Seaweed is becoming a popular food source due to its high nutritional content, but may also contain potentially toxic elements (PTEs). This study investigates trends in PTEs in several species of seaweed collected in Iceland, and variations between thallus section, location, and season. As (3.8-265 mg kg-1), Cd (0.06-18 mg kg-1) and U (0.03-1.9 mg kg-1) were highest in Phaeophyta collected in February, whilst certain Chlorophyta contained the highest levels of Pb (0.02-1.8 mg kg-1) and Fe (25-13607 mg kg-1). Samples contained high levels of essential trace elements but elevated levels of Cd – 19 samples exceeded the maximum level (3 mg kg-1) in food supplements. As levels were also high where over half of samples exceeded the 40 mg kg-1 ML for As in seaweed-derived animal feed. Certain species grown in Iceland may be prone to high levels of Cd and not be suitable for consumption in large quantities.
Flokkur: Greinar
The short harvesting period of cultivated brown seaweed in Europe can make it difficult for cultivators to produce high quality seaweed biomass all year around. Hence there is a need for novel processing and preservation methods. Acid preservation is a well-known method to preserve food, where the aim is to reduce the pH below 4.5 to inhibit microbial growth. To evaluate the effectiveness of acid preservation, a shelf-life experiment was conducted with Saccharina latissima and Alaria esculenta. The biomass was either treated with lactic- or citric acid and stored for approximately seven months. Physicochemical (including proximate composition, trace minerals, total phenolic content (TPC), texture and pH), microbial-, sensory attributes, and antioxidant (ORAC, DPPH) analyses were performed on the preserved biomass during storage. The proximate composition, color, pH, and texture of the acid-preserved seaweed were relatively stable throughout the storage. However, a decrease was observed in TPC and antioxidant properties (assessed by DPPH) with the acid treatments. Acid preservation is, thus, a good method to stabilize the studied biomass for food and feed applications but less applicable if intended for antioxidant purposes. However, the acid treated biomass might be suitable as an ingredient for a wide range of value-added products.
Atlantic herring Clupea harengus feeding in the Norwegian Sea are assumed to consist of Norwegian spring spawners (NSSH), Icelandic summer spawners (ISSH) and North Sea autumn spawners (NSAH). Putative Norwegian autumn spawners (NASH), Faroese autumn (FASH) and spring (FSSH) spawners also feed in the area.
However, until there is a method to discriminate between populations in mixed samples, fishery and survey data from the Norwegian Sea will be solely attributed to the predominating NSSH, ultimately causing biased stock assessments.
Hence, we evaluated if a panel of 120 single nucleotide polymorphisms (SNPs) associated with spawning characteristics and salinity preferences would be an effective discrimination tool. The overall observed levels of genetic differentiation were high (FST = 0.57, p < 0.001, 95% CI: 0.51−0.62). Spawners from stocks under current management (NSSH, NSAH and ISSH) were well separated, but the putative populations were not. Discriminant analysis of principal component as well as Structure runs confirmed the differentiation observed with FST. When the SNP panels were tested on commercial fishery samples of NSSH east of Iceland, up to 16% were assigned to ISSH.
This implies that catch data are seriously biased and demonstrates the potential of SNP panels as a tool to solve the problem. However, work is needed to develop improved SNP panels that effectively separate the putative populations from the managed stocks. We recommend that such a tool should be established in regular sampling of fishery and surveys in the Norwegian Sea and accounted for in future stock assessments, advice and management.
Dietary vitamin B12 deficiency is one of the most common micronutrient deficiencies worldwide, with over a billion individuals suffering from low levels of the vitamin. While ruminant-derived meat and dairy products play a crucial role in providing the recommended B12 dietary allowance (2.4 μg/day), increasing the production and consumption of meat and milk entails substantial environmental ramifications.
Spirulina blue-green algae (Arthrospira platensis) has been widely proposed as healthier and more sustainable substitutes for meat, milk, and dairy products (also known as meat and milk analogues). However, previous research has shown that while Spirulina contain desirable macro- and micro- nutrients (e.g., essential amino acids, calcium, potassium, magnesium, iron), the majority of vitamin B12 found in so-called traditional Spirulina is a non-active, pseudo-form (cobamide), unavailable to humans, referred to as pseudo-vitamin B12. This renders traditional Spirulina a limited alternative to animal-source foods. As a response, in this exploratory in vitro study, we ask whether light conditions may enhance active vitamin B12 production in Spirulina.
We describe the use of scalable photobioreactors, artificially illuminated, located in the Hengill area of Iceland. These systems are used to cultivate Photosynthetically Controlled Spirulina (PCS), to produce carbon–neutral and nutritious biomass containing unopposed, biologically active vitamin B12, in levels comparable to beef (1.64 μg/100g in PCS with a standard deviation of 5% versus 0.7–1.5 μg/100g in beef ). In terms of mitigating global vitamin B12 deficiency, we explore production scale up scenarios.
In one scenario, by re-allocating the electricity currently consumed by heavy industry, Iceland could pro- duce 277,950 tonnes of Spirulina biomass per year, which translates into approximately 4555 g per year of active vitamin B12, able to meet the recommended dietary allowance (RDA) of over 13.8 million children aged 1–3. More ambitious production scenarios could see Iceland providing the RDA for over 26.5 million children aged 1–3, and over 50 million children aged 0–6 months.
Near-infrared spectroscopy has become a common quality assessment tool for fishmeal products during the last two decades. However, to date it has not been used for active online quality monitoring during fishmeal processing. Our aim was to investigate whether NIR spectroscopy, in combination with multivariate chemometrics, could actively predict the changes in the main chemical quality parameters of pelagic fishmeal and oil during processing, with an emphasis on lipid quality changes. Results indicated that partial least square regression (PLSR) models from the NIR data effectively predicted proximate composition changes during processing (with coefficients of determination of an independent test set at 𝑅2𝐶𝑉RCV2 = 0.9938, RMSECV = 2.41 for water; 𝑅2𝐶𝑉RCV2 = 0.9773, RMSECV = 3.94 for lipids; and 𝑅2𝐶𝑉RCV2 = 0.9356, RMSECV = 5.58 for FFDM) and were successful in distinguishing between fatty acids according to their level of saturation (SFA (𝑅2𝐶𝑉=0.9928, 𝑅𝑀𝑆𝐸𝐶𝑉=0.24)RCV2=0.9928, RMSECV=0.24), MUFA (𝑅2𝐶𝑉=0.8291, 𝑅𝑀𝑆𝐸𝐶𝑉=1.49)RCV2=0.8291, RMSECV=1.49), PUFA (𝑅2𝐶𝑉=0.8588, 𝑅𝑀𝑆𝐸𝐶𝑉=2.11)RCV2=0.8588, RMSECV=2.11)). This technique also allowed the prediction of phospholipids (PL 𝑅2𝐶𝑉=0.8617, 𝑅𝑀𝑆𝐸𝐶𝑉=0.11RCV2=0.8617, RMSECV=0.11, and DHA (𝑅2𝐶𝑉=0.8785, 𝑅𝑀𝑆𝐸𝐶𝑉=0.89) RCV2=0.8785, RMSECV=0.89) and EPA content 𝑅2𝐶𝑉=0.8689, 𝑅𝑀𝑆𝐸𝐶𝑉=0.62)RCV2=0.8689, RMSECV=0.62) throughout processing. NIR spectroscopy in combination with chemometrics is, thus, a powerful quality assessment tool that can be applied for active online quality monitoring and processing control during fishmeal and oil processing.
Tengiliður
Aurélien Daussin
Sérfræðingur
aurelien@matis.is
Microorganisms released into the atmosphere by various disturbances can travel significant distances before depositing, yet their impact on community assembly remains unclear. To address this, we examined atmospheric and lithospheric bacterial communities in 179 samples collected at two distinct Icelandic volcanic sites: a small volcanic island Surtsey, and a volcanic highland Fimmvörðuháls using 16S rRNA amplicon sequencing.
Airborne microbial communities were similar between sites while significant differences emerged in the communities on lava rocks after 1-year exposure. SourceTracker analysis revealed distinct bacterial populations in the atmosphere and the lava rocks with surrounding soil contributed more significantly to lava rock microbial composition. Nevertheless, shared genera among air, rocks, and local sources, suggested potential exchange between these environments. The prevalent genera shared between rocks and potential sources exhibited stress-resistant properties, likely helping their survival during air transportation and facilitating their colonization of the rocks.
We hypothesize that the atmosphere serves as a conduit for locally sourced microbes and stress-resistant distant-sourced microbes. Additionally, bacterial communities on the lava rocks of Fimmvörðuháls showed remarkable similarity after 1 and 9 years of exposure, suggesting rapid establishment. Our study reveals that atmospheric deposition significantly influences bacterial community formation, potentially influencing ecosystem dynamics and microbial communities’ resilience.
A study was conducted in fish processing facilities to investigate the microbial composition, microbial metabolic potential, and distribution of antibiotic resistance genes. Whole metagenomic sequencing was used to analyze microbial communities from different processing rooms, operators and fish products. Taxonomic analyses identified the genera Pseudomonas and Psychrobacter as the most prevalent bacteria. A Principal Component Analysis revealed a distinct separation between fish product and environmental samples, as well as differences between fish product samples from companies processing either Gadidae or Salmonidae fish. Some particular bacterial genera and species were associated with specific processing rooms and operators. Metabolic analysis of metagenome assembled genomes demonstrated variations in microbiota metabolic profiles of microbiota across rooms and fish products. The study also examined the presence of antibiotic-resistance genes in fish processing environments, contributing to the understanding of microbial dynamics, metabolic potential, and implications for fish spoilage.
Tengiliður
René Groben
Verkefnastjóri
rene.groben@matis.is
International agreements recognize the importance of cooperative scientific research to conserve and promote sustainable development of a shared Atlantic Ocean. In 2022, the All-Atlantic Ocean Research and Innovation Alliance Declaration was signed. The All-Atlantic Declaration continues and extends relationships forged by the Galway Statement on Atlantic Ocean Cooperation and the Belém Statement on Atlantic Ocean Research and Innovation Cooperation. These efforts are consistent with programs, actions, and aims of the United Nations Decade of Ocean Science for Sustainable Development. In preparation for implementation of the All-Atlantic Declaration, members of the Marine Microbiome Working Group and the Marine Biotechnology Initiative for the Atlantic under the Galway and Belém Statements respectively, joined forces to call for cooperation across the Atlantic to increase marine microbiome and biotechnology research to promote ocean health and a sustainable bioeconomy. This article reviews the goals of the marine microbiome and biotechnology initiatives under the Galway and Belém Statements and outlines an approach to implement those goals under the All-Atlantic Declaration through a Blue Biotech and Marine Microbiome (BBAMM) collaboration.
Tengiliður
René Groben
Verkefnastjóri
rene.groben@matis.is
Marine microorganisms contribute to the health of the global ocean by supporting the marine food web and regulating biogeochemical cycles. Assessing marine microbial diversity is a crucial step towards understanding the global ocean. The waters surrounding Iceland are a complex environment where relatively warm salty waters from the Atlantic cool down and sink down to the deep. Microbial studies in this area have focused on photosynthetic micro- and nanoplankton mainly using microscopy and chlorophyll measurements. However, the diversity and function of the bacterial and archaeal picoplankton remains unknown. Here, we used a co-assembly approach supported by a marine mock community to reconstruct metagenome-assembled genomes (MAGs) from 31 metagenomes from the sea surface and seafloor of four oceanographic sampling stations sampled between 2015 and 2018. The resulting 219 MAGs include 191 bacterial, 26 archaeal and two eukaryotic MAGs to bridge the gap in our current knowledge of the global marine microbiome.
Tengiliður
René Groben
Verkefnastjóri
rene.groben@matis.is
The North Atlantic Ocean surrounds Iceland, influencing its climate and hosting a rich ecosystem that provides the Icelandic nation with economically valuable marine species. The basis of the Icelandic marine ecosystem consists of communities of diverse microorganisms including bacteria, archaea, and unicellular eukaryotes. While the primary production of Icelandic waters has been monitored since the 50s, there is limited knowledge of the taxonomic and metabolic diversity of the marine microorganisms in Icelandic waters based on molecular techniques. In this study, we conducted annual sampling at four hydrographic stations over several years to characterize marine microbial communities and their metabolic potential. Using 16S ribosomal RNA gene amplicon sequencing and metagenomics, we resolved the microbial community composition on the North and South Shelves of Iceland, analyzed its evolution from 2011 to 2018, identified frequently occurring taxa, and predicted their potential metabolism. The results showed correlations between the marine microbial community profiles and the water masses in spring, between the North and South Shelves of Iceland. The differences in marine microbial diversity appear to be linked to the average seawater temperature in the mixed surface layer at each sampling station which also constrains the relative abundance of photosynthetic microorganisms. This study set a baseline for the marine microbial diversity in Icelandic marine waters and identified three photosynthetic microorganisms – the cyanobacteria Synechococcus and two members of the Chlorophyta clade – as valuable indicator species for future monitoring, as well as for application in ecosystem modeling in context with research on climate change.