Search Results (358)

Environmental temperature is a major ecological factor shaping physiological and molecular evolution in mammals. Fatty acid desaturase genes (FADS1 and FADS2) play essential roles in the biosynthesis of long-chain polyunsaturated fatty acids (PUFAs), which are critical for membrane structure and metabolic regulation. However, their evolutionary responses to climatic variation in wild mammals remain poorly understood. In this study, we analyzed 27 rodent species distributed across diverse climatic regions to investigate the relationship between environmental temperature and the evolutionary rates of the FADS1 and FADS2 genes. Phylogenetic comparative methods, including phylogenetic ANOVA, phylogenetic generalized least squares (PGLS), and branch model analyses, were applied to estimate ω (dN/dS) ratios and assess selection patterns. Branch-site model analyses were further performed to test for episodic positive selection acting on specific codons in low-temperature-associated lineages. Our results showed that species inhabiting lower-temperature environments exhibited significantly higher ω values for both FADS genes compared with those in warmer environments. PGLS analyses revealed consistent negative associations between temperature variables and evolutionary rates, particularly for BIO5, and branch model analyses further indicated elevated ω values in low-temperature-associated lineages relative to background branches. Branch-site analyses detected significant signatures of episodic positive selection in Spermophilus dauricus and Microtus oregoni, with candidate positively selected codons identified in both lineages. Similar temperature-associated evolutionary rate patterns were also observed in expanded mammalian datasets, suggesting a broader cross-taxa trend. Overall, these findings indicate that environmental temperature is associated with heterogeneous evolutionary rate patterns in FADS genes and suggest that lipid metabolism genes may be recurrently influenced by cold-related selective pressures across mammals. Full article

The lipid and fatty acid composition of the little Baikal oilfish (Comephorus dybowskii Korotneff, 1905) was studied to identify the features of its biochemical adaptation to the environmental conditions of Lake Baikal. Multivariate analysis of lipid classes and FA profiles revealed reproducible clustering patterns in both muscle tissue and whole-body samples, indicating the presence of distinct physiological states differing in membrane organization and lipid metabolism. Lipid-class variability was primarily associated with sphingomyelin, cholesterol esters, phosphatidylinositol, and lysophosphatidylcholine, suggesting the coordinated regulation of membrane structure. The fatty-acid profiles were mainly presented by variations in saturated, monounsaturated, and long-chain polyunsaturated fatty acids, with muscle tissues characterized by a relatively longer carbon chain (ACL = 19 vs. 18 I whole body) and unsaturation (UI = 1.98–2.76 vs. 1.64–2.53 in whole body). At the same time, comparative analysis demonstrated low correspondence between lipid and FA profiles, indicating partially independent adaptive mechanisms. The experimental transfer of fish from their natural habitat to controlled conditions resulted in the significant remodeling of both lipid and FA compositions, including increases in acylglycerols, membrane phospholipids, and monounsaturated fatty acids, together with a decline in long-chain n-3 polyunsaturated fatty acids. The results suggest that lipid classes and fatty acids represent complementary but functionally distinct levels of biochemical adaptation contributing to the maintenance of membrane organization and metabolic homeostasis in C. dybowskii, revealing a previously undescribed multi-level organization of lipid-related adaptive responses in this endemic deep-water fish. Full article

Yellowfin tuna heads (YFTH), a major by-product of tuna processing, are rich in lipids and long-chain n-3 polyunsaturated fatty acids. This study developed and optimized an ultrasound-assisted extraction process without exogenous protease addition, termed non-enzymatic ultrasound-assisted extraction (NE-UAE), for recovering yellowfin tuna head oil (YFTO). The term NE-UAE distinguishes this process from the enzyme-assisted comparators and does not denote a different ultrasonic mechanism. A four-factor, three-level Box–Behnken design was used to optimize nominal ultrasonic power, heat-treatment temperature, liquid-to-solid ratio, and ultrasonic treatment time. The predicted local-optimum conditions were 58.3% of the 1000 W rated power (nominal setting, 583 W), 64.0 °C, 3.0 mL/g, and 31 min, respectively, yielding a validated oil recovery of 63.92 ± 0.24%. The NE-UAE oil (NETO) was compared at the process-chain level with oils obtained by papain-, trypsin-, and Alcalase-assisted aqueous extraction. Under the tested conditions, NETO had lower acid value, initial peroxide value, and p-anisidine value, a lighter color, and lower relative abundances of putative oxidation-related electronic-nose marker signals. Polyunsaturated fatty acids comprised 38.39% of total fatty acids in NETO, including 7.43% EPA and 27.13% DHA. During accelerated storage at 60 °C for 14 d, NETO showed lower absolute peroxide values and smaller baseline-corrected increases than the comparator oils. Overall, NE-UAE provided a feasible process option for recovering YFTO with acceptable oil recovery and favorable quality-related characteristics under the specific process conditions and comparator process chains examined in this study. Full article

Endocannabinoids are lipid mediators consisting of esters, amides and ethers of long-chain polyunsaturated fatty acids. In this work, attention was focused on N-arachidonoyl tyrosine (NA-Tyr) and N-arachidonoyl dopamine (NADA), the amides of arachidonic acid with tyrosine and dopamine, respectively. NADA is an endogenous ligand of both type 1 cannabinoid receptors and type 1 vanilloid channel receptors. NADA is considered an endogenous compound with capsaicin-like activity and is distributed in several brain areas. The metabolic fate of endocannabinoids involves numerous enzymatic activities, which are only partially characterized. In particular, the biological activity of these biomolecules is terminated by enzymes with hydrolytic or oxygenase/oxidase activity. As part of this problem, we studied the oxidation of NADA and NA-Tyr mediated by mushroom tyrosinase. Our experimental data show that tyrosinase can oxidize both NADA and NA-Tyr. The oxidation of these biomolecules was also carried out in the presence of cysteine, allowing us to observe the formation of endocannabinoid/endovanilloid adducts with cysteine. These results were derived from chromatographic analyses and mass spectral experiments. During the tyrosinase-mediated oxidation in the presence of cysteine, it was possible to observe the production of a melanin-like pigment. The spectral characteristics of this pigment are consistent with those of pheomelanin, the pigment that contributes to the structure of neuromelanin. While mushroom tyrosinase serves here as a convenient biomimetic model to investigate the oxidative susceptibility of NADA and NA-Tyr, extrapolating these in vitro findings to mammalian physiology requires caution. Nevertheless, considering the neuronal distribution of these precursors and the documented, albeit debated, presence of tyrosinase-like activity in the central nervous system (CNS), these results offer a chemical rationale to further investigate whether similar oxidative pathways occur in vivo and potentially contribute to neurodegenerative mechanisms. Full article

Butter texture is one of the key quality attributes affecting both technological performance and consumer perception. Although the effects of milk composition and fatty acid profile on butter properties have been widely investigated, studies integrating chemical composition, fatty acid profile, instrumental firmness, and sensory texture characteristics in butter produced from different animal species remain limited. This study evaluated the relationships among chemical composition, fatty acid profile, instrumental firmness, and sensory texture attributes of butter produced from cow, sheep, and goat milk. Sheep butter showed the highest total solids and fat contents (86.84 and 85.27 g/100 g), whereas cow and goat butter contained significantly higher water levels (approximately 17.9 g/100 g; p < 0.05). Cow butter was characterised by higher proportions of long-chain saturated fatty acids, particularly palmitic acid (32.39%), and the highest monounsaturated fatty acid content (24.11%). Although instrumental firmness did not differ significantly among butter types (p > 0.05), cow butter exhibited the highest mean firmness value (6.07 N) and the highest sensory firmness score. Goat butter contained elevated levels of short- and medium-chain fatty acids, and the highest polyunsaturated fatty acid content (4.83%), which was associated with lower firmness (3.04 N). Sheep butter exhibited the highest stearic acid content (11.08%), together with greater spreadability and fatty mouthfeel. Principal component analysis provided an exploratory overview of the relationships among compositional, instrumental, and sensory variables and highlighted potential associations between fatty acid composition and butter texture characteristics. Under the conditions of this pilot-scale study, milk origin was associated with distinct compositional and textural profiles of butter. Full article

To address the quality divergence between wild and cage-farmed red sea bream (Pagrus major), we conducted a comparative analysis of their proximate composition, fatty acid and amino acid profiles, and chromatic characteristics across varying size and growth stages. Farmed fish exhibited substantial lipid deposition (peaking at 4.77% in F4), yielding a high relative percentage of n-3 long-chain polyunsaturated fatty acids. In contrast, wild fish maintained a leaner muscle profile (<2.43% lipid) and were uniquely characterized by an elevated abundance of C22:1n-9 (up to 11.52%), distinguishing them from farmed cohorts. Regarding sensory quality, large-sized wild specimens contained significantly higher concentrations of delicious amino acids (DAA, up to 8.83 g/100 g), particularly glycine and alanine, indicating a superior flavor profile. Colorimetric analysis demonstrated that wild fish maintained vivid reddish pigmentation in the caudal fin (a* = 8.73), whereas farmed fish exhibited marked skin darkening. These findings elucidate a distinct phenotypic and nutritional divergence: intensive farming enhances overall somatic lipid retention, while natural marine environments optimize flavor-active amino acid accumulation and visual appeal, providing critical baseline markers to guide precision aquaculture. Full article

Neocinnamomum caudatum (Nees) Merr. is an underutilized woody oil plant with seeds rich in long-chain fatty acids and polyunsaturated fatty acids. Reliable quantitative real-time PCR (RT-qPCR) analysis is essential for investigating the molecular mechanisms underlying seed oil biosynthesis, but suitable reference genes have not yet been validated in this species. Here, seven candidate reference genes, namely EF-1α, ACT2, ACT11, UBQ11, TUA, F-BOX, and GAPDH, were selected from transcriptomic data and evaluated in leaves, flowers, and developing seeds of N. caudatum. Their expression stability was assessed using geNorm, NormFinder, and BestKeeper, followed by comprehensive ranking with RankAggreg. Among all tested samples (leaves, flowers and developing seeds combined), GAPDH was identified as the most stable reference gene, whereas EF-1α was the least stable. For developing seeds alone, TUA showed the highest stability, while EF-1α exhibited poor stability. In leaf and flower samples, ACT11 was the most stable gene, whereas TUA was unsuitable for normalization. The expression patterns of NcFAD2 and NcFatB, two genes involved in fatty acid biosynthesis, were used to validate the selected reference genes. Stable reference genes and the optimized multi-gene combination generated consistent expression profiles, while unstable reference genes caused evident distortion. This study provides the first systematic evaluation of reference genes for qRT-PCR analysis in N. caudatum and offers a practical foundation for future functional studies of lipid metabolism in this woody oil plant. Full article

Background/Objectives: Chemosymbiotic bivalves play a fundamental role in deep-sea cold seep and hydrothermal vent ecosystems, where essential long-chain polyunsaturated fatty acids (LC-PUFAs) are scarce. Whether these bivalves retain the capacity for endogenous PUFA synthesis remains poorly understood. Here, we investigated the PUFA biosynthetic capacity of two dominant chemosymbiotic bivalves from the Haima cold seep—the mussel Gigantidas haimaensis and the clam Archivesica marissinica. Methods: Genome and transcriptome assembly revealed three fatty acid desaturase (Fad) genes per species, which phylogenetically clustered into Δ5 (GhFads1, GhFads2; AmFads1, AmFads2) and Δ6/8 (GhFads3, AmFads3) clades, with lineage-specific duplications within the Δ5 clade. Functional assays were performed in yeast to characterize the activity of these enzymes. Results:Both Fads3 enzymes (Δ6/8 clade) convert C20:3n-6 and C20:4n-3 into C20:4n-6 and C20:5n-3, respectively, exhibiting Δ8-desaturase activity. Notably, Δ5-clade isoforms showed divergent substrate specificities: GhFads2 and AmFads1 functioned as classical Δ5-desaturases on PUFA substrates, whereas GhFads1 and AmFads2 specifically desaturated the bacterial monounsaturated fatty acid (MUFA) C18:1n-7 to produce C18:2n PUFAs. Conclusions: Together, our results reveal that cold-seep bivalves retain endogenous LC-PUFA biosynthetic capacity and have evolved duplicated Δ5-desaturases with novel regioselectivity toward bacterial MUFAs, likely representing an adaptive membrane modification for survival under extreme deep-sea conditions. Full article

This study investigated the fatty acid profile of Muli yak (Bos grunniens) milk and its relationship with compositional parameters across different parities. Milk samples from second-, third-, and fourth-parity yaks were analysed for protein, fat, vitamins, minerals, and 37 fatty acids using gas chromatography. Statistical analyses included ANOVA, correlation analysis, principal component analysis (PCA), machine learning algorithms, and molecular docking. Parity significantly affected 15 components (p < 0.05), with third-parity milk showing the highest eicosapentaenoic acid (EPA, C20:5n3) and arachidonic acid (ARA, C20:4n6) concentrations. Among 134 significant correlations, calcium-ARA and ARA-EPA exhibited strong positive associations (|r| > 0.67). PCA explained 54.2% of the variance through three principal components, differentiating samples by parity. The optimal prediction models were ARA-XGBoost, EPA-Random Forest, ALA-GAM, and LA-SVM, with calcium and protein serving as key predictors. Molecular docking revealed that EPA-FABP2 had the lowest binding energy. These parity-related shifts in functional long-chain polyunsaturated fatty acids are meaningful for the nutritional value of yak milk (e.g., omega-3/omega-6 profile) and may also influence technological properties associated with milk fat composition (e.g., oxidative stability and processing behaviour), supporting parity-oriented quality evaluation and targeted utilisation of yak milk. Full article

Obesity is a complex metabolic disorder defined by a body mass index greater than 30 kg/m², excess adipose tissue accumulation, chronic low-grade inflammation and metabolic dysfunction, leading to increased susceptibility to other chronic conditions. Evidence from both mechanistic pre-clinical studies and human clinical trial suggests a role for long-chain (LC) n-3 polyunsaturated fatty acids (PUFAs), namely eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), to modulate obesity-associated outcomes and attenuate the production of inflammatory mediators, namely adipokines from adipose tissue and myokines from skeletal muscle, that can mitigate inflammation-associated metabolic dysfunction. Therefore, this narrative review synthesizes evidence and mechanistic insights on the role(s) of n-3 PUFA in regulating obesity-associated changes in adipose tissue and skeletal muscle inflammation and immune cell trafficking and metabolic outcomes. Full article

Background: Supplementation with long-chain omega-3 polyunsaturated fatty acids (LC n-3 PUFAs), particularly eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), may mitigate exercise-induced muscle damage (EIMD) and enhance post-exercise recovery. However, the systematic reviews/meta-analyses evaluating these effects across populations and exercise models are limited and do not provide dosing recommendations. Objective: This systematic review and meta-analysis aimed to evaluate the effects of LC n-3 PUFA supplementation on key post-exercise recovery outcomes, including muscle soreness, muscle function, and muscle damage biomarkers in healthy adults. Methods: Following the PRISMA guidelines, a comprehensive search of PubMed, Scopus, and clinical trial registry databases was conducted (to January 2025). All studies that met the inclusion criteria underwent appropriate methodological quality assessments using established tools. The data were extracted for inputting into random-effects models, with effect sizes reported as Hedges’ g and 95% confidence intervals (CIs). Heterogeneity was assessed using the I² statistic. Results: Among the 2539 records, 43 studies met the inclusion criteria for the systematic review, and nine met the inclusion criteria for the meta-analysis. The effect of LC n-3 PUFA supplementation on recovery outcomes was equivocal, with significant methodological limitations noted across the literature. However, the meta-analysis of nine placebo-controlled, eccentric exercise trials demonstrated that LC n-3 PUFA supplementation significantly reduced delayed onset muscle soreness (DOMS) (Hedges’ g = −0.75; 95% CI: −1.14 to −0.36), creatine kinase (CK) (Hedges’ g = −0.40; 95% CI: −0.70 to −0.10), and muscle swelling (Hedges’ g = −0.45; 95% CI: −0.83 to −0.07), and significantly improved muscle strength (Hedges’ g = 0.45; 95% CI: 0.07 to 0.83) and range of motion (ROM) (Hedges’ g = 0.93; 95% CI: 0.33 to 1.53) at peak impairment compared with placebo. Conclusions: LC n-3 PUFA supplementation may support recovery from EIMD. However, due to the methodological limitations across the literature base it was not possible to assess effective dosing strategies. Future studies should address dose–response and duration requirements and incorporate objective assessments of omega-3 status (e.g., the Omega-3 Index [O3I] or comparable biomarkers) alongside standardized compliance measures. These approaches are necessary to determine effective dosing strategies and to test the relationship between omega-3 status and recovery outcomes. Full article

This study evaluated the effects of dietary supplementation with goji berries (Lycium barbarum) on the nutritional profile, oxidative stability, and shelf life of rabbit meat. Thirty-two rabbits were assigned to two dietary treatments: a control diet (CN) and the same diet supplemented with 3% dried goji berries (GJ). Proximate composition and fatty acid profile of the Longissimus thoracis et lumborum muscle were determined at dissection, whereas physical, microbiological, and biochemical parameters were evaluated during refrigerated storage (4 °C; 1, 4, and 10 days) and frozen storage (−20 °C; 60 and 120 days). Dietary supplementation significantly modified the lipid profile of the meat, reducing saturated fatty acids and increasing long-chain n-3 and n-6 polyunsaturated fatty acids. During refrigerated storage, lipid peroxidation increased in both groups; however, meat from the GJ group showed significantly lower TBARS values after 10 days (0.22 vs. 0.33 mg MDA/kg; p < 0.001), indicating improved oxidative stability. Lower accumulation of total volatile basic nitrogen (TVB-N), reduced formation of biogenic amines, and slower growth of spoilage-related microbial populations, particularly Pseudomonas spp., were also observed in GJ samples. Overall, the GJ diet improved fatty acid composition and delayed degradative processes during storage, suggesting its potential as a functional feed ingredient to enhance rabbit meat quality and shelf life. Full article

Sjögren’s disease (SjD) is a chronic autoimmune disorder characterized by progressive dysfunction of the exocrine glands, driven primarily by aberrant T- and B-cell activation. Current therapeutic strategies remain largely symptomatic and are frequently limited by off-target effects and long-term toxicity, underscoring an urgent need for safer, mechanism-based adjunctive approaches. In recent years, nutritional interventions and medicinal herbs have emerged as promising complementary strategies, owing to their capacity to modulate immune–metabolic pathways and restore immune homeostasis. Nutrients such as n-3 polyunsaturated fatty acids (PUFAs) and short-chain fatty acids (SCFAs) exert well-documented anti-inflammatory effects and influence immune cell differentiation via immunometabolic reprogramming. Concurrently, bioactive constituents derived from medicinal herbs offer multi-target regulation of inflammatory signaling and lymphocyte function. This review synthesizes current advances in the immunomodulatory roles of dietary components and edible herbs in the context of SjD, focusing on their mechanistic convergence on T-cell subsets, B-cell responses, and the gut–immune axis. By integrating traditional knowledge with contemporary immunological insights, this article aims to provide a conceptual framework for the rational integration of nutritional and herbal strategies into the clinical management of SjD. Full article

Thraustochytrids are promising alternatives for the production of docosahexaenoic acid (DHA; C22:6 n-3), a long-chain polyunsaturated fatty acid with health benefits. For practical application of this oleaginous microorganism, an efficient cultivation method to enhance DHA production is required, which relies on several factors that support cell growth, lipid accumulation, and lipid turnover. In this study, the robust submerged fermentation of an acid- and high-temperature-tolerant strain of Aurantiochytrium limacinum was investigated. Under controlled temperature and acidic conditions (pH 4.5 and 30 °C), glucose and peptone were the best carbon and nitrogen sources for enhancing biomass and DHA production, respectively, with a glucose concentration of 60 g/L and a C/N ratio of 24 being optimal for DHA production. Applying an aeration rate of 2 vvm and an agitation speed of 300 rpm using a combination of a ring sparger and pitch-blade impeller in a stirred-tank bioreactor improved DHA production using intermittent fed-batch fermentation. The highest DHA titer was obtained at 3.01 g/L, and the DHA content in biomass was 10.69% (w/w) after intermittent feeding of cassava starch hydrolysate as the substrate. Full article

Background: n-3 Docosapentaenoic acid (DPA; 22:5 n-3) is increasingly viewed as a distinct long-chain omega-3 fatty acid with biological activities that are not fully captured by eicosapentaenoic acid (EPA) or docosahexaenoic acid (DHA). However, progress remains limited by restricted access to high-purity DPA: most commercial sources contain DPA as a minor component, and published isolation strategies often yield only enriched mixtures or require multi-step workflows that are difficult to scale in standard laboratories. Objectives: We aimed to establish a robust, laboratory-accessible purification workflow to obtain DPA ethyl ester at high purity while preserving oxidative quality. Methods: Candidate lipid sources were screened to select an optimal DPA-containing feedstock. Oils were stabilized with antioxidants and pre-fractionated by cold crystallization (−20 °C) to reduce saturated lipids and oxidation by-products. Preparative separation used a stacked C18 flash system (15 μm + 45 μm in series) operated isocratically (methanol/water 92:8, v/v) at 120 mL/min. Fractions were analyzed by GC and iteratively reinjected to progressively enrich the DPA window. Solvent was recovered by distillation and reused. Results: Omegavie^® 4020EE (5.4% n-3 DPA) was identified as the best starting material. Pretreatment eliminated detectable TBARS-derived malondialdehyde. The isocratic purification-loop strategy produced tens of grams of DPA ethyl ester at >98% purity (GC–FID) defined as n-3 DPA area% of total identified fatty acid methyl esters by GC–FID, with per-cycle DPA recovery of 91–95%, overall recovery of 76% from the starting DPA content, and >90% solvent recycling. The workflow is scalable at the gram-to-tens-of-grams level for research laboratories, although solvent burden and column maintenance remain practical constraints for larger-scale implementation. Identity and purity were confirmed by GC–MS and ^1H NMR, and oxidation indices remained low (peroxide value < 0.2 meq/kg; p-anisidine < 3). Conclusions: This scalable, solvent-conscious protocol enables reliable access to high-purity DPA and should be adaptable to other low-abundance polyunsaturated fatty acids. Full article