systems biology for enhanced product development, and the relevant regulatory landscape. The review is enriched by three case studies: design of macroalgal skincare products in Iceland, establishment of a microalgal cosmetics spin-off in Italy, and the utilization of marine proteins for cosmeceutical applications.
Seaweed is a great source of biologically active metabolites which could prove interesting in cosmeceutical applications. In this study, seven Icelandic seaweed species (Ascophyllum nodosum, Alaria esculenta, Laminaria hyperborea, Digital Laminaria, Saccharina latissima, Palmaria palmata, and Schizymenia jonssonii) were screened for total polyphenol content, antioxidant properties, and inhibition of skin-degrading enzymes. Antioxidant assays included DPPH (2,2-diphenyl-1-picrylhydrazyl), reducing power, and ORAC (oxygen radical absorbance capacity). In most assays, A. nodosum extracts were the most active. A. nodosum extracts also showed the strongest inhibition of the skin-degrading enzymes elastase and collagenase at low concentrations, demonstrating its skin-protective qualities. To further investigate the activity, A. nodosum was subsequently extracted with solvents with increasing polarity into seven different extracts. Compared to other extracts, the extracts obtained by extraction with acetone and methanol showed the highest activity in all assays. Extracts obtained with room-temperature water and 85 °C water also demonstrated moderate to high activities. The outcomes of this study support the potential utilization of the brown seaweed A. nodosum as a source of natural ingredients in cosmeceuticals.