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

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

A scoping review of action research in higher education: implications for research-based teaching

Several scholars argue for a closer association between research and teaching in higher education, but it is unclear how research-based teaching can be actualized. Action research (AR) offers designs that position students as actors of the research processes, for example by doing research themselves or co-researching. Therefore, AR and research-based teaching can be considered mutually nested pedagogical and methodological processes. In this scoping review, we explored studies methodologically framed as AR which involve higher education students in the Humanities and Social Sciences as participants. We focused on (1) the research characteristics and (2) how the students were positioned in the identified studies. By reviewing 218 studies in line with inclusion criteria, we found three student positions: students as researchers, as learners and active contributors to research, and as source of information. We discuss implications for teachers/researchers who adopt AR and how they can develop research-based teaching involving students as researchers.publishedVersio

Dental implant treatment in irradiated oral cancer patients. Clinical routines in Norway and a review of the literature

The study seeks to find out if there is a difference in prognosis of primary and secondary dental implantation, i.e. before or after radiotherapy respectively, in cancer patients. We carried out a literature search, as well as investigating if there were different practices at the various hospitals in Norway who perform such treatment

Absorptive capacity as enabler for service improvements − the role of customer satisfaction information usage

Customer satisfaction information (CSI) is of great relevance for customer-oriented and service-led organisations, where customer experience is highly associated with the in-use phase of products and services. This paper explores how firms turn customer satisfaction information into knowledge and actions in a manner that enables service improvements. Based on a study of 24 organisations in six different service sectors, this study investigates CSI usage with respect to absorptive capacity. The paper concludes that efficient CSI usage requires multiple sources of customer satisfaction data that need to be used broadly in the organisation by creating accountability of employees across the organisation, rather than CSI being an issue for the communication function. To release this potential, CSI usage requires mechanisms that reside within the organisation, including ensuring actionability of initiatives, assignment of responsibility for actions and follow up, and providing incentives to mobilise change support. Further, the paper shows that in order to fully understand CSI, research must move beyond focusing on processes and activities to study the underlying capacities needed to release the potential of CSI to serve as a basis for service improvements

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