Search

Background: Pro-inflammatory processes triggered by the accumulation of extracellular amyloid beta (Aβ) peptides are a well-described pathology in Alzheimer's disease (AD). Activated astrocytes surrounding Aβ plaques contribute to inflammation by secreting proinflammatory factors. While astrocytes may phagocytize Aβ and contribute to Aβ clearance, reactive astrocytes may also increase Aβ production. Therefore, identifying factors that can attenuate astrocyte activation and neuroinflammation and how these factors influence pro-inflammatory pathways is important for developing therapeutic and preventive strategies in AD. Here, we identify the platelet-activating factor receptor (PTAFR) pathway as a key mediator of astrocyte activation. Intriguingly, several polar lipids (PLs) have exhibited anti-inflammatory protective properties outside the central nervous system through their inhibitory effect on the PTAFR pathway. Thus, we additionally investigated whether different PLs also exert inhibitory effects on the PAF pathway in astrocytes and whether their presence influences astrocytic pro-inflammatory signaling and known AD pathologies in vitro. Methods: PLs from salmon and yogurt were extracted using novel food-grade techniques and their fatty acid profile was determined using LC/MS. The effect of PLs on parameters such as astrocyte activation and generation of oxygen species (ROS) was assessed. Additionally, effects of the secretome of astrocytes treated with these polar lipids on aged neurons was measured. Results: We show that PLs obtained from salmon and yogurt lower astrocyte activation, the generation of reactive oxygen species (ROS), and extracellular Aβ accumulation. Cell health of neurons exposed to the secretome of astrocytes treated with salmon-derived PLs and Aβ was less affected than those treated with astrocytes exposed to Aβ only. Conclusion: Our results highlight a novel underlying mechanism, why consuming PL-rich foods such as fish and dairy may reduce the risk of developing dementia and associated disorders. [ABSTRACT FROM AUTHOR]

Process parameters were optimised using Taguchi orthogonal array design for extraction of phospholipids (PLs) from ghee residue (GR) with pulsed electric field (PEF) assistance. For higher PL yield and antioxidant activity, process voltage and time were observed to be significant factors. Optimised conditions were determined as 60 kV/cm voltage at 7.5 (v/w) solvent (water)‐to‐solid ratio for 5 min. Physical disruption of GR matrix due to PEF treatment was established through scanning electron micrographs. Lipidomic profile of the extract ascertained through liquid chromatography‐mass spectrophotometry (LC–MS) revealed multiple species of phosphatidylcholine, phosphatidylethanolamine, phosphatidylinositol and phosphatidylserine in the resultant extract. [ABSTRACT FROM AUTHOR]

Most lipids in our diet come under the form of triacylglycerols that are often redispersed and stabilized by surfactants in processed foods. In plant however, lipid assemblies constitute interesting sources of natural bioactive and functional ingredients. In most photosynthetic sources, polar lipids rich in ω3 fatty acids are concentrated. The objective of this review is to summarize all the knowledge about the physico-chemical composition, digestive behavior and oxidative stability of plant polar lipid assemblies to emphasize their potential as functional ingredients in human diet and their potentialities to substitute artificial surfactants/antioxidants. The specific composition of plant membrane assemblies is detailed, including plasma membranes, oil bodies, and chloroplast; emphasizing its concentration in phospholipids, galactolipids, peculiar proteins, and phenolic compounds. These molecular species are hydrolyzed by specific digestive enzymes in the human gastrointestinal tract and reduced the hydrolysis of triacylglycerols and their subsequent absorption. Galactolipids specifically can activate ileal break and intrinsically present an antioxidant (AO) activity and metal chelating activity. In addition, their natural association with phenolic compounds and their physical state (Lα state of digalactosyldiacylglycerols) in membrane assemblies can enhance their stability to oxidation. All these elements make plant membrane molecules and assemblies very promising components with a wide range of potential applications to vectorize ω3 polyunsaturated fatty acids, and equilibrate human diet. [ABSTRACT FROM AUTHOR]

Marine macroalgae are emerging as sustainable and healthy food, and a source of lipids with nutritional and bioactive properties. Nonetheless, the lipidome of macroalgae is little explored compared to other photosynthetic organisms. Most of the literature is devoted to the analysis of fatty acid (FA) from macroalgae, because of they are a source of long‐chain omega‐3 and omega‐6 polyunsaturated FA, which can be used as an alternative to fish oil. However, FA occurs mostly esterified in other lipids, such as polar lipids, that still overlooked. The data published on the study of polar lipids (phospholipids, glycolipids, betaine lipids) pinpoint their remarkable characteristics and bioactive properties which mainly remain unexplored. The lipidome of macroalgae seems to be species‐specific, while some lipid classes appear to be characteristic of phyla. Lipidome plasticity of macroalgae is verified to change under abiotic and biotic factors which may modulate the functionality and add‐value of the biomass. This biochemical plasticity represents an advantage to obtain ingredients for target applications and niche of markets. This review provides an overview on macroalgae lipidome characterization, addressing analysis workflow based on liquid chromatography coupled to mass spectrometry, and discussing the bioactive properties and biotechnological applications of macroalga lipids. Practical Applications: The current state of the art on marine macroalgae lipidomics is reviewed, including the lipid characterization using modern liquid chromatography‐mass spectrometry, the distribution of polar lipids by macroalgae species and phylum, their bioactive properties, and potential biotechnological applications. In a time of increasing awareness of sustainably produced marine resources, the lipids from macroalgae are still underexplored. This review provides information for smart valorization of macroalgae as source of add‐value lipids contributing to the development of blue bioeconomy. [ABSTRACT FROM AUTHOR]

One of the more surprising occurrences of bulk nanobubbles is in the sap inside the vascular transport system of flowering plants, the xylem. In plants, nanobubbles are subjected to negative pressure in the water and to large pressure fluctuations, sometimes encompassing pressure changes of several MPa over the course of a single day, as well as wide temperature fluctuations. Here, we review the evidence for nanobubbles in plants and for polar lipids that coat them, allowing nanobubbles to persist in this dynamic environment. The review addresses how the dynamic surface tension of polar lipid monolayers allows nanobubbles to avoid dissolution or unstable expansion under negative liquid pressure. In addition, we discuss theoretical considerations about the formation of lipid-coated nanobubbles in plants from gas-filled spaces in the xylem and the role of mesoporous fibrous pit membranes between xylem conduits in creating the bubbles, driven by the pressure gradient between the gas and liquid phase. We discuss the role of surface charges in preventing nanobubble coalescence, and conclude by addressing a number of open questions about nanobubbles in plants. [ABSTRACT FROM AUTHOR]

Jaw malformations imply an important problem during the commercial production of Seriola lalandi larvae and juvenile fish in Chile and New Zealand. Since the rate of malformations in other fish species has been associated with the content of long-chain PUFA (LC-PUFA) in neutral lipids of the diet, the relationship between body LC-PUFA and the rate of malformations, together with a transcriptomic analysis of genes related to the metabolism and transport of lipids in commercially produced S. lalandi larvae have been investigated in the present work. A total of 10 batches of S. lalandi larvae were obtained and cultured at about 22 °C following the protocols of a Chilean commercial hatchery during the spawning season. There were three larval batches that were collected in August (austral winter), three batches that were obtained in October (spring), and finally four spawning events that were obtained in December-January (spring-summer). The rate and type of jaw malformations, the profile of long-chain PUFA (LC-PUFA) of total lipids during larval culture, and the distribution of LC-PUFA were analyzed. Additionally, a transcriptome analysis related to lipid metabolism in 40-day-old larvae was performed. As a result, a decrease in the rate of malformations was recorded from August to December. DHA showed a steep decrease between days 1 and 10 of culture, probably due to the consumption of yolk sac lipids, but a higher proportional change was noted in larvae that hatched during August. The DHA content in polar lipids (PL) and neutral lipids (NL) of 40-day-old larvae increased from August to December, so that the abundance of DHA was higher in PL in larvae that hatched in December, but it was higher in NL in those larvae that hatched in October. In conclusion, the rate of jaw malformations was associated with the rapid decline in DHA during early larval life and the highest abundance of DHA in neutral lipids at the end of the larval life. [ABSTRACT FROM AUTHOR]

Fourteen wild (W) and cultivated (C) seed samples from nine Onosma species were collected in various climate zones and were analyzed for contents of neutral lipids (NL) and polyunsaturated fatty acids (PUFAs). The species O. tanaitica (C and W), O. rigidum (W), and O. simplicissima (W) had the richest contents of NL (from 17.5 to 20.5%) and PUFAs (from 74 to 80%). The compositions of NL, polar lipids, and several lipophilic constituents of seeds of wild O. simplicissima growing in the Republic of Bashkortostan were determined. Six NL classes and the contents and compositions of tocopherols (18.2 mg/100 g of seeds) and sterols (77.5 mg/100 g) were identified in seeds of the species. The main constituent of the tocopherols was γ-tocopherol; of the sterols, ∆-5-avenasterol. [ABSTRACT FROM AUTHOR]

Sphingomyelins, the most abundant sphingolipids in most mammalian cells, appear to be among the most represented polar lipids in breast milk. Despite the variability of the data reported in the literature, human milk sphingomyelins are qualitatively unique and their quantities are five times higher than in most formula milk. The structural and functional role within the milk fat globule membranes, the involvement in neonatal neurological maturation both in neuro-typical development and in some pathological circumstances, together with the possible contribution in the intestinal development of newborns, are certainly among the main characteristics that have fueled the curiosity of the scientific world. Metabolomics studies, providing a unique metabolic fingerprint, allow an in-depth analysis of the role of these molecules in the extreme variability and uniqueness of breast milk. In the perspective of preventive medicine, at the base of which there is certainly personalized nutrition, it is possible, in the presence of particular conditions, such as neonatal growth retardation or in preterm infants, to consider supplementation of some target nutrients, such as certain sphingomyelins. Nevertheless, further studies are needed to more accurately assess whether and how the type and quantity of sphingomyelins present in breast milk could affect the metabolic health of newborns. HIGHLIGHTS Breast milk is the golden standard for infants’ nutrition Sphingomyelins are the most represented polar lipids in breast milk These molecules are involved in both intestinal and neural developments of newborns Metabolomics is a very useful tool to investigate their precise role Further studies are needed to provide eventual nutritional treatment. [ABSTRACT FROM AUTHOR]

Sphingomyelins, the most abundant sphingolipids in most mammalian cells, appear to be among the most represented polar lipids in breast milk. Despite the variability of the data reported in the literature, human milk sphingomyelins are qualitatively unique and their quantities are five times higher than in most formula milk. The structural and functional role within the milk fat globule membranes, the involvement in neonatal neurological maturation both in neuro-typical development and in some pathological circumstances, together with the possible contribution in the intestinal development of newborns, are certainly among the main characteristics that have fueled the curiosity of the scientific world. Metabolomics studies, providing a unique metabolic fingerprint, allow an in-depth analysis of the role of these molecules in the extreme variability and uniqueness of breast milk. In the perspective of preventive medicine, at the base of which there is certainly personalized nutrition, it is possible, in the presence of particular conditions, such as neonatal growth retardation or in preterm infants, to consider supplementation of some target nutrients, such as certain sphingomyelins. Nevertheless, further studies are needed to more accurately assess whether and how the type and quantity of sphingomyelins present in breast milk could affect the metabolic health of newborns. [ABSTRACT FROM AUTHOR]

Chlorococcum amblystomatis is a novel microalga with a high content of omega-3 fatty acids (FAs), with applications for food, feed, nutraceuticals, and biotechnology. These applications require the use of food-grade green solvents such as ethanol (EtOH) for lipid extraction, which can be associated with lower lipid recovery yields if not assisted with mechanical means. Ultrasonication can increase the recovery of lipids and omega-3 FAs, however, the impact on polar lipids remains poorly understood. In this study, we propose a comparative lipidomic analysis through liquid-chromatography mass spectrometry (LC–MS) of extracts obtained with EtOH combined with ultrasound-assisted extraction (UAE) and conventional extraction with dichloromethane:methanol (DCM) or EtOH. Extraction with UAE improved the recovery yield of EtOH alone from 2.3 ± 0.3 to 14.6 ± 0.6%, which is comparable to lipid recovery from DCM (16.7 ± 0.8%). The fatty acid profile of UAE extracts showed no differences in comparison with DCM. Lipidomic LC–MS/MS analysis showed that UAE allowed lipid extracts rich in polar lipids containing omega-3 PUFAs with lipid yield and lipid profile similar to DCM to be obtained. Taken together these results demonstrate the effectiveness of UAE in obtaining extracts rich in omega-3 glycolipids and phospholipids from C. amblystomatis for different biotechnological applications. [ABSTRACT FROM AUTHOR]

The growing resistance from pathogens against antibiotics has increased the research for new compounds and strategies with antibacterial potential. Lipids from algae are emerging as natural and potent bioactive molecules with interesting results regarding the inactivation of bacteria, viruses, and fungi. The combination of algae lipids with innovative strategies, such as antibacterial photodynamic therapy (aPDT) can enhance their antimicrobial potential. In this work, we aimed to evaluate the antibacterial potential in aPDT of total lipid extracts and polar lipid fractions from the green macroalga, Codium tomentosum , and the green microalga, Chlorella vulgaris on a Gram-positive bacteria Staphylococcus aureus. Total lipid extracts and polar lipid fractions were characterized by LC-MS. The results revealed that the total extracts of algae promote S. aureus inhibition after light irradiation, with a decrease of ca. 6 log 10 (CFU/mL) after 15 min of treatment with both extracts of algae. The polar lipid fractions, composed by phospholipids, glycolipids and betaine lipids, from C. tomentosum and C. vulgaris also revealed antibacterial potential in combination with aPDT, but a decrease of ca. 6 log 10 (CFU/mL) was reached at 60 min of treatment, later than with the total extracts. These results unveil algae lipids as antibacterial compounds in combination with aPDT displaying an alternative from natural origin to tackle pathogen resistance. • Algae total extracts are effective photosensitizers when used with aPDT. • Lipids from C. tomentosum and C. vulgaris reduce the viability of S. aureus in aPDT. • Algae polar lipids are effective photosensitizers when used with aPDT. • Algae polar lipids combined with aPDT can enhance their antimicrobial potential. [ABSTRACT FROM AUTHOR]

The stability to oxidation during long-term storage of neutral lipids of common borage (Borago officinalis L.) seeds was studied. The organoleptic indices and contents of pigments and fatty acids remained almost unchanged for two years. The antioxidant activity of neutral lipids (NL) and polar lipids (PL) of B. officinalis seeds was determined using a model of radical chain oxidation of methyl oleate. Both NL and PL were found to contain antioxidants suppressing the oxidation of methyl oleate. The antioxidant activity and antioxidant content in NL were greater than those in PL of B. officinalis seeds. Long-term storage of B. officinalis seed oil was possible because of the presence of the antioxidant a-tocopherol. [ABSTRACT FROM AUTHOR]

For fish oil-free aquafeed development, a photoautotrophic microalga Tisochrysis lutea is believed to be the candidate source of n-3 highly unsaturated fatty acid (n-3 HUFA) because of its docosahexaenoic acid (DHA) biosynthesis. While DHA contents of T. lutea vary during the cultivation periods depending on algal growth phase, little is mentioned about how this dependence should be taken into consideration when evaluating the suitability of microalgae as an alternative to fish oil-formulated diets. Here, we compared nutritionally maximized cells of deceleration growth phase T. lutea and fish oils-formulated product (n-3 HUFA-enriched Chlorella) as a rotifer enrichment diet for enhancement in Japanese flounder Paralichthys olivaceus larviculture. T. lutea had higher concentrations of DHA in the polar lipids than those for enriched Chlorella. Such higher concentrations of T. lutea were estimated only in the deceleration growth phase (not in the logarithmic growth or stationary phase). When deceleration growth phase T. lutea were fed to Brachionus plicatilis rotifers previously cultured on unenriched Chlorella, the DHA of the rotifers was boosted up to the level in those fed with enriched Chlorella. Furthermore, use of T. lutea-fed rotifers for initial feeding of fish larvae enhanced the growth, survival, n-3 HUFA levels, and final juvenile productivity of the larvae as much as feeding the larvae with enriched Chlorella-fed rotifers. We propose that T. lutea in the deceleration growth phase are efficacious, fish oil-free sources of n-3 HUFA for marine fish larviculture. [ABSTRACT FROM AUTHOR]

The marine microalga Tisochrysis lutea is a potential and sustainable source of bioactive compounds such as carotenoids and omega-3 fatty acids. In the present work, the extraction of fucoxanthin and docosahexaenoic acid (DHA), the most abundant omega-3 fatty acid which constitutes polar lipids particularly in the brain, was studied using advanced extraction techniques with green and bio-based solvents compared to traditional extraction techniques with hazardous organic solvents. The experimental design to maximize the lipid extraction yield by ultrasound-assisted extraction (UAE) was developed, choosing as experimental factors the percentage of solvent (0, 50 and 100% of 2-methyl-tetrahydrofuran or 2-methyloxolane (2-me-THF) in ethanol), the extraction time (20, 30 and 40 min) and temperature (40, 50 and 60 ºC). The highest lipid extraction yields were obtained using ethanol as solvent. Nevertheless, the most interesting extracts based on their chemical composition were obtained when the presence of 2-me-THF in the extraction mixture was greater than that of ethanol. Through analytical techniques such as HPLC-ELSD/DAD and GC-MS as well as spectrophotometric techniques, the contents of polar lipids, fatty acids, total carotenoids and fucoxanthin were quantified. In addition, the antioxidant capacity of different selected extracts was studied, being once again the most interesting those extracted with different amounts of 2-me-THF due to its selectivity and enriched composition in high-added value bioactives, mainly fucoxanthin and DHA. Therefore, it is shown the importance of choosing an advanced extraction technique together with the use of green solvents not only to develop procedures that are in agreement with Green Chemistry but also to preserve its bioactivity. [ABSTRACT FROM AUTHOR]

Marine microalgae often live in a fluctuating environment including a decrease in salinity caused by global warming induced sea ice melting and freshwater inflows. Under conditions of fluctuating salinity, microalgae have evolved a variety of survival mechanisms such as lipid accumulation and remodeling. The purpose of this study was to investigated the membrane lipid remodeling of the marine green microalga Dunaliella tertiolecta as a short-term acclimation mechanism in response to hyposalinity (20 and 3 PSU) with respect to growth at optimal salinity (38 PSU). We identified 34 lipid species belonging to seven polar lipid classes. Dunaliella tertiolecta accumulates cell lipids and remodels polar lipid classes and their fatty acids composition as response to hypoosmotic stress at 3 PSU. We found that the unsaturation of most polar lipids decreases overall, indicating decreased membrane fluidity and altered permeability, whereas shortening the length of fatty acids of polar lipids is not one of the strategies of D. tertiolecta to cope with the decrease in salinity. Increase in relative content (%) and unsaturation of monogalactosyldiacylglycerols (MGDG) and decrease in relative content (%) and unsaturation of phosphatidylglycerols (PG), suggesting changes in photosynthetic membranes of thylakoids at 20 and 3 PSU. At a very low salinity of 3 PSU, the relative content (%) of phosphatidylinositols (PI) increases, suggesting increased lipid trafficking and signaling in the cells. These changes are statistically significant and we hypothesize that D. tertiolecta is genetically adapted to withstand large salinity fluctuations through polar lipid composition. [ABSTRACT FROM AUTHOR]

Very-long-chain fatty acids (VLCFA) are involved in a number of important plant physiological functions. Disorders in the expression of genes involved in the synthesis of VLCFA lead to a number of phenotypic consequences, ranging from growth retardation to the death of embryos. The elongation of VLCFA in the endoplasmic reticulum (ER) is carried out by multiple elongase complexes with different substrate specificities and adapted to the synthesis of a number of products required for a number of metabolic pathways. The information about the enzymes involved in the synthesis of VLCFA with more than 26 atoms of Carbon is rather poor. Recently, genes encoding enzymes involved in the synthesis of both regular-length fatty acids and VLCFA have been discovered and investigated. Polyunsaturated VLCFA in plants are formed mainly by 20:1 elongation into new monounsaturated acids, which are then imported into chloroplasts, where they are further desaturated. The formation of saturated VLCFA and their further transformation into a number of aliphatic compounds included in cuticular waxes and suberin require the coordinated activity of a large number of different enzymes. [ABSTRACT FROM AUTHOR]

• Extended food use of oats calls for knowledge on compositions and storage behavior. • Lipids, volatiles and tocopherols varied between 20 pure oat cultivar batches. • Nine-month storage of flour revealed differences in oxidative stability. • Minor correlations between lipids, tocols and volatile oxidation compounds detected. Recent data showing the compositional variation and storage behavior among different oat batches for the purpose of food remains limited. Lipids of twenty oat flour samples of pure cultivars grown in Finland during 2019 were extracted and fractionated into neutral and polar-rich lipids. Flour was stored for nine months, and profiles of volatiles and tocols were analyzed to reveal oxidative stability. The lipid content was 5.9–8.9 g per 100 g of flour [DW] and consisted of 78.7 ± 2.5 % neutral and 21.3 ± 2.5 % polar lipids. Palmitic (16 %), oleic (36 %), and linoleic (39 %) acids were the most abundant fatty acids. Neutral lipids had more oleic and less linoleic and palmitic acids than polar lipids. The fresh samples correlated with tocols, pentanal, 2-pentylfuran, 2-heptanone, nonanal, 2-butanone, and heptanal, while stored samples were associated with 3-octen-2-one, 2-octenal, hexanal, and octanal. Lipid composition and oxidative stability are essential factors for selecting oat batches for food applications. [ABSTRACT FROM AUTHOR]

This study characterizes milk triacylglycerol (TAG) and polar lipid (PL) fractions from cows and goats fed various lipid supplements modulating milk fat content. Twelve Holstein cows and 12 Alpine goats, at 86 ± 24.9 and 61 ± 1.8 days in milk, respectively, are allocated to one of 4 groups to receive diets supplemented with either corn oil [5% dry matter intake (DMI)] plus wheat starch (COS), marine algae powder (MAP; 1.5% DMI) or hydrogenated palm oil (HPO; 3% DMI), or a no‐added‐lipid control diet (CTL), according to a 4 × 4 Latin square design with 28 d experimental periods. Milk TAG and PL contents are determined by liquid chromatography‐mass spectrometry (LC‐MS). Multivariate analysis and ANOVA demonstrate major between‐species differences in diet effects. In cows, COS specifically increases TAG 54:3 and 54:4 associated with milk fat depression (MFD), and increases the sum of phosphatidylcholines (PC) and phosphatidylinositols (PI). In addition to causing a MFD, MAP diet increases long‐chain polyunsaturated TAG in both species, with higher magnitude in cows than in goats, and decreases the sum of PI in goats. HPO increases TAG 52:1 and the sum of PI in cows, but not in goats. Practical applications: Feed strategies can quickly and efficiently modulate the ruminant milk fat production and composition to improve nutritional quality for consumers. Certain starch‐rich diets supplemented with polyunsaturated fatty acids (PUFA)‐rich vegetable oils and diets supplemented with marine products (long‐chain PUFA) reduce milk fat secretion and modify the milk fatty acid (FA) profile in cows, but not—or less so—in goats. Advanced analysis of both the TAG and PL fractions of milk fat is required to unravel these differences in lipid metabolism between cows and goats fed various lipid‐supplemented diets. This study brings new insight on using nutritional strategies to control milk lipid composition according to ruminant species. [ABSTRACT FROM AUTHOR]

Alternative ways for increased appetite control are today widely sought for due to the growing global health issues connected to obesity. In in vivo studies, oat has been proven an attractive candidate for inducing satiety. Oat is rich in polar lipids, of which the galactolipids are especially interesting, and a hypothesis is that these lipids play an important role for the ileal brake mechanism. In this study, the aim is to investigate the role of polar oat lipids on pancreatic lipolysis rate, using a pH‐stat based in vitro digestion model of the duodenum. Lipolysis of oat oil, a mix of oat oil/rapeseed oil (RSO), as well as a liquid oat base (OB) simulating an oat drink with different polar lipid content are investigated, and compared with RSO as control. Increasing the polar lipid content of the product digested leads to a significantly decreased lipolysis rate, and this effect is even observed when mixing RSO with a low amount of oat oil (10%). The results support the hypothesis that polar lipids can delay lipolysis also in a complex, natural system like the liquid OB, and even a minor amount of oat lipids can have large effect on lipolysis rates. Practical applications: The number of studies connecting galactolipids with a decreasing effect on duodenal lipolysis is growing; however, the mechanism behind this phenomenon is still not clarified. Here, the same effect is seen in a complex, natural food system. These findings open up for interesting future food products, where inclusion of oat oil, even at low concentrations, can have a prolonging effect on satiety. Oat for human consumption is an increasing market, thanks to the positive health benefits oat has been connected to, in combination with the current trend toward climate‐friendly plant‐based options for meat and dairy products. It is believed that oat oil can be attractive as an ingredient in various food products, for example, protein bars and spreads. More studies are needed to confirm the results in vivo. However, a great potential is seen for the use of oat oil to enhance appetite control. [ABSTRACT FROM AUTHOR]

Adaptive laboratory evolution is a powerful tool for microorganism improvement likely to produce enhanced microalgae better tailored to their industrial uses. In this work, 12 wild-type strains of Tisochrysis lutea were co-cultivated under increasing thermal stress for 6 months. Indeed, temperature was oscillating daily between a high and a low temperature, with increasing amplitude along the experiment. The goal was to enhance the polyunsaturated fatty acid content of the polar lipids. Samples were taken throughout the evolution experiment and cultivated in standardized conditions to analyze the evolution of the lipid profile. Genomic analysis of the final population shows that two strains survived. The lipid content doubled, impacting all lipid classes. The fatty acid analyses show a decrease in SFAs correlated with an increase in monounsaturated fatty acids (MUFAs), while changes in polyunsaturated fatty acid (PUFAs) vary between both photobioreactors. Hence, the proportion of C18-MUFAs (18:1 n-9) and most C18-PUFAs (18:2 n-6, 18:3 n-3, and 18:4 n-3) increased, suggesting their potential role in adjusting membrane fluidity to temperature shifts. Of particular interest, DHA in polar lipids tripled in the final population while the growth rate was not affected. Key points: • Adaptive laboratory evolution on a mix of 12 T. lutea strains led to survival of 2 • Thermal stress impacted cell size, total lipid cell content, and all lipid classes • DHA cell content partitioned to polar lipids tripled throughout the experiment [ABSTRACT FROM AUTHOR]

In larviculture of marine finfish, Tisochrysis lutea cultured cells have a potential to be a sustainable enrichment diet for rotifers due to its de novo synthesis of docosahexaenoic acid (DHA). To improve its effectiveness in rotifer enrichment for later larviculture, we determined which growth phase of T. lutea can enhance DHA in polar lipids (PLs) in Brachionus plicatilis sp. complex rotifers without reducing their vigor. Tisochrysis lutea was harvested at logarithmic growth phase, deceleration growth phase, and stationary phase. The ambient concentrations of phosphorus (P) and nitrogen (N), and fatty acid composition of microalgae were measured. P was limited between logarithmic and deceleration growth phases, followed by N starvation in stationary phase. Total lipid DHA was lowest in logarithmic growth phase, whereas DHA levels increased in deceleration growth phase and maintained at high levels even in stationary phase. PL-DHA also increased during deceleration growth phase, although its abundance dropped during stationary phase. In a rotifer enrichment trial, T. lutea harvested in each phase were fed to B. plicatilis sp. complex rotifers for 12 h. The highest PL-DHA value for cells in deceleration growth phase reflected the concentrations of the rotifers. No significant differences were found in rotifer growth rate and egg ratio. Rotifers fed cells in deceleration growth phase exhibited higher swimming speeds than those fed the other cells, potentially linking to increased larval capture success. Therefore, we recommend the deceleration growth phase as an optimal timing for T. lutea harvest for the effective enrichment of B. plicatilis sp. complex rotifers. [ABSTRACT FROM AUTHOR]

The objective of this study was to develop an integrative approach in ecotoxicology (from biomarkers to population genetics) to assess the ecological status of fish populations. Flounders (Platichthys flesus) collected after the spawning season in the heavily polluted Seine estuary were compared with the moderately polluted Bay of Douarnenez. The muscle energetic reserves were highly depleted in Seine vs. Douarnenez fish. The Seine fish displaying a reduced capacity to manage the oxidative stress and a higher energetic metabolism. An increase in the content of muscle membrane phospholipids (sphingomyelin, phosphatidylserine, free sterols) was detected in the Seine vs. Douarnenez fish. The data integration allowed to hypothesize relationships between membrane phospholipids, xenobiotic metabolism, bioenergetics, and antioxidant defence. The genetic diversity considering neutral markers was maintained in the heavily polluted Seine population compared with the Douarnenez population. Finally, we suggest that the high physiological cost of tolerance to toxicants in the Seine flounder population could compromise its capacity to respond in the future to an additional stressor like warming waters in shallow depth. Thus, this population could be submitted to an ecological risk. [ABSTRACT FROM AUTHOR]

Polar lipids, especially glycerophospholipids, constitute the main components of cell membranes and are precursors of signaling molecules in many cellular and physiological processes. For this reason, the development of methods with high capability for detection of polar lipids in biological samples is required. In this research, the objective was to develop a method for comprehensive qualitative/quantitative determination of polar lipids in plasma by a combination of acquisition methods with a triple quadrupole mass analyzer. The strategy was optimized in two steps: (a) a first step for detection of lipids by monitoring selective fragmentation patterns representative of each lipid family and (b) a second step for confirmation of lipid species by detection and identification of product ions associated with the conjugated fatty acids. The acquisition list was divided into two multiple reaction monitoring (MRM) methods to ensure the detection of all transitions with suited instrumental sensitivity according to chromatographic retention time and relative abundance in plasma. The combination of the two MRM methods allowed the detection of 398 polar lipids in plasma in 64 min. Precision, estimated as within-day variability, was below 6.8% for all determined lipid families, while between-day variability was below 24.0%. This strategy has been applied to a cohort formed by 384 individuals in order to obtain a qualitative and quantitative distribution of polar lipids in human plasma. The most concentrated lipid families in relative terms were lysophospholipids, plasmalogens, and phosphatydilcholines, with mean relative concentration of 58.0, 17.1, and 8.3%, respectively. Then, sphingomyelins and phosphatidylethanolamines reported a relative concentration of 2.0%, followed by phosphatidylserines, with 1.1%. [ABSTRACT FROM AUTHOR]

Background: Polar lipids from wheat (Triticum vulgare/aestivum) extract oil (WEO) are known to improve skin hydration. Aims: These studies aimed to assess WEO benefits on the skin appearance of middle‐aged women. Methods: A double‐blind, randomized, placebo‐controlled clinical study was carried out on 64 healthy women, aged from 45 to 60 years, to investigate antiaging effects and benefits for the skin. The study lasted 20 weeks including 12 weeks of oral supplementation with WEO or placebo and 8 weeks of follow‐up. Wrinkles in the "crow's‐feet" area were evaluated by the Lemperle score. Skin hydration was measured using a corneometer, while roughness and radiance were determined by clinical scoring. Collagen content was quantified in human skin explants exposed to ultraviolet (UV) irradiations and treated with WEO or vehicle control. Results: Compared to the placebo group, the Lemperle score was significantly reduced in the WEO group between W0 and W8 to reach a clinically significant 1 grade at W12. Facial hydration was significantly improved in the WEO group from W0 to W12, whereas leg hydration was significantly increased after 4 weeks and lasted throughout the supplementation period. Skin roughness and radiance were also significantly improved from W0 to W8 in the WEO group compared to placebo group. A higher collagen content was measured in the UV‐irradiated skin explants treated with WEO compared to the untreated ones. Conclusion: These results confirmed the moisturizing effect of WEO and, for the first time, revealed its potential antiaging properties. [ABSTRACT FROM AUTHOR]

• Advantages of sheep milk lipid fraction. • Minor nitrogenous compounds of sheep milk with nutritional/biological value. • Nutritional potential of sheep milk products and by-products. The purpose of the present review is to highlight specific features of the components of sheep milk and dairy products with nutritional and biological significance. Fatty acid profile, milk fat globule size, high CLA, sphingomyelin and fat-soluble vitamins contents are more advantageous in nutritional terms, compared to cow milk. Apart from the high protein content and the several related types of biofunctionality, the non-protein fraction of sheep milk is also significant. In this respect, findings on bioactive peptides, proteose-peptone fraction, nucleoside/nucleotide and polyamine contents are reviewed. Finally, minerals and minor compounds such as oligosaccharides and water-soluble vitamins are presented. It is concluded that sheep milk and dairy products are excellent food matrices, while a great part of beneficial sheep milk components is transferred to by-products. [ABSTRACT FROM AUTHOR]

Within the chemical transformations that vegetable oils undergo, oxidative reactions are one of the most widely studied. During the process of oxidation oils react with oxygen in their different forms to produce a large variety of chemical species that alter their chemical and physical properties. This work is the second of a series of two in which the action of ozone on different sunflower oils was investigated. Ozone reacts with double bonds of unsaturated fatty acids which produce different peroxidated species. The presence of altered triacylglycerol (TAG) increases the polarity of the vegetable oils and induces changes in their physical properties. Moreover, peroxygenation alters the aggregation of TAGs, favoring the formation of dimers or oligomers that can substantially change the melting and crystallization profiles of these oils. In the present work the effect of ozonation on four different sunflower oils was studied: common sunflower, high oleic sunflower and two highly saturated sunflower oils, high palmitic and stearic in a high oleic background. Furthermore, the species of TAGs from the different oils that were affected by the ozone oxidative attack were studied. The formation of polar compounds and TAG aggregates were investigated as well as the effect caused by them on the physical properties of the oils as studied through differential scanning calorimetry. [ABSTRACT FROM AUTHOR]

Wild copepods are the main natural diet of marine finfish and they meet the larvae's requirements in phospholipids and essential fatty acids (EFA). While Artemia nauplii are an easier and more reliable live feed to produce in hatcheries for marine fish larvae than wild zooplankton, enrichment products commercially used lack phospholipids and essential long-chain polyunsaturated fatty acids (LC-PUFA). This is particularly true for docosahexaenoic acid (DHA) within their polar lipid fraction (PL DHA), which is critical to the survival and good development of the larvae. In this study, we showed that it is possible to increase the levels of phospholipids and DHA within the PL fraction of Artemia nauplii using marine lecithin through a process referred to as "boosting". A cheaper alternative to marine lecithin, soya lecithin, was also tested but resulted only in a significant increase of the phospholipid content of the nauplii with no positive effect on the essential LC-PUFA levels, due to the absence of LC-PUFA in the soya lecithin. This study also showed that the levels of PL DHA in the Artemia boosted with marine lecithin did not reflect the levels of PL DHA in the lecithin, highlighting there the complexity of the boosting process. Finally, chilling enriched Artemia nauplii at 5 °C for up to 10 h did not impact on their nutritional quality post-enrichment. Ultimately, this study proposes innovative and sound enrichment strategies to produce Artemia nauplii rich in EFA and/or PL, similarly to that of the wild copepods' lipid profile. • Boosting Artemia with lecithins increased the levels of phospholipids in the Artemia compared to the non-boosted nauplii. • The marine lecithin boosted Artemia exhibited three times more DHA among their polar lipids than in the other treatments. • Chilling enriched Artemia below 10 °C was shown to be an appropriate way to preserve their nutritional quality for up to 10 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fourteen polar lipid classes were identified by UHPLC-QTRAP-MS analysis. • A total of 362 lipid species were identified in mature breast milk and ewe milk. • 139 differentially expressed lipid species were screened out to evaluate the mammalian milk. • Sphingolipid metabolism and glycerophospholipid metabolism are pivotal metabolic pathways. • Our results provide a theoretical basis for optimizing milk-based infant formula. Polar lipids play essential biological functions in energy storage, both as structural components of cell membranes and as signaling molecules. In this study, a comprehensive UHPLC-QTRAP-MS-based lipidomic analysis of mature breast milk (BM) and ewe milk (EM) was conducted. Through the analysis, a total of 362 polar lipid species from 14 subclasses were characterized, including 60 phosphatidylethanolamines (PEs), 59 phosphatidylcholines (PCs), 38 phosphatidylinositols (PIs), 35 sphingomyelins (SMs), and 34 ceramides (Cers). Of these, 139 lipid molecules were screened as significantly differentially expressed polar lipids (SDPLs) between the two kinds of milk based on the following criteria: a variable importance in projection (VIP) value > 1.0, a false discovery rate-adjusted P -value < 0.0001, and a fold change (FC) of either > 2.0 or < 0.5; these included 111 upregulated and 28 downregulated SDPLs in EM compared to BM. Among these SDPLs, the content of PE (16:1_18:0) was found to be significantly higher in EM compared to BM (FC = 69.5853, P < 0.0001). Moreover, sphingolipid metabolism and glycerophospholipid metabolism were determined to be vital metabolic pathways. This was derived from the finding that PE, PC, SM, and PI were key lipid metabolites in the two kinds of milk that were related to these two metabolic pathways. This study provides new insights into the characterization of SDPLs in mammalian milk, and also provides a theoretical basis for optimizing infant formula. [ABSTRACT FROM AUTHOR]

Small pelagic fishes such as sardine and anchovy are among the richest species in essential fatty acids that are eicosapentaenoic acid (EPA) and docosahexaenoic acid (DHA), whose bioavailability may depend on its esterification to polar or neutral lipids. The EPA and DHA quantities in neutral and polar lipids were compared in sardine (from the English Channel) and anchovy (from the Bay of Biscay) fillets, and in red and white muscle separately. Sardine fillets had the highest EPA+DHA content (760 ± 670 vs 370 ± 510 mg/100 g in anchovy fillets), mainly because of their largest proportion of lipid-rich red muscle and its relatively high lipid content. However, DHA esterified to polar lipids was higher in anchovy than in sardine fillet (270 ± 60 vs 230 ± 30 mg/100 g). EPA+DHA content were higher in red than white muscle for both species. This study highlights the nutritional interest of red muscle to provide essential dietary fatty acids to consumers, and the necessity to consider its importance in nutrition studies. • Small pelagic fish are important sources of essential dietary fatty acids. • EPA+DHA contents are higher in sardine than in anchovy fillet. • EPA+DHA contents are higher in red that in white muscle. • DHA bounded to phospholipids is higher in anchovy than in sardine fillet. [ABSTRACT FROM AUTHOR]

Hazelnuts are a popular tree nut used whole or as an ingredient in a variety of bakery, candy and chocolate products. Based on the nutritional value and nutraceutical properties, mainly due to the lipid content, US Food and Drug Administration has recognized hazelnut as “heart-healthy” food. “Nocciola di Giffoni” is a Protected Geographical Indication (PGI) Italian hazelnut largely consumed but lacking of a comprehensive lipid profile. To acquire a detailed characterization of the polar lipids in fresh and roasted “Nocciola di Giffoni” hazelnut, an extensive analysis based on high-performance liquid chromatography coupled to multiple-stage linear ion-trap and orbitrap high-resolution mass spectrometry (LC-ESI/LTQOrbitrap/MS/MS n ) was carried out. This analytical approach (statistically validated) allowed for the detection of a wide range of polar lipids from oxylipins and long chain bases to high molecular weight lipids (phospholipids, sphingolipids, and glycolipids). Most of the polar lipids are here described for the first time in hazelnut. [ABSTRACT FROM AUTHOR]

Literary data on very long-chain fatty acids (VLCFAs) that are present in polar lipids of the plant cell membranes are discussed. Large amounts of VLCFA are found in polar lipids of some cellular organelles as well as in nonextractable lipids from diverse plant objects, where the influence of surface lipids on the relative content of these FAs is excluded. In some plants, the VLCFA fraction in membrane lipids increases under several kinds of stress. Amounts and diversity of VLCFAs are lower in flowering plants as compared with the representatives of more ancient taxons—gymnosperms, ferns, and marine algae. Presence of VLCFAs in the composition of annular lipids of the cell membranes is assumed. Biosynthesis of VLCFAs, enzymes involved in the process, and encoding genes are discussed. [ABSTRACT FROM AUTHOR]

Graphical abstract Highlights • Lipidomic profiles of raw and baked goat and sheep meat have been studied. • Anti-atherogenic activities of polar lipids of meat samples have been evaluated. • The most bioactive fractions of polar lipids have been studied by LC–MS. • The anti-anterogenic activities are due to phosphatidylcholine derivatives. • Sheep and goat meat are excellent sources of bioactive lipids against CVDs. Abstract The lipidomic profiles of goat and sheep meat were studied. Polar lipid fractions of raw and baked meat samples were tested for their in vitro anti-atherogenic properties. The total lipid (TL) content was extracted using the Bligh-Dyer method and was subsequently separated into total polar lipids (TPL) and total neutral lipids (TNL). The fatty acid profiles of the TPL and TNL of all three samples were determined by GC-FID. The TPL of all samples were further separated by preparative TLC into their constituent phospholipid and sphingolipid fractions. In all samples, polar lipid fraction 3 had a similar R f value to phosphatidylcholine. These phosphatidylcholine fractions were tested for their in vitro capacity to inhibit platelet-activating factor (PAF) induced platelet aggregation (anti-inflammatory activity) using human platelets. The phospholipid content of each fraction 3 was determined using LC–MS. These results provide a novel insight into the structure of phosphatidylcholine derivatives in goat and sheep meat and highlight the nutritional value of these meats in terms of their antithrombotic and cardioprotective properties before and after the baking process. [ABSTRACT FROM AUTHOR]

Lipid based formulations, endowed of long term stability as a result of the formation of lamellar liquid crystals, were prepared using the natural lipids lecithin and glycerol trioleate in water, and characterized using optical microscopy, SAXRD and NMR. The formulations, designed as possible carriers for lysozyme and caffeine, were evaluated for structural features and stability after the loading of the guest molecules. Release experiments were performed at 37 °C using the PBS medium. No burst release was observed either for lysozyme or caffeine. Although lysozyme released from the lipid formulations does not fully retain its biological activity, the investigated liquid crystal stabilized formulations display a promising potential as drug and cosmetic carriers for topical applications, due to their high biocompatibility. [ABSTRACT FROM AUTHOR]

Concomitant with increased lifespan, large segments of the population are experiencing cognitive decline, which might progress to Alzheimer’s disease (AD). Currently, there is no cure for AD and, once the neurodegenerative disorders are established, patients use pharmacologic therapy to slow the progression of the symptoms and require appropriate care to manage their condition. The preclinical stage of neural degeneration that progress through mild cognitive impairment (MCI) before the onset of AD is when it might be possible to introduce behavioral changes and pharma-nutritional interventions that modify the risk factors of MCI conversion to AD. Some food components accumulate in brain tissues, where they play essential roles. Among them, polar lipids, omega 3 fatty acids, and carotenoids appear to work additively or synergistically. Therefore, there is an opportunity to formulate nutraceuticals/functional foods to slow the progression of MCI. In this paper, we review the biochemical bases and recent interventions with bioactive lipids-rich formulations. Based on accumulated evidence, we propose that appropriate large-scale trials are warranted. [ABSTRACT FROM AUTHOR]

Thirty six male goats grazing Caatinga native pasture were randomly assigned to 4 concentrate supplementation levels (0, 5, 10 and 15 g/kg of body weight) and slaughtered after 120 days. Longissimus muscle meat lipids were extracted and fractionated into neutral (NL) and polar (PL) lipids. Supplementation of grazing goats increased linearly ( P < 0.05) intramuscular fat (1 to 1.5% of meat) and NL (0.3 to 1% of meat) but decreased linearly ( P = 0.044) the PL (0.66 to 0.50% of meat). On NL, supplementation increased linearly ( P = 0.047) the proportion of c 9-18:1 (31 to 40% of FA) with supplementation. On PL, supplementation reduced linearly ( P < 0.03) the dimethyl acetals, 18:3n-3 and most of long chain polyunsaturated FA (PUFA) proportions but increased linearly ( P < 0.001) the c 9-18:1. Considering the total meat FA, supplementation led to an increase of the saturated and monounsaturated FA contents and a decrease of the long chain n-6 and n-3 PUFA contents. [ABSTRACT FROM AUTHOR]

Abstract: The effects of two weaning diets and different weaning protocols on growth, survival, skeletal deformity and gut morphology of Atlantic cod larvae were studied in four groups from 16 to 45 days posthatch (dph). Cod larvae in groups 1 (early weaning with control diet) and 2 (early weaning with experimental diet) were used to evaluate the effects of different polar lipid content of weaning diets on larval and juvenile performance. Cod larvae in groups 2, 3 (early weaning with experimental diet + cofeeding with Artemia) and 4 (earlier weaning with experimental diet and earlier cofeeding with Artemia) were used to evaluate the effects of early introduction of dry diet and Artemia. From 45 to 170 dph, cod juveniles from all four groups were reared using a standard feeding protocol. No significant differences in growth, survival, deformities and gut morphology were found between cod larvae and juveniles from groups 1 and 2. Cod larvae fed on cofeeding regime with Artemia nauplii (groups 3 and 4) were bigger and had lower frequencies of jaw and neck deformities and higher foregut microvillus circumference than cod larvae from group 2. Our results demonstrate the importance of proper weaning protocols in producing better quality cod juveniles. [ABSTRACT FROM AUTHOR]

Bioactive lipids of the milk fat globule membrane become concentrated in two co-products of the butter industry, buttermilk and butterserum. Their lipid composition is detailed here with special emphasis on sphingolipid composition of nutritional interest, determined using GC, HPLC and tandem mass spectrometry. Butterserum was 2.5 times more concentrated in total fat than buttermilk, with 7.7 ± 1.5 vs 19.5 ± 2.9 wt% and even more concentrated in polar lipids, with 1.4 ± 0.2 vs 8.5 ± 1.1 wt%. Both ingredients constitute concentrated sources of sphingomyelin (3.4–21 mg/g dry matter) and contained low amounts of bioactive ceramides in a ratio to sphingomyelin of 1:5 mol% in buttermilk and 1:10 mol% in butterserum. Compared to other natural lecithins, these two co-products are rich in long and saturated fatty acids (C22:0-C24:0), contain cholesterol and could have interesting applications in neonatal nutrition, but also as brain-protective, hepatoprotective and cholesterol lowering ingredients. [ABSTRACT FROM AUTHOR]

Seasonal change of milk composition could offer opportunities for dairy manufacturers. A systematic survey on seasonal variation of six classes of polar lipids was conducted with 19 Holstein cows over the entire milking season using liquid chromatography-mass spectrometry technique. This study revealed that most polar lipid classes were positively correlated with the total fat content, but negatively correlated with fat globule size. All polar lipid classes displayed a large cow-to-cow variation as well as seasonal variation. All of the six classes showed a gradual increase over the milking season with the highest concentration observed in May (autumn). However, the proportion of different polar lipid classes remained constant during the entire milking season. This finding suggests that the production of polar lipids is highly regulated in the mammary gland. The implication of such a seasonal variation of polar lipids in the nutritional and technological aspects of milk is discussed. [ABSTRACT FROM AUTHOR]

Zinc is an essential micronutrient for all living cells. It serves as a structural and catalytic cofactor for numerous proteins, hence maintaining a proper level of cellular zinc is essential for normal functioning of the cell. Zinc homeostasis is sustained through various ways under severe zinc-deficient conditions. Zinc-dependent proteins play an important role in biological systems and limitation of zinc causes a drastic change in their expression. In budding yeast, a zinc-responsive transcription factor Zap1p controls the expression of genes required for uptake and mobilization of zinc under zinc-limiting conditions. It also regulates the polar lipid levels under zinc-limiting conditions to maintain membrane integrity. Deletion of ZAP1 causes an increase in triacylglyerol levels which is due to the increased biosynthesis of acetate that serves as a precursor for triacylglycerol biosynthesis. In this review, we expanded our recent work role of Zap1p in nonpolar lipid metabolism of budding yeast. [ABSTRACT FROM AUTHOR]

The authors describe a method for the extraction and determination of phospholipids (PLs) from human milk fat by using a molecularly imprinted polymer (MIP) as the sorbent material and liquid chromatography for detection. The MIP was synthesized by thermal polymerization using L-α-phosphatidylcholine (PC) as the template, methacrylic acid as the functional monomer, ethylene glycol dimethacrylate as the cross-linker, and acetonitrile as the porogenic solvent. The resulting MIP was employed as a sorbent for solid-phase extraction of PLs from human milk fat samples. The extracted PLs were then determined by means of hydrophilic interaction LC in combination with evaporative light scattering detection. Variables affect the extraction efficiency (such as the porogenic solvent, template/functional monomer/cross-linker ratio and extraction conditions) were optimized. The selectivity of the MIP over PLs different from PC was investigated, and the adsorption capacity, breakthrough volume and reusability of the MIP was determined. The MIP displays a satisfactory loading capacity (ca. 41 μg PC per g of sorbent) and a high affinity and selectivity for PC and structurally related PLs, such as sphingomyelin and L-α-phosphatidylethanolamine. The MIP can be reused at least 20 times in case of PL standards, and at least 6 times in case of human milk fat samples. [ABSTRACT FROM AUTHOR]

Marine microalgae exhibit a diversified phosphorus physiology and have also been recently found to show high inter-taxa variability in their phosphate induced-polar lipids’ remodelling. Identification of phosphorus physiology aspects that are more related to lipid remodelling can contribute to better understanding of such intricate phytoplankton lipid metabolism. Therefore, some aspects of phosphorus physiology related to its uptake, storage and use were evaluated in a taxonomically diversified group of nine marine microalgae that was arranged into three subgroups, each of them including species showing similar polar lipid responses to phosphate. Luxury phosphate uptake (PU) was the physiological aspect best associated to microalgal polar lipid metabolism as it was maximal in species ( Picochlorum atomus, Tetraselmis suecica and Nannochloropsis gaditana ) that were able to counterbalance between phospholipids (PL) and betaine lipids (BL). Cryptophytes ( Rhodomonas baltica, Chroomonas placoidea ), characterized by their constitutive BL and flexible PL contents in response to phosphate, had almost no luxury PU and showed higher phosphorus cell quota (Q P ) under phosphate deprivation. Haptophyes ( Isochrysis galbana, Diacronema vlkianum ), with constitutive BL contents and permanently minimal PL contents, showed the lowest Q P when deprived of phosphate while their luxury PU was below that for green microalgae. Induction of alkaline phosphatase activity following phosphate depletion was maximal in diatoms ( Phaeodactylum tricornutum, Chaetoceros gracilis ) and I. galbana but it was unrelated to lipid remodelling. Despite strong influence of taxonomy, polar lipid remodelling accounted for 38.8% of total variation when microalgae were ordinated using their physiological responses to phosphorus as descriptive variables. [ABSTRACT FROM AUTHOR]

Long-term kleptoplasty, the capability to retain functional stolen chloroplasts (kleptoplasts) for several weeks to months, has been shown in a handful of Sacoglossa sea slugs. One of these sea slugs is Elysia timida, endemic to the Mediterranean, which retains functional chloroplasts of the macroalga Acetabularia acetabulum. To understand how light modulates the lipidome of E. timida , sea slug specimens were subjected to two different 4-week light treatments: regular light and quasi-dark conditions. Lipidomic analyses were performed by HILIC-HR-ESI-MS and MS/MS. Quasi-dark conditions caused a reduction in the amount of essential lipids for photosynthetic membranes, such as glycolipids, indicating high level of kleptoplast degradation under sub-optimal light conditions. However, maximum photosynthetic capacities (F v / F m) were identical in both light treatments (≈0.75), showing similar kleptoplast functionality and suggesting that older kleptoplasts were targeted for degradation. Although more stable, the phospholipidome showed differences between light treatments: the amount of certain lipid species of phosphatidylethanolamine (PE), phosphatidylinositol (PI), and phosphatidylglycerol (PG) decreased under quasi-dark conditions, while other lipid species of phosphatidylcholine (PC), PE and lyso-PE (LPE) increased. Quasi-dark conditions promoted a decrease in the relative abundance of polyunsaturated fatty acids. These results suggest a light-driven remodelling of the lipidome according to the functions of the different lipids and highlight the plasticity of polar lipids in the photosynthetic sea slug E. timida. [Display omitted] • Light-driven remodelling of the lipidome of the photosynthetic animal Elysia timida • Dark conditions reduced the amount of essential lipids for photosynthetic membranes. • Maximum photosynthetic capacities (F v /F m) were identical in both light treatments. • Older kleptoplasts were targeted for degradation under dark conditions. • Dark conditions promoted a decrease in the relative abundance of PUFA. [ABSTRACT FROM AUTHOR]

Buttermilk, a byproduct of butter manufacturing, has gained considerable attention due to its high concentration of polar lipids as phospho- and sphingolipids from the milk fat globule membrane (MFGM). These polar lipids (PLs) are essential components of all cellular membranes and exert a variety of indispensable metabolic, neurological, and intracellular signaling processes. Despite its importance, there are few research studies that report a comprehensive characterization of the lipid molecular species of MFGM that could contribute to a better understanding of their putative healthful activities. In this study, procedures such as pressurized liquid extraction of polar and nonpolar lipids and their fractionation by flash chromatography have been carried out. The obtained fractions were submitted to an exhaustive characterization from a lipidomic point of view. The characterization includes new data about the identification and quantification of triacylglycerides (TAG), diacylglycerides (DAG), and phospho- and sphingolipids using different chromatographic techniques. The fatty acid profile was comparable to that of the milk fat but with a highly diverse composition of fatty acids. Molecular species have also been determined by using ultra-high performance liquid chromatography/quadruple-time-of-flight mass spectrometry (UPLC/QToF-MS). The TAG (16:0/16:0/6:0) and TAG (16:0/16:0/8:0) were the predominant saturated TAG species and TAG (14:0/18:1/16:0) and TAG (16:0/16:0/18:1) presented the highest content of monounsaturated TAG species. Furthermore; over 30 molecular species of phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), and phosphatidylinositol (PI) could be identified within PL, with PC (16:0/18:1) being the most abundant species. Whereas C16:0 was found to be the preferred FA in TAGs, it was C18:1 in PLs. Several ganglioside species have also been characterized with d18:1 ceramide moiety and secondary acyl chains ranging from C20:0 to C26:1. This approach could broaden the applications of high-resolution mass spectrometry for a better understanding of the role of MFGM and its functionality. [ABSTRACT FROM AUTHOR]

A hydrophilic interaction liquid chromatography (HILIC) fused-core column (150 × 2.1 mm ID, 2.7 μm particle size) and a short reversed-phase liquid chromatography (RPLC) column (20 mm × 2.1 mm ID, 1.9 μm) were serially coupled to perform mixed-mode chromatography (MMC) on complex mixtures of phospholipids (PL). Mobile phase composition and gradient elution program were, preliminarily, optimized using a mixture of phosphatidylcholines (PC), phosphatidylethanolamines (PE), their corresponding lyso-forms (LPC and LPE), and sphingomyelins (SM). Thus a mixture of PC extracted from soybean was characterized by MMC coupled to electrospray ionization (ESI) high-resolution Fourier-transform mass spectrometry (FTMS) using an orbital trap analyzer. Several previously undiscovered PC, including positional isomers (i.e. 16:0/19:1 and 19:1/16:0) of PC 35:1 and skeletal isomers (i.e. 18:1/18:2 and 18:0/18:3) of PC 36:3 were identified. Therefore, high-resolution MS/MS spectra unveiled the occurrence of isomers for several overall side chain compositions. The proposed MMC-ESI-FTMS/MS approach revealed an unprecedented capability in disclosing complexity of an actual lipid extract, thus representing a very promising approach to lipidomics. [ABSTRACT FROM AUTHOR]

Buttermilk is a dairy by-product with a high content of milk fat globule membranes (MFGMs), whose protein constituents are reported to be antiproliferative. Lipids represent about half of the composition of MFGM. The aim of this study was to isolate buttermilk lipid fractions and evaluate their potential antiproliferative effect. Selective extraction with food grade or non-food grade solvents was performed. Antiproliferative effectiveness of lipid extracts and their neutral and polar fractions was evaluated on nine human cancer cell lines. Fractions obtained using food grade ethanol gave a higher yield than those obtained using non-food grade solvents, and they effectively inhibited cell viability of the cancer cell lines investigated. These fractions, rich in phospho- and sphingolipids, were strongly antiproliferative against human ovary and colon cancer cells. This observation allowed us to hypothesize further analyses aimed at promoting the use of buttermilk polar lipid fractions as functional food additives. [ABSTRACT FROM AUTHOR]

Arctic species of Calanus are critical to energy transfer between higher and lower trophic levels and their relative abundance, and lipid content is influenced by the alternation of cold and warm years. All three species of Calanus were collected during different periods in Kongsfjorden (Svalbard, 79°N) and adjacent shelf during the abnormally warm year of 2006. Lipid composition and fatty acid structure of individual lipid classes were examined in relation with population structure. Wax esters dominated the neutral lipid fraction. Phosphatidylcholine (PC) dominated the structural lipids followed by phosphatidylethanolamine (PE). PC/PE ratios of 3-6 suggested an increase in PC proportions compared to earlier studies. Depending on the time scale, fatty acids of wax esters illustrated either trophic differences between fjord and offshore conditions for C. hyperboreus and C. finmarchicus or trophic differences related to seasonality for C. glacialis. Similarly, seasonality and trophic conditions controlled the changes in fatty acids of triglycerides, but de novo synthesis of long-chain monoenes suggested energy optimization to cope with immediate metabolic needs. Polar lipids fatty acid composition was species specific and on the long-term (comparison with data from the past decade) composition appears related to changes in trophic environment. Fatty acid composition of PC and PE indicated relative dominance of 20:5n-3 in PC and 22:6n-3 in PE for all three species. The combination of PE and PC acyl chain and phospholipid head group restructuring indicates an inter-annual variability and suggests that membrane lipids are the most likely candidate to evaluate adaptive changes in Arctic copepods to hydrothermal regime. [ABSTRACT FROM AUTHOR]

This study aimed to develop a sensitive and reliable normal-phase high-performance liquid chromatography–charged aerosol detector (NP-HPLC–CAD) method for direct and simultaneous quantification of diverse and complex lipid classes in marine samples. The 33-minute HPLC method so developed effectively separates 10 classes of non-polar and polar lipid. The quantitative calibration curves for all 10 lipid classes were built with satisfactory correlation coefficients (R 2 ≥ 0.9910), wide linear range (0.01–5.00 mg/mL), low limit of detection (LOD, 2–40 ng) and limit of quantification (LOQ, 4–80 ng). The precision (relative standard deviation of 2.33–7.13 %) and recovery rate (83.69–108.06 %) for the quantitative method met the acceptance criteria of FDA guidelines. Finally, the NP-HPLC–CAD method was successfully used to analyze marine lipid samples from abalone, oyster, scallop, mussel and Antarctic krill. Results show complex lipid composition of marine samples, mainly containing triacylglycerol, phosphatidylethanolamine and phosphatidylcholine. [Display omitted] • A rapid NP-HPLC–CAD method for direct quantification of lipids was developed. • The established method satisfied validation parameters. • The method was sensitive, easy to apply, accurate and reliable. • The method may be used for routine monitoring of lipids in marine samples. [ABSTRACT FROM AUTHOR]

• Phospholipids and milk fat globules were compared between five mammalian milk. • Human milk contains a higher amount of sphingomyelin than other mammalian milk. • The phospholipids acyl chain unsaturation are highest in human milk. • Milk fat globules mean size and distribution showed obvious differences across species. • A similar TAG core-membrane lipid structure was observed in all mammalian milk. We compared phospholipids (PLs) content, their molecular species, and milk fat globules size and microstructure in the milk of five mammalian species, including human, cow, goat, yak, and donkey. The absolute quantification of major PLs was determined using 31P NMR and their fatty acid composition with GC. The molecular species of PLs were analysed using LC-MS where a total of 9 PL species, including one sphingomyelin (SM), six glycerophospholipid (GPL), and two lysoglycerophospholipids (lyso-GPLs), were identified. PLs profile shows an obvious difference among the species, with human milk showing higher SM content and more unsaturated fatty acyls than other mammalian milk. The mammalian milk show a similar core-membrane lipid structure but obvious different size distribution. These data provide a basis for better construction of infant formulas to provide PLs requirements and a similar milk fat globule structure for infants. [ABSTRACT FROM AUTHOR]

[Display omitted] • TAG, PE and SM accounted for 79.78% of the total molecular species number (132 ± 30). • The energy supply, PUFA-containing PLs and choline were low from the lipids of Tibetan human milk. • The comparison of lipid contents was OPO > OPL, PC34:2 > PC36:2 and SM34:1:2 > SM42:2:2. • Tibetan human milk possessed high contents of OCFAs-containing TAGs. • The contents of TAGs and DAGs with PUFAs were low in Tibetan human milk. The unique geographical characteristics and food culture of Tibet can affect the nutrition of human milk lipids. But little has been done in the comparison of the lipids between Tibet and other areas. This study gives in-depth analysis of the species, concentration and composition of lipid subclasses at the molecular level of the Tibetan human milk. There were averagely 132 ± 30 species of lipids, among which triglycerides (TAGs), phosphatidylethanolamine (PE) and sphingomyelin (SM) accounted for 79.78% of the total species number in the Tibetan human milk samples. The contents of TAG, SM, phosphatidylcholine (PC), and PE in the Tibetan human milk were 85.84%, 17.79%, 25.94% and 55.81% of those in the comparative human milk of China, respectively. The contents of TAGs and diglycerides (DAGs) with PUFAs in Tibetan human milk were significantly lower than those in the comparative group. However, the content and percentage of TAGs and DAGs with odd-chain saturated fatty acids were both higher in the Tibetan human milk than those in the comparative human milk. In total, 18 molecular species of lipids were downregulated and 5 ones were upregulated in the Tibetan human milk compared with those in the comparative human milk of China. The profile of lipids in the Tibetan human milk at the molecular level provided the scientific basis for maternal diet and supplemented the Chinese human milk lipids database. [ABSTRACT FROM AUTHOR]