Changes in the antioxidative capacity of saithe (Pollachius virens) and shrimp (Pandalus borealis) press juice and muscle during a simulated gastrointestinal digestion.

Sammendrag Reaktive oksygenforbindelser (ROS) brukes ofte som en fellesbetegnelse for frie radikaler og reaktive oksygenforbindelser. Disse produseres kontinuerlig i kroppen. Kroppen har differensierte systemer for å beskytte seg mot skader fra slike forbindelser; antioksidanter. Dersom forholdet mellom ROS og antioksidanter blir høyt, kan det oppstå en tilstand som kalles oksidativt stress. ROS kan reagere med lipider, proteiner og DNA, og dette er satt i sammenheng med sykdommer som kreft, depresjon og åreforkalkning. Fram til i dag har helseeffekten av sjømat i stor grad vært tillagt de lange, umettede fettsyrene. De senere år er også andre bioaktive komponenter i sjømat blitt viet større oppmerksomhet. Frigjøring av peptider med antioksidativ kapasitet, under fordøyelse av proteiner, er temaet for dette arbeidet. Målet med denne oppgaven var å studere betydningen av fordøyelsen for den antioksidative kapasiteten til muskel fra sei og reke, samt den vannløselige fraksjonen i disse. Dette ble gjort ved å bruke en modell av mage- og tarmkanalen, målt ved metodene ORAC (oxygen radical absorbance capacity), FRAP (ferric reducing ability of plasma) og ABTS (2,2´-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) assay. Innledende studier av effekten av den vannløselige fraksjonen fra sei på LDL-oksidasjon ble også gjennomført. Gjennom fordøyelsen på cirka tre timer, økte den antioksidative kapasiteten fram til fasen som simulerte tynntarmen, etter cirka 75 minutter. Målt ved ORAC, var den totale økningen i antioksidativ kapasitet i prøvene etter fullført fordøyelse mellom 3 og 12 ganger. FRAP viste en lignende utvikling i antioksidativ kapasitet gjennom fordøyelsen, som målt ved ORAC, men med signifikant lavere verdier. Resultatene av ABTS-målingene var inkonsekvente og hadde store standardavvik. Innholdet av protein i prøvene korrelerte med den antioksidative kapasiteten målt ved både ORAC og FRAP. Prøver av den vannløselige fraksjonen fra sei, tatt 30 og 75 minutter etter påbegynt fordøyelse, viste hemming av LDL oksidasjon. Denne var dog ikke signifikant. Resultatene målt ved ORAC samsvarte med tidligere publikasjoner. ABTS viste seg ikke å være en egnet metode for å måle antioksidativ kapasitet av proteiner, peptider og aminosyrer i denne modellen hvor pH varierer. ABTS krever derfor videre utvikling før den kan benyttes til slike målinger. Den antioksidative kapasiteten til fordøyd muskel fra sei og reke viste seg å være omtrent 10 ganger høyere enn den antioksidative kapasiteten til den vannløselige fraksjonen.Summary Reactive oxygen species (ROS) are free radicals and non radical oxygen species, produced constantly in the body. The body has differentiated systems to minimize damages from these ROS, namely antioxidants. When the balance between radicals/pro-oxidants and antioxidants shifts in favour of the former, a state called oxidative stress occurs. The oxidants can react with lipids, proteins and DNA and these reactions are linked to diseases like cancer, depression and atherosclerosis. Up until recently, the health aspects of seafood have primarily been linked to the long chained polyunsaturated fatty acids. In the later years, however, other bioactive compounds in seafood have been devoted more attention. Exposure of peptides with antioxidative capacity, after digestion of proteins, has been the topic for this work. The aim of this thesis was to study the impact of digestion on the antioxidative capacity of saithe and shrimp muscle and their water soluble fractions (press juice). This was evaluated with three methods; ORAC (oxygen radical absorbance capacity), FRAP (ferric reducing ability of plasma) and ABTS (2,2´-Azinobis-(3-ethylbenzothiazoline-6-sulfonic acid) assay. Preliminary studies on the capacity of press juice of saithe to inhibit LDL oxidation were also performed. During the gastrointestinal digestion, approximately three hours, the antioxidative capacity increased up until the phase simulating the small intestine, after approximately 75 minutes. The total increase after complete digestion of the samples was between 3- and 12-fold measured by ORAC. The FRAP assay showed a similar trend in the development of the antioxidative capacity as the ORAC assay, only with significantly lower values. The results obtained from the ABTS assay were inconclusive and had high standard deviations. The protein content measured in the samples correlated well with the antioxidative capacity measured both with ORAC and FRAP. The samples of press juice of saithe, collected after 30 and 75 minutes of digestion, showed an inhibition of LDL oxidation. The results were however not significant. The results obtained from the ORAC assay were in accordance with previous publications. The ABTS assay did not prove to be an adequate method to measure antioxidative capacity in proteins, peptides and amino acids in this model with pH variations. ABTS assay therefore needs further development before used for these measurements. The muscle from seafood exhibited approximately ten-fold more antioxidative capacity compared to the press juice

Health benefits of seafood consumption - with special focus on household preparations and bioactivity in animal models

The papers of this thesis are not available in Munin: 1. Jensen, I-J., Larsen, R., Rustad, T. and Eilertsen, K.E.: 'Nutritional content and bioactive properties of wild and farmed cod (Gadus morhua L.)', of Food Composition and Analysis (2013), vol.31:212-216. Available at http://dx.doi.org/10.1016/j.jfca.2013.05.013 2. Jensen, I-J. Dort, J. and Eilertsen, K.E.: 'Proximate composition, antihypertensive and antioxidative properties of the semimembranosus muscle from pork and beef after cooking and in vitro digestion', Meat Science (2014), vol. 96:916-921. Available at http://dx.doi.org/10.1016/j.meatsci.2013.10.014 3. Jensen, I-J., Eystuskard, J., Madetoja, M. and Eilertsen, K.E.: 'The potential of cod hydrolyzate to inhibit blood pressure in spontaneously hypertensive rats', Nutrition Research (2014), vol.34:168-173. Available at http://dx.doi.org/10.1016/j.nutres.2013.11.003 4. Jensen, I-J., Walquist, M., Liaset, B., Elvevoll, E.O. and Eilertsen, K.E.: 'Seafood protein reduce atherosclerotic burden in female apolipoprotein E deficient (apoE-/-) mice fed a Western type high fat diet for 13 weeks' (manuscript)Fish consumption is well acknowledged to reduce risk of cardiovascular disease, the health benefits mainly being associated with EPA and DHA. Increasing evidence, however, demonstrate that also the proteins and other bioactive compounds may be of relevance to human health. This project was initiated in order to examine the nutritional composition and bioactivity related to cardiovascular disease parameters in fish and terrestrial meat protein sources. The aims were limited to i) document differences in nutritional composition and in vitro bioactivity of wild and farmed Atlantic cod, pork and beef, ii) examine the impact of cooking and digestion on the nutrients and in vitro bioactive components and iii) evaluate the effects of different protein sources and bioactive peptides using animal models of hypertension and atherosclerosis. The nutritional contents of cod and terrestrial meats were comparable, the main differences being lower fat content and three times higher taurine content in cod compared to the meats. Traditional household preparations mainly influenced the water content. The exclusively free amino acid taurine was lost correspondingly to the water loss. Cooked cod provided higher angiotensin converting enzyme inhibitory activity compared to cooked meats. Raw pork exhibited higher antioxidative capacity compared to raw beef, while the cooked meats exhibited similar effects after a simulated digestion. The antihypertensive effect of cod hydrolyzate was evaluated in spontaneously hypertensive rats and after 7 days, the blood pressure increase leveled off and stabilized, suggesting some inhibitory activity of the cod hydrolyzate, although not proven significant in this study. The cardioprotective effects of seafood proteins were compared to those of chicken protein in female apolipoprotein-E-deficient mice. The total plaque burden in the aortas of mice fed cod-scallop protein was significantly lower compared to the plaque burden of mice fed chicken protein

The potential of anthocyanin-loaded alginate hydrogel beads for intelligent packaging applications: Stability and sensitivity to volatile amines

pH indicators have emerged as promising tools for real-time monitoring of product freshness and quality in intelligent food packaging applications. However, ensuring the stability of these indicators is critical for practical use. This study aims to evaluate the stability of anthocyanins-loaded alginate hydrogel beads of varying sizes at different temperatures under accelerated light conditions and relative humidity (RH) levels of 53% and 97% during 21 days of storage. Moreover, their sensitivity to the principal spoilage volatiles of muscle food products such as ammonia (NH3), dimethylamine (DMA) and trimethylamine (TMA) was investigated. The half-life of cyanidin-3-glucoside in small hydrogel beads was roughly twice as long as that of the larger beads under accelerated light exposure at 4 °C and they were less likely to undergo noticeable color changes over time. Both sizes of hydrogel beads stored at 97% RH and 4 °C showed color stability over the 21-day period with minimal color variation (|ΔE| ≤ 3). The UV–vis spectra of the purple corn extract exhibited changes across pH 2 to 12, as evidenced by the visible color variations, ranging from pink to green. The limit of detection (LOD) for NH3 was 25 ppm for small beads and 15 ppm for large ones. Both types of beads exhibited similar LOD for DMA and TMA, around 48 ppm. This research showed that alginate hydrogel beads containing anthocyanins from purple corn are a viable option for developing intelligent packaging of muscle foods. Furthermore, the use of hydrogel beads of different sizes can be customized to specific muscle foods based on the primary spoilage compound generated during spoilage

Marine Capture Fisheries from Western Indian Ocean: An Excellent Source of Proteins and Essential Amino Acids

The Republic of Seychelles is located in Western-Central Indian Ocean, and marine capture fisheries play a key role in the country’s economic and social life in terms of food security, employment, and cultural identity. The Seychellois are among the highest per capita fish-consuming people in the world, with a high reliance on fish for protein. However, the diet is in transition, moving towards a Western-style diet lower in fish and higher in animal meat and easily available, highly processed foods. The aim of this study was to examine and evaluate the protein content and quality of a wide range of marine species exploited by the Seychelles industrial and artisanal fisheries, as well as to further to assess the contribution of these species to the daily intake recommended by the World Health Organization (WHO). A total of 230 individuals from 33 marine species, including 3 crustaceans, 1 shark, and 29 teleost fish, were collected from the Seychelles waters during 2014–2016. All analyzed species had a high content of high-quality protein, with all indispensable amino acids above the reference value pattern for adults and children. As seafood comprises almost 50% of the consumed animal protein in the Seychelles, it is of particular importance as a source of essential amino acids and associated nutrients, and as such every effort to sustain the consumption of regional seafood should be encouraged

Climate Performance, Environmental Toxins and Nutrient Density of the Underutilized Norwegian Orange-Footed Sea Cucumber (Cucumaria frondosa)

Low trophic species are often mentioned as additional food sources to achieve broader and more sustainable utilisation of the ocean. The aim of this study was to map the food potential of Norwegian orange-footed sea cucumber (Cucumaria frondosa). C. frondosa contained 7% protein, 1% lipids with a high proportion of polyunsaturated fatty acids, and a variety of micronutrients. The nutrient density scores (NDS) of C. frondosa were above average compared towards daily recommended intakes (DRI) for men and women (age 31–60) but below when capped at 100% of DRI. The concentrations of persistent organic pollutants and trace elements were in general low, except for inorganic arsenic (iAs) (0.73 mg per kg) which exceeded the limits deemed safe by food authorities. However, the small number of samples analysed for iAs lowers the ability to draw a firm conclusion. The carbon footprint from a value chain with a dredge fishery, processing in Norway and retail in Asia was assessed to 8 kg carbon dioxide equivalent (CO2eq.) per kg C. frondosa, the fishery causing 90%. Although, C. frondosa has some nutritional benefits, the carbon footprint or possible content of iAs may restrict the consumption.Climate Performance, Environmental Toxins and Nutrient Density of the Underutilized Norwegian Orange-Footed Sea Cucumber (Cucumaria frondosa)publishedVersio

Suggestions for a systematic regulatory approach to ocean plastics

The research investigates the problems and maps the solutions to the serious threat that plastics pose to the oceans, food safety, and human health, with more than eight million tons of plastic debris dumped in the sea every year. The aim of this study is to explore how to better improve the regulatory process of ocean plastics by integrating scientific results, regulatory strategies and action plans so as to limit the impact of plastics at sea. Adopting a problem-solving approach and identifying four areas of intervention enable the establishment of a regulatory framework from a multi-actor, multi-issue, and multi-level perspective. The research methodology consists of a two-pronged approach: 1. An analysis of the state-of-the-art definition of plastics, micro-, and nanoplastics (respectively, MPs and NPs), and 2. The identification and discussion of loopholes in the current regulation, suggesting key actions to be taken at a global, regional and national level. In particular, the study proposes a systemic integration of scientific and regulatory advancements towards the construction of an interconnected multi-tiered (MT) plastic governance framework. The milestones reached by the project SECURE at UiT - The Arctic University of Norway provide evidence of the strength of the theory of integration and rights-based approaches. The suggested model holds substantial significance for the fields of environmental protection, food security, food safety, and human health. This proposed MT plastic governance framework allows for the holistic and effective organization of complex information and scenarios concerning plastics regulation. Containing a clear definition of plastics, grounded on the precautionary principle, the MT plastic framework should provide detailed mitigation measures, with a clear indication of rights and duties, and in coordination with an effective reparatory justice system

Fraction of Inspired Oxygen During General Anesthesia for Non-Cardiac Surgery:Systematic Review and Meta-Analysis

BACKGROUND: Controversy exists regarding the effects of a high versus a low intraoperative fraction of inspired oxygen (FiO(2)) in adults undergoing general anesthesia. This systematic review and meta‐analysis investigated the effect of a high versus a low FiO(2) on postoperative outcomes. METHODS: PubMed and Embase were searched on March 22, 2022 for randomized clinical trials investigating the effect of different FiO(2) levels in adults undergoing general anesthesia for non‐cardiac surgery. Two investigators independently reviewed studies for relevance, extracted data, and assessed risk of bias. Meta‐analyses were performed for relevant outcomes, and potential effect measure modification was assessed in subgroup analyses and meta‐regression. The evidence certainty was evaluated using GRADE. RESULTS: This review included 25 original trials investigating the effect of a high (mostly 80%) versus a low (mostly 30%) FiO(2). Risk of bias was intermediate for all trials. A high FiO(2) did not result in a significant reduction in surgical site infections (OR: 0.91, 95% CI 0.81–1.02 [p = .10]). No effect was found for all other included outcomes, including mortality (OR = 1.27, 95% CI: 0.90–1.79 [p = .18]) and hospital length of stay (mean difference = 0.03 days, 95% CI −0.25 to 0.30 [p = .84). Results from subgroup analyses and meta‐regression did not identify any clear effect modifiers across outcomes. The certainty of evidence (GRADE) was rated as low for most outcomes. CONCLUSIONS: In adults undergoing general anesthesia for non‐cardiac surgery, a high FiO(2) did not improve outcomes including surgical site infections, length of stay, or mortality. However, the certainty of the evidence was assessed as low