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Simple Summary: The aquaculture industry is expected to grow in the coming years, and this means more sustainable ways are urgently needed to feed cultured animals. Insects are a promising ingredient for fish and shrimp aquafeeds, as they can convert agricultural waste into nutritious biomass. However, insect species that are currently commercially available lack some essential nutrients, such as omega-3 fatty acids, necessary for suitably growing marine organisms. We have screened the native wild seaweed fly, Fucellia maritima, to increase current knowledge on the nutritional diversity that insects may add to aquafeeds and for the presence of pathogenic bacteria. We found that these flies have a good amount of healthy fats, including important fatty acids that are beneficial for marine fish. Additionally, they have an acceptable amount of Enterobacteriaceae for animal feed and no presence of Salmonella sp. This finding suggests that Fucellia maritima can be a valuable ingredient for aquafeed formulation, enhancing the growth and overall health of farmed marine animals. World aquaculture is expected to continue to grow over the next few decades, which amplifies the need for a higher production of sustainable feed ingredients for aquatic animals. Insects are considered good candidates for aquafeed ingredients because of their ability to convert food waste into highly nutritional biomass. However, commercially available terrestrial insect species lack n-3 long-chain polyunsaturated fatty acids (LC-PUFAs), which are essential biomolecules for marine cultured species. Nevertheless, several coastal insect species feature LC-PUFAs in their natural fatty acid (FA) profile. Here, we analysed the lipidic profile of wild-caught seaweed fly Fucellia maritima, with a focus on their FA profile, to evaluate its potential to be used as an aquafeed ingredient, as well as to screen for the presence of pathogenic bacteria. Results showed that the flies had a total lipid content of 13.2% of their total dry weight. The main classes of phospholipids (PLs) recorded were phosphatidylethanolamines (PEs) (60.8%), followed by phosphatidylcholine (PC) (17.1%). The most abundant FA was palmitoleic acid (C16:0) with 34.9% ± 4.3 of total FAs, followed by oleic acid (C18:1) with 30.4% ± 2.3. The FA composition of the flies included essential fatty acids (EFAs) for both freshwater fish, namely linoleic acid (C18:2 n-6) with 3.4% ± 1.3 and alpha-linoleic acid (C18:3 n-3) with 3.4% ± 1.9, and marine fish, namely arachidonic acid (C20:4 n-6) with 1.1% ± 0.3 and eicosapentaenoic acid (C20:5 n-3) with 6.1% ± 1.2. The microbiological analysis found 9.1 colony-forming units per gram (CFU/g) of Enterobacteriaceae and no presence of Salmonella sp. was detected in a sample of 25 g of fresh weight. These findings indicate that Fucellia maritima biomass holds the potential to be used as an additional aquafeed ingredient due to its FA profile and the low count of pathogenic bacteria, which can contribute to the optimal growth of fish and shrimp with a low risk of pathogen transfer during the feed production chain. [ABSTRACT FROM AUTHOR]

Ultraviolet B (UVB) radiation induces oxidative stress in skin cells, generating reactive oxygen species (ROS) and perturbing enzyme-mediated metabolism. This disruption is evidenced with elevated concentrations of metabolites that play important roles in the modulation of redox homeostasis and inflammatory responses. Thus, this research sought to determine the impacts of the lipid extract derived from the Nannochloropsis oceanica microalgae on phospholipid metabolic processes in keratinocytes subjected to UVB exposure. UVB-irradiated keratinocytes were treated with the microalgae extract. Subsequently, analyses were performed on cell lysates to ascertain the levels of phospholipid/free fatty acids (GC-FID), lipid peroxidation byproducts (GC-MS), and endocannabinoids/eicosanoids (LC-MS), as well as to measure the enzymatic activities linked with phospholipid metabolism, receptor expression, and total antioxidant status (spectrophotometric methods). The extract from N. oceanica microalgae, by diminishing the activities of enzymes involved in the synthesis of endocannabinoids and eicosanoids (PLA2/COX1/2/LOX), augmented the concentrations of anti-inflammatory and antioxidant polyunsaturated fatty acids (PUFAs), namely DHA and EPA. These concentrations are typically diminished due to UVB irradiation. As a consequence, there was a marked reduction in the levels of pro-inflammatory arachidonic acid (AA) and associated pro-inflammatory eicosanoids and endocannabinoids, as well as the expression of CB1/TRPV1 receptors. The microalgal extract also mitigated the increase in lipid peroxidation byproducts, specifically MDA in non-irradiated samples and 10-F4t-NeuroP in both control and post-UVB exposure. These findings indicate that the lipid extract derived from N. oceanica, by mitigating the deleterious impacts of UVB radiation on keratinocyte phospholipids, assumed a pivotal role in reinstating intracellular metabolic equilibrium. [ABSTRACT FROM AUTHOR]

Modulation of lipid metabolism is a well-established cancer hallmark, and SCD1 has been recognized as a key enzyme in promoting cancer cell growth, including in glioblastoma (GBM), the deadliest brain tumor and a paradigm of cancer resistance. The central goal of this work was to identify, by MS, the phospholipidome alterations resulting from the silencing of SCD1 in human GBM cells, in order to implement an innovative therapy to fight GBM cell resistance. With this purpose, RNAi technology was employed, and low serum-containing medium was used to mimic nutrient deficiency conditions, at which SCD1 is overexpressed. Besides the expected increase in the saturated to unsaturated fatty acid ratio in SCD1 silenced-GBM cells, a striking increase in polyunsaturated chains, particularly in phosphatidylethanolamine and cardiolipin species, was noticed and tentatively correlated with an increase in autophagy (evidenced by the increase in LC3BII/I ratio). The contribution of autophagy to mitigate the impact of SCD1 silencing on GBM cell viability and growth, whose modest inhibition could be correlated with the maintenance of energetically associated mitochondria, was evidenced by using autophagy inhibitors. In conclusion, SCD1 silencing could constitute an important tool to halt GBM resistance to the available treatments, especially when coupled with a mitochondria disrupter chemotherapeutic. [ABSTRACT FROM AUTHOR]

Marine edible macroalgae have functional proprieties that might improve human health and wellbeing. Lipids represent a minor fraction of macroalgae, yet with major interest as main carriers of omega 3 polyunsaturated fatty acids and intrinsic bioactive properties. In this study, we used lipid extracts from the green macroalgae Ulva rigida and Codium tomentosum; the red Gracilaria gracilis,Palmaria palmata and Porphyra dioica; and the brown Fucus vesiculosus, produced in a land-based integrated multitrophic aquaculture (IMTA) system. We determined the lipid quality indices based on their fatty acid profiles and their bioactivities as putative antioxidant, anti-inflammatory and antiproliferative agents. The results reveal to be species-specific, namely U. rigida displayed the lowest atherogenicity and thrombogenicity indices. Palmaria palmata and F. vesiculosus lipid extracts displayed the lowest inhibitory concentration in the free radical scavenging antioxidant assays. Ulva rigida, C. tomentosum, P. palmata and P. dioica inhibited COX-2 activity by up to 80%, while P. dioica and P. palmata extracts showed the highest cytotoxic potential in the MDA-MB-231 breast cancer cells. This work enhances the valorization of macroalgae as functional foods and promising ingredients for sustainable and healthy diets and fosters new applications of high-valued algal biomass, in a species-specific context. [ABSTRACT FROM AUTHOR]