Phospholipid Molecular Species Research Articles

Comprehensive analysis of phospholipids in pumpkin (Cucurbita maxima) seeds: Comparison with cashew nuts and almonds

Pumpkin (Cucurbita maxima) seeds have gained increasing attention due to their high nutraceutical value; however, data regarding the phospholipid (PL) profile of this oily seed are scarce. Through the combination of RPLC-MS/MS, HILIC-MS, and Paternò-Büchi photochemical reaction, we comprehensively characterized PLs in three accessions of pumpkin seeds. We identified a total of 183 PL molecular species across eight classes. Phosphatidylcholine (PC) represents the most abundant class, followed by phosphatidylinositol (PI), phosphatidylglycerol (PG), and phosphatidic acid (PA). The total PL content is comparable to that of almonds and cashew nuts. In terms of PL structures, pumpkin seeds feature a higher abundance of C18:2-containing PL isomers, a preferential esterification of C18:1 and C18:2 at the sn-2 position as well as a predominant Δ9/Δ9,12 double bond locations for C18:1 and C18:2 respectively. This is the first systematic study on PLs of pumpkin seeds to our knowledge. Our findings add further evidence on the potential value of pumpkin seeds as a functional food or as a source material for making plant-based drink.

Membrane vectorial lipidomic features of coral host cells’ plasma membrane and lipid profiles of their endosymbionts Cladocopium

The symbiotic relationships between coral animal host and autotrophic dinoflagellates are based on the mutual exchange and tight control of nutritional inputs supporting successful growth. The corals Sinularia heterospiculata and Acropora aspera were cultivated using a flow-through circulation system supplying seawater during cold and warm seasons of the year, then sorted into host cells and symbionts and subjected to phylogenetic, morphological, and advanced lipid analyses. Here we show, that the lipidomes of the dinoflagellates Cladocopium C1/C3 and acroporide-specific Cladocopium hosted by the corals, are determined by lipidomic features of different thermosensitivity and unique betaine- and phospholipid molecular species. Phosphatidylserines and ceramiaminoethylphosphonates are not detected in the symbionts and predominantly localized on the inner leaflet of the S. heterospiculata host plasma membrane. The transmembrane distribution of phosphatidylethanolamines of S. heterospiculata host changes during different seasons of the year, possibly contributing to mutualistic nutritional exchange across this membrane complex to provide the host with a secure adaptive mechanism and ecological benefits.

A Comparative Study on the Composition and Structure of Human Milk Phospholipids and its Natural Resources: Based on a Similarity Evaluation Model

Human milk phospholipids (HMPLs) play an indispensable role in the neurodevelopment and growth of infants. In this study, a total of 37 phospholipid fatty acid (PLFA) species and 139 phospholipid molecular species were detected from human milk and other natural phospholipid sources (including 5 animal-derived species and 2 plant species). Moreover, a similarity evaluation model for HMPLs was established, including phospholipid classes, PLFAs, and phospholipid molecular species, to evaluate their natural substitutes. The closest scores for HMPL substitute in these three dimensions was 0.89, 0.72, and 0.77, which belonged to mare milk, goat milk, and camel milk, respectively. The highest comprehensive similarity score was obtained by camel milk at 0.75, while the lowest score was observed in soybean phospholipid (0.22). Therefore, these results not only monitored the stereochemical structure of HMPLs and their substitutes, but also further provided new insights for the development of infant formulae.

Characterization of phospholipidome in milk, yogurt and cream, and phospholipid differences related to various dairy processing methods

Milk phospholipids have multiple health benefits, but the deficiency of detailed phospholipid profiles in dairy products brings obstacles to intake calculation and function evaluation of dairy phospholipids. In present study, 306 phospholipid molecular species were identified and quantified among 207 milk, yogurt and cream products using a HILIC-ESI-Q-TOF MS and a HILIC-ESI-QQQ MS. The phospholipid profiles of five mammals' milk show that camel milk contains the most abundant phosphatidylethanolamine, phosphatidylserine and sphingomyelin; cow, yak and goat milk have similar phospholipidomes, while buffalo milk contains abundant phosphatidylinositol. Fewer plasmalogens but more lyso-glycerolphospholipids were found in ultra-high-temperature (UHT) sterilized milk than in pasteurized milk, and higher proportions of lyso-glycerolphospholipid/total phospholipid were observed in both cream and skimmed/semi-skimmed milk than whole milk, indicating that UHT and skimming processes improve glycerolphospholipid degradation and phospholipid nutrition loss. Meanwhile, more diacyl-glycerolphospholipids and less of their degradation products make yogurt a better phospholipid resource than whole milk.

The Association between the Plasma Phospholipid Profile and Insulin Resistance: A Population-Based Cross-Section Study from the China Adult Chronic Disease and Nutrition Surveillance.

The dysfunction of phospholipid metabolism enzymes and the change in membrane phospholipid composition are associated with insulin resistance, indicating that phospholipids play an important role in the regulation of insulin sensitivity. The reflection of phospholipid changes in blood might provide clues for both mechanism understanding and intervention. Using a targeted phospholipidomic approach, 199 phospholipid molecular species were identified and quantified in the plasma of 1053 middle-aged participants from a national investigation. The associations of the phospholipid matrix, clusters, and molecular species with insulin resistance were investigated. A significant association was confirmed between the phospholipid matrix and the homeostatic-model assessment of insulin resistance (HOMA-IR) by a distance-based linear model. Furthermore, three clustered phospholipid modules and 32 phospholipid molecular species were associated with HOMA-IR with the strict control of demographic and lifestyle parameters, family history of diabetes, BMI, WC, and blood lipid parameters. The overall decline in lysophosphatidylcholines (LPCs), the decrease in saturated lysophosphatidylethanolamines (LPEs), the decrease in polyunsaturated/plasmenyl phosphatidylcholines (PCs), and the increase in polyunsaturated phatidylethanolamines (PEs) were the prominent characters of plasma phospholipid perturbation associated with insulin resistance. This suggested that PC- and PE-related metabolic pathways were widely involved in the process of insulin resistance, especially the disorder of LPC acylation to diacyl-PC.

Lipidomics reveals the effect of hot-air drying on the quality characteristics and lipid oxidation of Tai Lake whitebait (Neosalanx taihuensis Chen)

The present study aimed to investigate the impact of temperature on the quality attributes, particularly lipid oxidation and phospholipid molecular species, of Tai Lake whitebait during hot-air drying. Fresh samples of Tai Lake whitebait were subjected to heat treatment and were dried at temperatures of 40, 50, 60, and 70 °C for 12 h. The results indicated significant and continuous increases in peroxide values (POV), thiobarbituric acid reactive substances (TBARS), and saturated fatty acids (SFA) contents during hot-air drying, but reductions in monounsaturated fatty acids (MUFA). During the hot-air drying process, the mass fraction of triacylglycerol (TAG) and phospholipid (PoL) decreased, while the fractions of diacylglycerol (DAG), monoacylglycerol (MAG) and free fatty acid (FFA) increased. Furthermore, the drying treatment led to a more pronounced reduction in Phosphocholine (PC) content compared to phoethanolamine (PE). A total of 17 phosphatidylcholines (PC), 18 phosphatidylethanolamine (PE), 7 phosphatidylinositol (PI), and 9 phosphatidylserine (PS) molecular species were identified. By comprehensively considering the drying time and quality attributes, 50 °C was selected the ideal temperature for drying. The findings of the investigation revealed that thermal drying significantly influenced the quality attributes and lipid oxidation of Tai Lake whitebait. The insights gained from this study are valuable for improving the drying process for Tai Lake whitebait and enhancing its overall quality.

Changes of Phospholipid Molecular Species Profile Upon Bleaching and Subsequent Restoration of Coral Sinularia heterospiculata

Changes of Phospholipid Molecular Species Profile Upon Bleaching and Subsequent Restoration of Coral Sinularia heterospiculata

Cardiac lipidomic profiles in mice undergo changes from fetus to adult

AimsLipids are essential cellular components with many important biological functions. Disturbed lipid biosynthesis and metabolism has been shown to cause cardiac developmental abnormality and cardiovascular diseases. In this study, we aimed to investigate the composition and the molecular profiles of lipids in mammalian hearts between embryonic and adult stages and uncover the underlying links between lipid and cardiac development and maturation. Materials and methodsWe collected mouse hearts at the embryonic day 11.5 (E11.5), E15.5, and the age of 2 months, 4 months and 10 months, and performed lipidomic analysis to determine the changes of the composition, molecular species, and relative abundance of cardiac lipids between embryonic and adult stages. Additionally, we also performed the electronic microscopy and RNA sequencing in both embryonic and adult mouse hearts. Key findingsThe relative abundances of certain phospholipids and sphingolipids including cardiolipin, phosphatidylglycerol, phosphatidylethanolamine, and ceramide, are different between embryonic and adult hearts. Such lipidomic changes are accompanied with increased densities of mitochondrial membranes and elevated expression of genes related to mitochondrial formation in adult mouse hearts. We also analyzed individual molecular species of phospholipids and sphingolipids, and revealed that the composition and distribution of lipid molecular species in hearts also change with development. SignificanceOur study provides not only a lipidomic view of mammalian hearts when developing from the embryonic to the adult stage, but also a potential pool of lipid indicators for cardiac cell development and maturation.

Shotgun-Based Mass Spectrometry Analysis of Phospholipid and Triacylglycerol Molecular Species and Eicosanoids in Salmon Muscle Tissue on Feeding Microbial Oil.

The continuous growth of aquaculture places a growing demand on alternative sources of fish oil (FO). Certain microorganisms provide a sustainable replacement for FO due to their content of EPA and DHA, which are essential for fish health. Appreciable evidence shows that changes in feeding sources may alter the nutritional components of salmon; however, the influence of diets on lipid species remains unclear. In this study, the identification and semi-quantification of lipid molecular species in salmon muscle during feeding with a microbial oil (MO) were carried out by focusing on triacylglycerol (TAG) and diacyl-phospholipid using shotgun-based mass spectrometry analysis. DHA in the MO diet was efficiently incorporated into phospholipid structures on feeding, followed by accumulation in salmon muscle. The MO diet elevated the level of certain EPA-containing TAGs, such as TAG C52:5 (16:0_16:0_20:5) and TAG C54:6 (16:0_18:1_20:5), indicating that the MO diet may be an excellent source for enhancement of the abundance of ω3 lipids. Further, prostaglandins (PGs) PGE2 and PGF3α were identified and quantified for the first time in salmonid tissue.

Dynamics of Docosahexaenoic Acid Utilization by Mouse Peritoneal Macrophages.

In this work, the incorporation of docosahexaenoic acid (DHA) in mouse resident peritoneal macrophages and its redistribution within the various phospholipid classes were investigated. Choline glycerophospholipids (PC) behaved as the major initial acceptors of DHA. Prolonged incubation with the fatty acid resulted in the transfer of DHA from PC to ethanolamine glycerophospholipids (PE), reflecting phospholipid remodeling. This process resulted in the cells containing similar amounts of DHA in PC and PE in the resting state. Mass spectrometry-based lipidomic analyses of phospholipid molecular species indicated a marked abundance of DHA in ether phospholipids. Stimulation of the macrophages with yeast-derived zymosan resulted in significant decreases in the levels of all DHA-containing PC and PI species; however, no PE or PS molecular species were found to decrease. In contrast, the levels of an unusual DHA-containing species, namely PI(20:4/22:6), which was barely present in resting cells, were found to markedly increase under zymosan stimulation. The levels of this phospholipid also significantly increased when the calcium-ionophore A23187 or platelet-activating factor were used instead of zymosan to stimulate the macrophages. The study of the route involved in the synthesis of PI(20:4/22:6) suggested that this species is produced through deacylation/reacylation reactions. These results define the increases in PI(20:4/22:6) as a novel lipid metabolic marker of mouse macrophage activation, and provide novel information to understand the regulation of phospholipid fatty acid turnover in activated macrophages.

Comparative studies on the lipid profiles of female and male gonads of abalone (Haliotis discus hannai)

AbstractLipid profiles of the lipids from female gonads (LFG) and male gonads (LMG) of abalones (Haliotis discus hannai) were evaluated based on the analysis of phospholipid (PL) molecular species, PL class composition, fatty acid (FA) composition, and lipid class composition. These results suggested that lipids from abalone gonads were abundant in omega‐3 polyunsaturated FA (n − 3 PUFA, 14.42%–18.27% of total FAs) and PLs including phosphatidylcholine (PC, 21.26–47.85 mg g−1) and phosphatidylethanolamine (PE, 9.29–24.10 mg g−1). Furthermore, more than 60 molecular species of PC and PE were determined. Particularly, the molecular species containing n − 3 PUFA including eicosapentaenoic acid (EPA) constituted majority of PC and PE in LFG and LMG. By contrast, LFG contained more PC and PE species containing EPA. Considering the lipid profiles, abalone gonads are a potential source of PL‐form n − 3 PUFA.

Characterization and comparison of phospholipid fatty acids and molecular species in different animal milk

Phospholipids are increasingly recognized as nutrients with potential health benefits, but comparative studies on the composition of phospholipids in different animal milk have not been thorough. In this study, phospholipid composition of four types of animal milks from cow, goat, donkey, and yak was measured, and 33 fatty acids and 74 molecular species of phospholipids were found. Among the four types of animal milks, C16:0, C18:0, and C18:1 were the major fatty acids of phospholipids, and the fatty acids were mainly saturated fatty acids. Additionally, the molecular species of phospholipids in various animal milk differed, and 18:0/18:2 was the most abundant molecular species. Furthermore, significantly different phospholipid molecular species of each group were screened out. The results reported herein will contribute to understanding the differences in functional and nutritional properties of phospholipids from different animal milks which can enhance the utilization of various animal milk sources.

Effects of different degumming processes on the molecular species and microstructures of phospholipids recovered from crude vegetable oils

Phospholipids (PLs), as natural additives and nutritional supplements, are recovered from the gum phase during the degumming process of crude vegetable oils. The molecular species of phospholipids recovered from crude soybean (SO), flaxseed (FO) and peanut oil (PO) by different degumming processes, including water (WD), acid (AD), PLA1(EDA), PLC (EDC) and PLA1-PLC (EDAC) were investigated. According to the PLS-DA model, a total of 30, 38 and 21 characteristic markers were identified using UPLC-Q-TOF-MS in the phospholipids recovered from SO, FO and PO by different degumming processes, respectively. PC (18:2/18:2) and PE (18:2/18:2) were the main phospholipids for WD and AD, LPC (18:2) and LPE (18:2) were the main phospholipids for EDA and EDAC, and PI (16:0/18:2) and PI (16:0/18:1) were served as characteristic phospholipids for EDC. In addition, a lamellar liquid-crystalline phase was observed in the recovered phospholipids, which indicated that the microstructure of phospholipids recovered from crude vegetable oils were significantly influenced by different degumming processes. These differential molecular species of phospholipid products provide useful information to facilitate the potential utilization of phospholipid products as emulsifiers in food and as ingredients in the pharmaceutical industries.

Using MetaboAnalyst to introduce undergraduates to lipidomic analysis and lipid remodeling in barley roots.

Lipidomics is a discipline that focuses on the identification and quantification of lipids. Although a part of the larger omics field, lipidomics requires specific approaches for the analysis and biological interpretation of datasets. This article presents a series of activities for introducing undergraduate microbiology students to lipidomic analysis through tools from the web-based platform MetaboAnalyst. The students perform a complete lipidomic workflow, which includes experiment design, data processing, data normalization, and statistical analysis of molecular phospholipid species obtained from barley roots exposed to Fusarium macroconidia. The input data are provided by the teacher, but students also learn about the methods through which they were originally obtained (untargeted liquid chromatography coupled with mass spectrometry). The ultimate aim is for students to understand the biological significance of phosphatidylcholine acyl editing. The chosen methodology allows users who are not proficient in statistics to make a comprehensive analysis of quantitative lipidomic datasets. We strongly believe that virtual activities based on the analysis of such datasets should be incorporated more often into undergraduate courses, in order to improve students' data-handling skills for omics sciences.

Shotgun lipidomics reveals the changes in phospholipids of brown rice during accelerated aging

Brown rice exhibits higher nutritional value and attracts more and more attentions; however, the change in phospholipid molecular species in brown rice during aging is poorly understood. In this study, shotgun lipidomics was employed to investigate the changes in phospholipid molecular species in four brown rice varieties (two japonica rice and two indica rice) during accelerated aging. A total of 64 phospholipid molecular species were identified, and most of them were rich in polyunsaturated fatty acids. For japonica rice, phosphatidylcholine (PC), phosphatidylethanolamine (PE), and phosphatidylglycerol (PG) gradually decreased during accelerated aging. However, the content of PC, PE, and PG in indica rice showed no difference during accelerated aging. Significantly different phospholipid molecular species from four brown rice were screened during accelerated aging. Based on these significantly different phospholipids, the metabolic pathways including glycerophospholipid metabolism and linoleic acid metabolism during accelerated aging were depicted. The findings from this study could be helpful in explaining the impact of accelerated aging on phospholipids of brown rice, and offer an understanding on relationships between phospholipids degradation and brown rice deterioration.

Effects of high-sugar, high-cholesterol, and high-fat diet on phospholipid profile of mouse tissues with a focus on the mechanism of plasmalogen synthesis

High-sugar diet (HSD), high-cholesterol diet (HCD), and high-fat diet (HFD) all modulate the levels of lipids. However, there is a lack of comparative data on the effects of different diets on phospholipids (PLs). Given their important role in physiology and disease, there has been an increasing focus on altered PLs in liver and brain disorders. This study aims to determine the effects of HSD, HCD, and HFD for 14-week feeding on the PL profile of the mouse liver and hippocampus. Quantitative analysis of 116 and 113 PL molecular species in liver and hippocampus tissues revealed that the HSD, HCD, and HFD significantly affected the PLs in liver and hippocampus, especially decreased the levels of plasmenylethanolamine (pPE) and phosphatidylethanolamine (PE). Overall, the impact of HFD on liver PLs was more significant, consistent with the morphological changes in the liver. Compared to HSD and HCD, HFD induced a significant decrease in PC (P-16:0/18:1) and an increase in LPE (18:0) and LPE (18:1) in liver. In the liver of mice fed with different diets, the expression of the key enzymes Gnpat, Agps in the pPE biosynthesis pathway and peroxisome-associated membrane proteins pex14p were decreased. In addition, all diets significantly reduced the expression of Gnpat, pex7p, and pex16p in hippocampus tissue. In conclusion, HSD, HCD, and HFD enhanced lipid accumulation in the liver, led to liver injury, significantly affected the liver and hippocampus PLs, and decreased the expression of genes related to plasmalogen synthesis in mouse liver and hippocampus, which caused severe plasmalogen reduction.

Coral Lipidome: Molecular Species of Phospholipids, Glycolipids, Betaine Lipids, and Sphingophosphonolipids.

Coral reefs are the most biodiversity-rich ecosystems in the world's oceans. Coral establishes complex interactions with various microorganisms that constitute an important part of the coral holobiont. The best-known coral endosymbionts are Symbiodiniaceae dinoflagellates. Each member of the coral microbiome contributes to its total lipidome, which integrates many molecular species. The present study summarizes available information on the molecular species of the plasma membrane lipids of the coral host and its dinoflagellates (phosphatidylcholine (PC), phosphatidylethanolamine (PE), phosphatidylserine (PS), phosphatidylinositol (PI), ceramideaminoethylphosphonate, and diacylglyceryl-3-O-carboxyhydroxymethylcholine), and the thylakoid membrane lipids of dinoflagellates (phosphatidylglycerol (PG) and glycolipids). Alkyl chains of PC and PE molecular species differ between tropical and cold-water coral species, and features of their acyl chains depend on the coral's taxonomic position. PS and PI structural features are associated with the presence of an exoskeleton in the corals. The dinoflagellate thermosensitivity affects the profiles of PG and glycolipid molecular species, which can be modified by the coral host. Coral microbiome members, such as bacteria and fungi, can also be the source of the alkyl and acyl chains of coral membrane lipids. The lipidomics approach, providing broader and more detailed information about coral lipid composition, opens up new opportunities in the study of biochemistry and ecology of corals.

Analysis of soybean phospholipids based on liquid chromatography-ion trap-time of flight-mass spectrometry

Using liquid chromatography-ion trap-time of flight-mass spectrometry to establish a soybean phospholipids(PL) analysis method, carry out comprehensive structural identification and quantitative analysis of soybean PL molecule species, and obtain soybean PL molecular composition and content data. The PL profiles of 10 soybean varieties cultivated in northeast China were determined by a hydrophilic interaction liquid chromatography-ion trap-time of flight-mass spectrometry(HILIC-ESI-IT-TOF-MS) system. The hydrophilic interaction liquid chromatography realized class separation of PLs, and ion trap-time of flight-mass spectrometry realized the estimation of head group type, fatty acyl structure, and substituent position. The identified PL molecule species were quantified using accurate mass extraction and internal standard method. A total of 101 PL molecular species from 11 classes were estimated in soybean seeds, including 20 phosphatidylcholines(PC), 15 phosphatidylethanolamines(PE), 17 phosphatidylinositols(PI), 12 phosphatidylglycerols(PG), 9 phosphatidic acids(PA), 6 phosphatidylserines(PS), 5 lysophosphatidylcholines(LPC), 5 lysophosphatidylethanolamines(LPE), 6 lysophosphatidylinositols(LPI), 4 lysophosphatidylglycerols(LPG) and 2 lysophosphatidicacids(LPA). The limits of detection for the target object were ≤ 60 ng/mL and R~2 were all >0.99. The total concentration of PL ranged from 6873.1 to 12 678.6 μg/g in detected soybeans. Generally, most of the detected soybean cultivars were great resources of PL, especially SN-29, SN-61, HN-40 and DN-690. The concentrations of PC and PE in the tested soybean were higher, followed by PI, PG, PA and PS. Among the lysophospholipids, the concentration of LPC was the highest, followed by LPE, LPI, LPG and LPA. The soybean PL component analysis method established based on the HILIC-IT-TOF-MS system can achieve good separation of various types of PL, and can accurately characterize the head group type, fatty acyl structure and substituent position of PL molecule species. The molecular composition and content data of soybean PL were obtained.

Component and Content of Lipid Classes and Phospholipid Molecular Species of Eggs and Body of the Vietnamese Sea Urchin Tripneustes gratilla.

Sea urchins (Tripneustes gratilla) are among the most highly prized seafood products in Vietnam because of their nutritional value and medicinal properties. In this research, lipid classes and the phospholipid (PL) molecular species compositions from the body and eggs of T. gratilla collected in Hon Tam, Nha Trang, Khanh Hoa, Vietnam, were investigated. Hydrocarbon and wax (HW), triacylglycerol (TG), mono- and diacylglycerol (MDAG), free fatty acid (FFA), sterol (ST), polar lipid (PoL), and monoalkyl-diacylglycerol are the major lipid classes. In PL, five main glycerophospholipid classes have been identified, in which 137 PL molecular species were detected in the body and eggs of T. gratilla, including 20 inositol glycerophospholipids (PI), 11 serine glycerophospholipids (PS), 22 ethanolamine glycerophospholipids (PE), 11 phosphatidic acids (PA), and 73 choline glycerophospholipids (PC). PI 18:0/20:4, PS 20:1/20:1, PE 18:1e/20:4, PA 20:1/20:1, and PC 18:0e/20:4 are the most abundant species with the highest content values of 38.65-48.19%, 42.48-44.41%, 41.21-40.03%, 52.42-52.60%, and 7.77-7.18% in each class of the body-eggs, respectively. Interestingly, PL molecules predominant in the body sample were also found in the egg sample. The molecular species with the highest content account for more than 40% of the total species in each molecular class. However, in the PC class containing 73 molecular species, the highest content species amounted to only 7.77%. For both the body and egg TL samples of the sea urchin T. gratilla, a substantial portion of C20:4n polyunsaturated fatty acid was found in PI, PE, and PC, but C16, C18, C20, and C22 saturated fatty acids were reported at low levels. The most dominant polyunsaturated fatty acid in PI, PE, and PC was tetracosapolyenoic C20, while unsaturated fatty acid C20:1 was the most dominant in PS and PA. To our knowledge, this is the first time that the chemical properties of TL and phospholipid molecular species of the PoL of Vietnamese sea urchin (T. gratilla) have been studied.

Design of high-monounsaturated fatty acid soybean seed oil using GmPDCTs knockout via a CRISPR-Cas9 system.

Design of high-monounsaturated fatty acid soybean seed oil using GmPDCTs knockout via a CRISPR-Cas9 system.