Evaluation of Marine Microalga Diacronema vlkianum Biomass Fatty Acid Assimilation in Wistar Rats.

is a marine microalgae for which supposed health promoting effects have been claimed based on its phytochemical composition. The potential use of its biomass as health ingredient, including detox-shakes, and the lack of bioavailability studies were the main concerns. In order to evaluate the microalgae-biomass assimilation and its health-benefits, single-dose (CD1-mice) studies were followed by 66-days repeated-dose study in Wistar rats with the highest tested single-dose of microalgae equivalent to 101 mg/kg eicosapentaenoic acid + docosahexaenoic acid (EPA+DHA).

Production of docosahexaenoic acid by Aurantiochytrium sp. ATCC PRA-276.

The high costs and environmental concerns associated with using marine resources as sources of oils rich in polyunsaturated fatty acids have prompted searches for alternative sources of such oils. Some microorganisms, among them members of the genus Aurantiochytrium, can synthesize large amounts of these biocompounds. However, various parameters that affect the polyunsaturated fatty acids production of these organisms, such as the carbon and nitrogen sources supplied during their cultivation, require further elucidation.

Docosahexaenoic acid at the sn-2 position of structured triacylglycerols improved n-3 polyunsaturated fatty acid assimilation in tissues of hamsters.

In this study, we hypothesized that the incorporation of docosahexaenoic acid (DHA) in tissues will be higher when it is ingested as triacylglycerols (TAG) structured at the sn-2 position, which enhances efficacy and health benefits of dietary DHA n-3 supplementation. Ten-week-old Golden Syrian male hamsters were randomly allocated into 4 dietary groups with 10 animals in each: linseed oil (LSO; control group), fish oil (FO), fish oil ethyl esters (FO-EE), and structured DHA at the sn-2 position of TAG (DHA-SL). After 12 weeks, there were no variations in the hamsters' body composition parameters across dietary groups.

Enhancement of ACE and prolyl oligopeptidase inhibitory potency of protein hydrolysates from sardine and tuna by-products by simulated gastrointestinal digestion.

This work was focused on the study of the bioactive potential of three fish protein hydrolysates, one of them prepared from industrial sardine by-products (head and viscera) and the others from tuna by-products (head, and muscle and viscera). These protein hydrolysates exhibited moderate ability to inhibit Angiotensin Converting Enzyme or ACE (IC50 between 0.24-1.

Fatty acids, mercury, and methylmercury bioaccessibility in salmon (Salmo salar) using an in vitro model: Effect of culinary treatment.

The effect of culinary treatments on the fatty acid profile, mercury (Hg), and methylmercury (MeHg) levels of salmon was studied. The bioaccessibility of fatty acids, Hg, and MeHg in raw and grilled salmon was determined. The most intense thermal treatment (grilling) did not alter the relative fatty acid (FA) profile.

Protein gels and emulsions from mixtures of Cape hake and pea proteins.

Background: Portioning of frozen fish generates by-products such as fish 'sawdust' and cut-offs which can be further processed into protein concentrates and isolates. The objective of the present work was to produce gels and emulsions using recovered Cape hake protein powder (HPP). In previous works, the structures of the gels produced by HPP were found to be strong, with a high rubbery character.

Influence of feeding graded levels of canned sardines on the inflammatory markers and tissue fatty acid composition of Wistar rats.

Canned sardines are a ready-to-use fish product with excellent nutritional properties owing to its high n-3 long-chain PUFA content, mainly EPA (20 : 5n-3) and DHA (22 : 6n-3). The present study aimed to assess the effect of two dosages of canned sardines, recommended for the primary and secondary prevention of human CVD, on the inflammatory marker concentrations and fatty acid composition of erythrocytes and key metabolic tissues (liver, muscle, adipose tissue and brain) in the rat model. Wistar rats were fed a diet containing 11 % (w/w) of canned sardines (low-sardine (LS) diet) and a diet containing 22 % (w/w) of canned sardines (high-sardine (HS) diet) for 10 weeks.

Fractionation of protein hydrolysates of fish and chicken using membrane ultrafiltration: investigation of antioxidant activity.

In this work, chicken and fish peptides were obtained using the proteolytic enzymes α-Chymotrypsin and Flavourzyme. The muscle was hydrolyzed for 4 h, and the resulting peptides were evaluated. Hydrolysates were produced from Argentine croaker (Umbrina canosai) with a degree of hydrolysis (DH) of 25.

Preparation of triacylglycerols rich in omega-3 fatty acids from sardine oil using a Rhizomucor miehei lipase: focus in the EPA/DHA ratio.

The increasing evidence on the differential biochemical effects of eicosapentaenoic acid (EPA)/docosahexaenoic acid (DHA) raises the need of n-3 highly unsaturated fatty acid concentrates with different amounts of these fatty acids. In the present work, physicochemical and enzymatic techniques were combined to obtain acylglycerols, mainly triacylglycerols (TAG), rich in n-3 fatty acids. Sardine oil was obtained by washing sardine (Sardina pilchardus) mince with a NaHCO3 solution, hydrolyzed in a KOH-ethanol solution, and concentrated with urea.

Functional and antioxidative properties of protein hydrolysates from Cape hake by-products prepared by three different methodologies.

Background: The production of fish protein hydrolysates (FPH) is a convenient technology for upgrading fish by-products. The aim of this work was to study three different methods of FPH preparation from Cape hake by-products to improve yield and quality. Functional and antioxidative properties of all FPHs were determined.

Impact of ultrafiltration and nanofiltration of an industrial fish protein hydrolysate on its bioactive properties.

Background: Numerous studies have demonstrated that in vitro controlled enzymatic hydrolysis of fish and shellfish proteins leads to bioactive peptides. Ultrafiltration (UF) and/or nanofiltration (NF) can be used to refine hydrolysates and also to fractionate them in order to obtain a peptide population enriched in selected sizes. This study was designed to highlight the impact of controlled UF and NF on the stability of biological activities of an industrial fish protein hydrolysate (FPH) and to understand whether fractionation could improve its content in bioactive peptides.

HPLC preparation of fish waste hydrolysate fractions. Effect on guinea pig ileum and ACE activity.

The effect of RP-HPLC-purified fractions of fish waste hydrolysates issued from three fish industries was tested on guinea pig ileum in order to examine the presence of opioid molecules. The evaluation of anti-hypertensive activities of whole hydrolysates and fractions were also tested, monitoring the ability of the fraction to inhibit the activity of angiotensin I-converting enzyme involved in hypertension regulation. Sardine autolysate and cod head hydrolysate powder (50 microg) were able to inhibit near 30% of ACE activity, whereas 50 microg of shrimp hydrolysate allows the inhibition of 57% of ACE activity.