Lipid Indexes and Quality Evaluation of Omega-3 Rich Oil from the Waste of Japanese Spanish Mackerel Extracted by Supercritical CO2

Japanese Spanish mackerel (JSM) (Scomberomorus niphonius) is a marine fish species containing health-beneficial polyunsaturated fatty acids (PUFAs). In the present study, the quality of JSM by-products oils extracted by supercritical CO2 (SC-CO2) and organic solvent extraction was compared in terms of physico-chemical properties of the oils. Eicosapentaenoic acid (EPA) is one of the important polyunsaturated fatty acids present in SC-CO2-extracted skin and muscle oil 5.81 ± 0.69% and 4.93 ± 0.06%, respectively. The amount of docosahexaenoic acid (DHA) in SC-CO2-extracted skin and muscle oil was 12.56 ± 0.38% and 15.01 ± 0.28%, respectively. EPA and DHA are considered as important PUFAs for the development of brain function and the prevention of coronary heart diseases. Extracted oils showed considerable antioxidant activity. In the obtained oils, atherogenic index (AI) values varied from 0.72 to 0.93 and thrombogenic index (TI) ranged from 0.75 to 0.92, which is considered an acceptable level. Fatty acid composition, bio potentiality, thermogravimetric, and vitamin D analysis showed that oils extracted from JSM by-products can be a good source of oil for application in food, pharmaceutical and cosmetic industries. Therefore, the present research revealed the potentiality of green valorisation of S. niphonius by-products as a possible sustainable approach for targeting the era of zero waste.

The Functional Properties of Bread Enriched with Essential Fatty Acids

We developed ω-3-enriched bread by adding a liposomal polyunsaturated fatty acids (PUFAs) concentrate to the bread recipe. We determined that subsequent feeding of the ω-3-enriched bread to experimental animals in the alimentary dyslipidaemia state led to normalisation of the lipid profile of the blood serum, with a decrease in the total cholesterol, triglycerides, and low-density and very lowdensity lipoproteins. The high-density lipoproteins, antioxidants, reduced glutathione and glutathione reductase activity index increased compared to the corresponding indicators in animals with alimentary dyslipidaemia that were fed bread without ω-3. The ω-3-enriched bread diet significantly decreased harmful oxidation products (diene conjugates and malondialdehyde) in the blood plasma, erythrocytes and liver. Therefore, the results suggested that bread enriched with ω-3 fatty acids is a functional food with hypolipidaemic action. The results on the total content of fatty acids in lipids from bread samples prepared according to a standard recipe and bread enriched with concentrate showed that the relative content of omega-3 PUFAs in the fortified bread significantly increased by 3.2 times compared to bread without the addition of concentrate. The additive did not change the consumer qualities of the finished product (taste and smell of the bread). Keywords: alimentary dyslipidaemia, antioxidant effect, bread, functional food, lipid profile, ω-3 polyunsaturated fatty acids

Relationship Between Dietary Omega-3 and Omega-6 Polyunsaturated Fatty Acids Level and Sarcopenia. A Meta-Analysis of Observational Studies

Objective: This study investigates the relationship between dietary omega-3 and omega-6 polyunsaturated fatty acids (PUFAs) levels and sarcopenia.Methods: A comprehensive literature search in the databases of PubMed, Web of Science, and Embase (up to July 2021) were conducted to identify the observational studies on the relationship between dietary omega-3 and omega-6 PUFAs level and sarcopenia. The pooled odds ratio (OR) of sarcopenia for the highest vs. lowest dietary omega-3 and omega-6 PUFAs level and the standard mean difference (SMD) of dietary omega-3 and omega-6 PUFAs levels for sarcopenia vs. control subjects were calculated.Results: A total of six studies were identified in this meta-analysis. The overall multi-variable adjusted OR showed that dietary omega-3 PUFAs level was inversely associated with sarcopenia (OR = 0.41, 95% CI: 0.26–0.65; P = 0.0001). Moreover, the overall combined SMD showed that the dietary omega-3 PUFAs level in sarcopenia was lower than that in control subjects (SMD = −0.19, 95% CI: −0.32 to −0.07; P = 0.002). With regard to dietary omega-6 PUFAs level, the overall multi-variable adjusted OR suggested no significant relationship between dietary omega-6 PUFAs level and sarcopenia (OR = 0.64, 95% CI: 0.33–1.24; P = 0.19). However, the overall combined SMD showed that the dietary omega-6 PUFAs level in sarcopenia was slightly lower than that in control subjects (SMD = −0.15, 95% CI: −0.27 to −0.02; P = 0.02).Conclusion: Our results suggested that the dietary omega-3 PUFAs level was inversely associated with sarcopenia. However, current evidence is still insufficient to demonstrate the definite relationship between dietary omega-6 PUFAs levels and sarcopenia. More well-designed prospective cohort studies with the dietary omega-3/omega-6 PUFAs ratio are still needed.

Linking Omega-3 Polyunsaturated Fatty Acids in Natural Diet with Brain Size of Wild Consumers

Omega-3 long-chain polyunsaturated fatty acids (n-3 LC-PUFA) are key structural lipids and their dietary intake is essential for brain development of virtually all vertebrates. The importance of n-3 LC-PUFA has been demonstrated in clinical and laboratory studies, but little is known about how differences in availability of n-3 LC-PUFA in natural prey influence brain development of wild consumers. The numerous consumers foraging on the interface of aquatic and terrestrial food webs can differ substantially in their intake of n-3 LC-PUFA, which may lead to differences in brain development, yet, this hypothesis remains to be tested. Here we use the previously demonstrated shift towards higher reliance on n-3 LC-PUFA deprived terrestrial prey of native brown trout Salmo trutta living in sympatry with invasive brook trout Salvelinus fontinalis to explore this hypothesis. We found that the content of n-3 LC-PUFA in muscle tissues of brown trout decreased with increasing consumption of n-3 LC-PUFA deprived terrestrial prey. Brain volume was positively related to content of the n-3 LC-PUFA, docosahexaenoic acid, in muscle tissues of brown trout. Our study thus suggests that increased reliance on low quality diet of n-3 LC-PUFA deprived subsidies can have a significant negative impact on brain development of wild trout. Our findings are important, because ongoing global change is predicted to reduce the availability of dietary n-3 LC-PUFA across food webs and we showed here a first evidence of how brain of wild vertebrate consumers response to scarcity of n-3 LC-PUFA content in natural prey.

Polyunsaturated Fatty Acids as Prebiotics: Innovation or Confirmation?

The International Scientific Association for Probiotics and Prebiotics (ISAPP), in its last consensus statement about prebiotics, defined polyunsaturated fatty acids (PUFAs) as “candidate prebiotics” due to a lack of complete scientific evidence. Previous studies have demonstrated the ability of microbiota to metabolize PUFAs, although the role of the resulting metabolites in the host is less known. Recent partial evidence shows that these metabolites can have important health effects in the host, reinforcing the concept of the prebiotic action of PUFAs, despite the data being mostly related to omega-6 linoleic acid and to lactobacilli taxon. However, considering that the symbionts in our gut benefit from the nutritional molecules that we include in our diet, and that bacteria, like all living organisms, cannot benefit from a single nutritional molecule, the concept of the “correct prebiotic diet” should be the new frontier in the field of gut microbiota research.

Fish Liver Discards as a Source of Long chain Omega-3 Polyunsaturated Fatty Acids

The intake of omega-3 polyunsaturated fatty acids (PUFA) of the average consumer is generally low and products like fish oils high in omega-3 PUFA have become a popular dietary supplement. There is a need for more sources of omega-3 PUFA to cover the increasing demand. This study investigated whether livers from different lean fish species could be a potential new source of oils rich in omega-3 PUFA. The seasonal variation in lipid content, fatty acid composition, peroxide value and free fatty acid content of livers from cod, hake, ling, coalfish and monkfish was determined and the effect of storage conditions on the fishing vessel (ice vs frozen) was studied. Generally, the lipid content and composition of the livers from the five fish species varied similarly during the two years of sampling period with significantly lower values in spring (March, April) and higher values in fall (November, October). Storage conditions were found to have no significant effect on the quality and oil composition. Monkfish livers were less suitable for production of omega-3 oil due to their lower lipid and EPA content and higher FFA levels. Coalfish had higher fluctuations in oil composition during sampling period, which potentially makes a standardised quality difficult to obtain. Cod, hake and ling were the most suitable species for fish liver oil production.

Polyunsaturated fatty acids inhibit a pentameric ligand-gated ion channel through one of two binding sites

Polyunsaturated fatty acids (PUFAs) inhibit pentameric ligand-gated ion channels (pLGICs) but the mechanism of inhibition is not well understood. The PUFA, docosahexaenoic acid (DHA), inhibits agonist responses of the pLGIC, ELIC, more effectively than palmitic acid, similar to the effects observed in the GABAA receptor and nicotinic acetylcholine receptor. Using photo-affinity labeling and coarse-grained molecular dynamics simulations, we identified two fatty acid binding sites in the outer transmembrane domain (TMD) of ELIC. Fatty acid binding to the photolabeled sites is selective for DHA over palmitic acid, and specific for an agonist-bound state. Hexadecyl-methanethiosulfonate modification of one of the two fatty acid binding sites in the outer TMD recapitulates the inhibitory effect of PUFAs in ELIC. The results demonstrate that DHA selectively binds to multiple sites in the outer TMD of ELIC, but that state-dependent binding to a single intrasubunit site mediates DHA inhibition of ELIC.

Vitamin D and Omega-3 Polyunsaturated Fatty Acids in Type 1 Diabetes modulation

Background: Type 1 diabetes (T1D) is a chronic autoimmune disease that affects people globally. Usually developed during childhood, T1D is characterized by the destruction of pancreatic β-cells due to immune cell attack and the establishment of an inflammatory process. Objective: The study aimed to investigate the effects of vitamin D through its nuclear receptor and the ω-3 polyunsaturated fatty acids (PUFAs) through their lipid derivatives in T1D modulation. Both components exert anti-inflammatory activity and act directly on cells of the immune system, attenuating the destruction of insulin-producing cells. Furthermore, they lead to a better glycemic level, reducing the need for insulin and a normal immune state, such as C-peptide maintenance. Method: Presently, our review highlights the significant studies that evaluated the supplementation of vitamin D and ω-3 PUFAs in humans and animal models in the modulation of T1D. Conclusion: The data collected suggests that supplementation can provide potential benefits, mainly when done early in the diagnosis, since it reduces the need for insulin and the risk of complications generated by the disease.