Main Phospholipids Research Articles

Comparative characteristics of the lipidome of Cycas revoluta and C. rumphii (Cycadaceae)

A targeted lipidomics analysis of four classes of membrane glycerolipids was carried out in two species of Cycadaceae from the genus Cycas – C. revoluta and C. rumphii. The analysis of the molecular diversity of the main phospholipids, which are the components of extra-chloroplast membranes, has revealed archaic features, including a high level of molecular species containing C18:1 fatty acids (typical of Ginkgo biloba), increased relative content of molecular species with odd fatty acids C17:0 and C19:0 (typical of non-seed plants). At the same time, the analysis of the molecular diversity of the glycolipids which are the components of chloroplast membranes, did not find significant differences from most seed plants, which indicates a higher conservation of lipids of a photosynthetic apparatus. The identified features of the molecular composition of glycerolipids of two species of Cycas indicate the prospectiveness of using lipidomics for taxonomic and phylogenetic studies, with the data on the molecular composition of phosphatidylcholines, for which the greatest heterogeneity and species-specificity was demonstrated, deserving the most attention.

Investigation of Antioxidant Activity of Protein Hydrolysates from New Zealand Commercial Low-Grade Fish Roes.

The objective of this study was to investigate the nutrient composition of low-grade New Zealand commercial fish (Gemfish and Hoki) roe and to investigate the effects of delipidation and freeze-drying processes on roe hydrolysis and antioxidant activities of their protein hydrolysates. Enzymatic hydrolysis of the Hoki and Gemfish roe homogenates was carried out using three commercial proteases: Alcalase, bacterial protease HT, and fungal protease FP-II. The protein and lipid contents of Gemfish and Hoki roes were 23.8% and 7.6%; and 17.9% and 10.1%, respectively. The lipid fraction consisted mainly of monounsaturated fatty acid (MUFA) in both Gemfish roe (41.5%) and Hoki roe (40.2%), and docosahexaenoic (DHA) was the dominant polyunsaturated fatty acid (PUFA) in Gemfish roe (21.4%) and Hoki roe (18.6%). Phosphatidylcholine was the main phospholipid in Gemfish roe (34.6%) and Hoki roe (28.7%). Alcalase achieved the most extensive hydrolysis, and its hydrolysate displayed the highest 2,2-dipheny1-1-picrylhydrazyl (DPPH)˙ and 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) (ABTS) radical scavenging activities and ferric reducing antioxidant power (FRAP). The combination of defatting and freeze-drying treatments reduced DPPH˙ scavenging activity (by 38%), ABTS˙ scavenging activity (by 40%) and ferric (Fe3+) reducing power by18% (p < 0.05). These findings indicate that pre-processing treatments of delipidation and freeze-drying could negatively impact the effectiveness of enzymatic hydrolysis in extracting valuable compounds from low grade roe.

Rhamnolipids and fengycins interact differently with biomimetic lipid membrane models of Botrytis cinerea and Sclerotinia sclerotiorum: Lipidomics profiles and biophysical studies

Rhamnolipids (RLs) and Fengycins (FGs) are biosurfactants with very promising antifungal properties proposed to reduce the use of synthetic pesticides in crops. They are amphiphilic molecules, both known to target the plasma membrane. They act differently on Botrytis cinerea and Sclerotinia sclerotiorum, two close Sclerotiniaceae phytopathogenic fungi. RLs are more efficient at permeabilizing S. sclerotiorum, and FGs are more efficient at permeabilizing B. cinerea mycelial cells. To study the link between the lipid membrane composition and the activity of RLs and FGs, we analyzed the lipid profiles of B. cinerea and S. sclerotiorum. We determined that unsaturated or saturated C18 and saturated C16 fatty acids are predominant in both fungi. We also showed that phosphatidylethanolamine (PE), phosphatidic acid (PA), and phosphatidylcholine (PC) are the main phospholipids (in this order) in both fungi, with more PA and less PC in S. sclerotiorum. The results were used to build biomimetic lipid membrane models of B. cinerea and S. sclerotiorum for all-atom molecular dynamic simulations and solid-state NMR experiments to more deeply study the interactions between RLs or FGs with different compositions of lipid bilayers. Distinctive effects are exerted by both compounds. RLs completely insert in all the studied model membranes with a fluidification effect. FGs tend to form aggregates out of the bilayer and insert individually more easily into the models representative of B. cinerea than those of S. sclerotiorum, with a higher fluidification effect. These results provide new insights into the lipid composition of closely related fungi and its impact on the mode of action of very promising membranotropic antifungal molecules for agricultural applications.

Characterization of flavour components and identification of lipid flavour precursors in different cuts of pork by phospholipidomics

The lipids and volatile compounds in pork from different parts, including the loin, belly, shoulder and hind leg were analyzed by triple quadrupole tandem time-of-flight mass spectrometer (Q-TOF/MS) and gas chromatography-olfactometry-mass spectrometry (GC-O-MS), respectively. Partial least squares regression (PLSR) and Pearson correlation analysis were utilized to establish the relationship between the lipids and volatile compounds. A total of 8 main flavour substances, 38 main phospholipids, and 32 main fatty acids were identified. The results showed that the key flavour compounds were mainly derived from unsaturated fatty acids and phospholipids containing unsaturated fatty acids, including oleic acid (C18:2n6c), α-Linolenic acid (C18:3n3), arachidonic acid (C20:4n6), PE O (18:1/20:4), PE O (18:2/20:4), and PE O (18:2/18:2), etc. Understanding the relationship between flavour compounds and lipids of pork will be helpful to control the quality of pork.

Gordonia prachuapensis sp. nov. and Gordonia sesuvii sp. nov., two novel actinobacteria isolated from mangrove sediments and leaves of halophyte Sesuvium portulacastrum in Thailand.

A polyphasic approach was used to characterize two novel actinobacterial strains, designated PKS22-38T and LSe1-13T, which were isolated from mangrove soils and leaves of halophyte Sesuvium portulacastrum (L.), respectively. Phylogenetic analyses based on 16S rRNA gene sequences showed that they belonged to the genus Gordonia and were most closely related to three validly published species with similarities ranging from 98.6 to 98.1 %. The genomic DNA G+C contents of strains PKS22-38T and LSe1-13T were 67.3 and 67.2 mol%, respectively. The average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) values between the two strains were 93.3 and 54.9 %, respectively, revealing that they are independent species. Meanwhile, the ANI and dDDH values between the two novel strains and closely related type strains were below 80.5 and 24.0 %, respectively. Strains PKS22-38T and LSe1-13T contained C16 : 0, C18 : 1 ω9c and C18 : 0 10-methyl (TBSA) as the major fatty acids and diphosphatidylglycerol, phosphatidylethanolamine and phosphatidylinositol as the main phospholipids. The predominant menaquinone was MK-9(H2). Based on phenotypic, chemotaxonomic, phylogenetic and genomic data, strains PKS22-38T and LSe1-13T are considered to represent two novel species within the genus Gordonia, for which the names Gordonia prachuapensis sp. nov. and Gordonia sesuvii sp. nov. are proposed, with strain PKS22-38T (=TBRC 17540T=NBRC 116256T) and strain LSe1-13T (=TBRC 17706T=NBRC 116396T) as the type strains, respectively.

Different lateral packing stress in acyl chains alters KcsA orientation and structure in lipid membranes

The molecular structures of the various intrinsic lipids in membranes regulate lipid-protein interactions. These different lipid structures with unique volumes produce different lipid molecular packing stresses/lateral stresses in lipid membranes. Most studies examining lipid packing effects have used phosphatidylcholine and phosphatidylethanolamine (PE), which are the main phospholipids of eukaryotic cell membranes. In contrast, Gram-negative or Gram-positive bacterial membranes are composed primarily of phosphatidylglycerol (PG) and PE, and the physical and thermodynamic properties of each acyl chain in PG at the molecular level remain unresolved. In this study, we used 1-palmitoyl-2-oleoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (POPG, 16:0–18:1 PG) and 1-palmitoyl-2-arachidonoyl-sn-glycero-3-phospho-(1′-rac-glycerol) (PAPG, 16:0–20:4 PG) to prepare lipid bilayers (liposome) with the rod-type fluorescence probe DPH. We measured the lipid packing conditions by determining the rotational freedom of DPH in POPG or PAPG bilayers. Furthermore, we investigated the effect of different monoacyl chains on a K+ channel (KcsA) structure when embedded in POPG or PAPG membranes. The results revealed that differences in the number of double bonds and carbon chain length in the monoacyl chain at sn-2 affected the physicochemical properties of the membrane and the structure and orientation of KcsA.

Essentiality of dietary cholesterol and its interactions with phospholipid in juvenile slipper lobster (Thenus australiensis)

This study was conducted to verify the essentiality of dietary cholesterol for early juvenile slipper lobster, Thenus australiensis (initial weight 4.50 ± 0.72 g, mean ± SD, CV = 0.16), and to explore the potential for interactions between dietary cholesterol and phospholipid. An 8-week experiment was conducted using six experimental feeds containing three supplemental cholesterol concentrations (0, 0.2 and 0.4% dry matter) at two supplemental phospholipid concentrations (0% and 1.0% dry matter). Dietary cholesterol concentrations of ≥ 0.2% resulted in up to threefold greater weight gain compared to 0% dietary cholesterol, but without any significant main or interactive dietary phospholipid effect. An interaction was observed for lobster survival with lowest survival (46%) recorded for combined 0% cholesterol and 0% phospholipid compared to every other treatment (71–100%). However, all surviving lobsters at 0% dietary cholesterol, regardless of dietary phospholipid level, were in poor nutritional condition. Apparent feed intake (AFI) was significantly higher at dietary cholesterol ≥ 0.2% but was lower for each corresponding dietary cholesterol level at 1% dietary phospholipid. This implied that the feed conversion ratio was improved with supplemental phospholipid. In conclusion, this study confirms the essential nature of dietary cholesterol and that dietary phospholipid can provide additional benefits.

Streptomyces profundus sp. nov., a novel marine actinobacterium isolated from deep-sea sediment of Madeira Archipelago, Portugal.

A novel strain, MA3_2.13T, was isolated from deep-sea sediment of Madeira Archipelago, Portugal, and characterized using a polyphasic approach. This strain produced dark brown soluble pigments, bronwish black substrate mycelia and an aerial mycelium with yellowish white spores, when grown on GYM 50SW agar. The main respiratory quinones were MK-10(H4), MK-10(H6) and MK-10(H8). Diphosphatidylglycerol, phosphatidylethanolamine, three unidentified phospholipids and two glycophospholipids were identified as the main phospholipids. The major cellular fatty acids were iso-C16 : 1, iso-C16 : 0, anteiso-C17 : 1 and anteiso-C17 : 0. Phylogenetic analyses based on 16S rRNA gene showed that strain MA3_2.13T is a member of the genus Streptomyces and was most closely related to Streptomyces triticirhizae NEAU-YY642T (NR_180032.1; 16S rRNA gene similarity 97.9 %), Streptomyces sedi YIM 65188T (NR_044582.1; 16S rRNA gene similarity 97.4 %), Streptomyces mimosae 3MP-10T (NR_170412.1; 16S rRNA gene similarity 97.3 %) and Streptomyces zhaozhouensis NEAU-LZS-5T (NR_133874.1; 16S rRNA gene similarity 97.0 %). Genome pairwise comparisons with closest related type strains retrieved values below the threshold for species delineation suggesting that strain MA3_2.13T represents a new branch within the genus Streptomyces. Based on these results, strain MA3_2.13T (=DSM 115980T=LMG 33094T) is proposed as the type strain of a novel species of the genus Streptomyces, for which the name Streptomyces profundus sp. nov. is proposed.

Impact of lipid matrix composition on the activity of membranotropic enzymes galactonolactone oxidase from Trypanosoma cruzi and L-galactono-1,4-lactone dehydrogenase from &lt;i&gt;Arabidopsis thaliana&lt;/i&gt; in the system of reverse micelles

The study of many membrane enzymes in an aqueous medium is difficult due to the loss of their catalytic activity, which makes it necessary to use membrane-like systems, such as reverse micelles of surfactants in nonpolar organic solvents. However, it should be taken into account that micelles are a simplified model of natural membranes, since membranes contain many different components, a significant part of which are phospholipids. In this work, we studied the impact of the main phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), on the activity of membrane enzymes using galactonolactone oxidase from Trypanosoma cruzi (TcGAL) and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana (AtGALDH) as an examples. Effect of the structure (and charge) of the micelle-forming surfactant itself on the activity of both enzymes has been studied using an anionic surfactant (AOT), a neutral surfactant (Bridge-96), and a mixture of cationic and anionic surfactants (CTAB and AOT) as an examples. The pronounced effect of addition of PC and PE lipids on the activity of AtGALDH and TcGAL has been detected, which manifests as increase in catalytic activity and significant change in the activity profile. This can be explained by formation of the tetrameric form of enzymes and/or protein-lipid complexes. By varying composition and structure of the micelle-forming surfactants (AOT, CTAB, and Brijdge-96 and their combinations) it has been possible to change catalytic properties of the enzyme due to effect of the surfactant on the micelle size, lipid mobility, charge, and rigidity of the matrix itself.

Impact of Lipid Matrix Composition on Activity of Membranotropic Enzymes Galactonolactone Oxidase from Trypanosoma cruzi and L-Galactono-1,4-Lactone Dehydrogenase from Arabidopsis thaliana in the System of Reverse Micelles.

The study of many membrane enzymes in an aqueous medium is difficult due to the loss of their catalytic activity, which makes it necessary to use membrane-like systems, such as reverse micelles of surfactants in nonpolar organic solvents. However, it should be taken into account that the micelles are a simplified model of natural membranes, since membranes contain many different components, a significant part of which are phospholipids. In this work, we studied impact of the main phospholipids, phosphatidylcholine (PC) and phosphatidylethanolamine (PE), on activity of the membrane enzymes using galactonolactone oxidase from Trypanosoma cruzi (TcGAL) and L-galactono-1,4-lactone dehydrogenase from Arabidopsis thaliana (AtGALDH) as examples. Effect of the structure (and charge) of the micelle-forming surfactant itself on the activity of both enzymes has been studied using an anionic surfactant (AOT), a neutral surfactant (Brij-96), and a mixture of cationic and anionic surfactants (CTAB and AOT) as examples. The pronounced effect of addition of PC and PE lipids on the activity of AtGALDH and TcGAL has been detected, which manifests as increase in catalytic activity and significant change in the activity profile. This can be explained by formation of the tetrameric form of enzymes and/or protein-lipid complexes. By varying composition and structure of the micelle-forming surfactants (AOT, CTAB, and Brij-96) it has been possible to change catalytic properties of the enzyme due to effect of the surfactant on the micelle size, lipid mobility, charge, and rigidity of the matrix itself.

Effect of phospholipids on the oxidative reactivity and microstructure of soot particles from Jatropha biodiesel combustion

Excessive phosphorus content can aggravate the formation and emission of particulate matter (PM) during biodiesel combustion, which can lead to the performance degradation of automobile exhaust catalytic converters and make it difficult to control pollutant emissions. However, the influential mechanism of phosphorus in biodiesel on PM formation is not clear yet. Therefore, thermogravimetric analysis (TGA), X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, high-resolution transmission electron microscopy (HRTEM), and Raman spectroscopy are used to study the formation, oxidation characteristics, and nanostructures of soot particles produced from Jatropha biodiesel (JB100) combustion under different phospholipid (PE:phosphatidylethanolamine, main phospholipid type in JB100) contents. The results show that with increasing PE content in JB100, the amount of soot particles first increases and then decreases. When the PE content is 400 ppm, the amount of soot particles is the largest, almost 13.40% higher than that produced from neat JB100. Further, the activation energy (AE) of soot oxidation first increases and then decreases with increasing PE content. The apparent AE is the largest (131.40 kJ/mol) at 400 ppm. Furthermore, when the PE content is 400 ppm, the strength of oxygen-containing functional groups in the soot particles is the weakest, and the ratio of nanocrystal height to polycyclic aromatic hydrocarbons (PAHs) interlayer spacing (Lc/d002) (4.396), the average lattice spacing of PAHs (0.367 nm), and the ratio of D1 and G peaks integral intensity (ID1/IG) (2.566) are minimum. This verifies that the PE content in JB100 can affect the strength of active oxygen-containing functional groups and the size and structure of PAHs in the soot particles and that the oxidative reactivity of soot particles is lowest at 400 ppm.

Phospholipid dependency of membrane protein insertion by the Sec translocon

Membrane protein insertion into and translocation across the bacterial cytoplasmic membrane are essential processes facilitated by the Sec translocon. Membrane insertion occurs co-translationally whereby the ribosome nascent chain is targeted to the translocon via signal recognition particle and its receptor FtsY. The phospholipid dependence of membrane protein insertion has remained mostly unknown. Here we assessed in vitro the dependence of the SecA independent insertion of the mannitol permease MtlA into the membrane on the main phospholipid species present in Escherichia coli. We observed that insertion depends on the presence of phosphatidylglycerol and is due to the anionic nature of the polar headgroup, while insertion is stimulated by the zwitterionic phosphatidylethanolamine. We found an optimal insertion efficiency at about 30 mol% DOPG and 50 mol% DOPE which approaches the bulk membrane phospholipid composition of E. coli.

Effect of different degumming processes on the retention of bioactive components, acylglycerol and phospholipid composition of rapeseed oil

Rapeseed oil is enriched with nutrients, and its quality is significantly influenced by different processes. However, few studies have systematically investigated the correlation between different degumming processes and rapeseed oil quality. In this study, five degumming processes were applied to crude rapeseed oil, and enzymatic degumming processes were optimized. Furthermore, the effect of five degumming processes on the retention of bioactive components, acylglycerol and phospholipid profiles in rapeseed oil was investigated. Acid degumming caused more loss of bioactive components, while phospholipase A1 combined with phospholipase C degumming provided better retention of bioactive components. OOO (C18:1/C18:1/C18:1), OOL (C18:1/C18:1/C18:2) and OLL (C18:1/C18:2/C18:2) were the most abundant acylglycerols in crude rapeseed and degummed oil from different degumming processes. This result indicated no significant difference in the effect of the different degumming processes on the acylglycerol profile. The phospholipid composition of degummed oils varied with different degumming processes. Phosphatidylcholine (PC) and phosphatidylethanolamine (PE) were the main phospholipids in water and acid degummed oil, while phosphatidic acid (PA) and phosphatidylglycerol (PG) were the predominant phospholipids in enzymatic degummed oil. These results may provide information to underpin the relationship between rapeseed oil quality and different degumming processes.

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.

Molecular regulation of lipid metabolism in Suaeda salsa

Suaeda salsa is remarkable for its high oil content and abundant unsaturated fatty acids. In this study, the regulatory networks on fatty acid and lipid metabolism were constructed by combining the de novo transcriptome and lipidome data. Differentially expressed genes (DEGs) associated with lipids biosynthesis pathways were identified in the S. salsa transcriptome. DEGs involved in fatty acid and glycerolipids were generally up-regulated in leaf tissues. DEGs for TAG assembly were enriched in developing seeds, while DEGs in phospholipid metabolic pathways were enriched in root tissues. Polar lipids were extracted from S. salsa tissues and analyzed by lipidomics. The proportion of galactolipid MGDG was the highest in S. salsa leaves. The molar percentage of PG was high in the developing seeds, and the other main phospholipids had higher molar percentage in roots of S. salsa. The predominant C36:6 molecular species indicates that S. salsa is a typical 18:3 plant. The combined transcriptomic and lipidomic data revealed that different tissues of S. salsa were featured with DEGs associated with specific lipid metabolic pathways, therefore, represented unique lipid profiles. This study will be helpful on understanding lipid metabolism pathway and exploring the key genes involved in lipid synthesis in S. salsa.

Membrane lipid composition of Carnobacterium maltaromaticum CNCM I-3298, a highly cryoresistant lactic bacterium

The growing consumption of fermented products has led to an increasing demand for lactic acid bacteria (LAB), especially for LAB tolerant to freezing/thawing conditions. Carnobacterium maltaromaticum is a psychrotrophic and freeze-thawing resistant lactic acid bacterium. The membrane is the primary site of damage during the cryo-preservation process and requires modulation to improve cryoresistance. However, knowledge about the membrane structure of this LAB genus is limited. We presented here the first study of the membrane lipid composition of C. maltaromaticum CNCM I-3298 including the polar heads and the fatty acid compositions of each lipid family (neutral lipids, glycolipids, phospholipids). The strain CNCM I-3298 is principally composed of glycolipids (32%) and phospholipids (55%). About 95% of glycolipids are dihexaosyldiglycerides while less than 5% are monohexaosyldiglycerides. The disaccharide chain of dihexaosyldiglycerides is composed of α-Gal(1−2)-α-Glc chain, evidenced for the first time in a LAB strain other than Lactobacillus strains. Phosphatidylglycerol is the main phospholipid (94%). All polar lipids are exceptionally rich in C18:1 (from 70% to 80%). Regarding the fatty acid composition, C. maltaromaticum CNCM I-3298 is an atypical bacterium within the genus Carnobacterium due to its high C18:1 proportion but resemble the other Carnobacterium strains as they mostly do not contain cyclic fatty acids.

Phosphatidylcholine and cholesterol-loaded-cyclodextrins can replace egg yolk in the cryopreservation of equine spermatozoa

In the horse breeding industry, cryopreservation of spermatozoa has become an integral aspect of modern-day protocols. To avoid sperm damage during the freezing process, freezing media containing egg yolk are used. Recently, urgency to find an alternative to egg yolk has been increased due to the prevalence of Avian Influenza Virus (AIV). In the UK, the World Organization for Animal Health reports that between July and December 2022, an AIV outbreak led to the death of 4.62 million birds (56.73 million globally), with substantial consequences for agriculture, environment and egg availability (WAHIS. 2023; https://wahis.woah.org/#/dashboard/qd-dashboard: Accessed: 12 January 2023). Recent research has also called into question the biosafety of egg yolk, with RNA from highly pathogenic and low pathogenic AIV found on and in eggs (Stephens.et.al. Avian Diseases. 2020; 64:143-148). The cryoprotectant potential of phosphatidylcholine, the main phospholipid in egg yolk, has been investigated in diluents used for cryopreservation of human spermatozoa with some success (Sicchieri.et.al. Translational Andrology and Urology. 2021; 10:397-407). The chemically defined origin and increased biosafety make phosphatidylcholine a desirable alternative to egg yolk for use in cryopreservation. Ejaculates from four horses (n=4) were frozen using four different freezing extenders: a reference medium containing egg yolk and 3% dimethylformamide (control) and media without egg yolk supplemented with 1.5mg/ml2-hydroxypropyl-β-cyclodextrin cholesterol complex, 3% dimethylformamide and either 2% (P1), 4% (P2) or 6% phosphatidylcholine (P3). Samples were diluted and centrifuged on a density gradient medium (1000xg’ for 20 minutes). The cell band was aspirated and resuspended (200 × 10⁶ cells/ml) with allotted treatment extender. Samples were packed into 0.25ml straws, cooled to 5˚C for 25 minutes, then frozen using a programmable freezing unit (IceCube14s, Minitube, Germany). Temperature of the straws was reduced from 4 ˚C to -143˚C in 9 minutes, after which they were plunged directly into liquid nitrogen (-196˚C). Viability was assessed using NucleoCounter® NC-100™. Total motility analyses were performed with computer assisted semen analysis (Hamilton Thorne, USA). No difference in post-thaw viability was found between any of the media tested (P>0.05). No difference in total motility was found between the control (36.75±1.93σM), P1 (29.25±3.82σM) or P2 media (19.5±6.35σM) (P>0.05). However, post-thaw total motility of sperm cryopreserved in P3 media (16±6.01σM) was lower than the control (P<0.05). Media supplemented with 2-4% phosphatidylcholine and 1.5mg/ml cholesterol was effective in limiting loss of total motility and membrane integrity of equine spermatozoa, establishing the need for further breeding trials into the use of phospholipids for egg yolk lipid replacement to improve biosafety. The authors wish to recognize the support of Tullis Matson and Stallion AI Services Ltd in this study.

New Meloxicam Derivatives-Synthesis and Interaction with Phospholipid Bilayers Measured by Differential Scanning Calorimetry and Fluorescence Spectroscopy.

The purpose of the present paper was to assess the ability of five newly designed and synthesized meloxicam analogues to interact with phospholipid bilayers. Calorimetric and fluorescence spectroscopic measurements revealed that, depending on the details of the chemical structure, the studied compounds penetrated bilayers and affected mainly their polar/apolar regions, closer to the surface of the model membrane. The influence of meloxicam analogues on the thermotropic properties of DPPC bilayers was clearly visible because these compounds reduced the temperature and cooperativity of the main phospholipid phase transition. Additionally, the studied compounds quenched the fluorescence of prodan to a higher extent than laurdan, what pointed to a more pronounced interaction with membrane segments close to its surface. We presume that a more pronounced intercalation of the studied compounds into the phospholipid bilayer may be related to the presence of the molecule of a two-carbon aliphatic linker with a carbonyl group and fluorine substituent/trifluoromethyl group (compounds PR25 and PR49) or the three-carbon linker together with the trifluoromethyl group (PR50). Moreover, computational investigations of the ADMET properties have shown that the new meloxicam analogues are characterized by beneficial expected physicochemical parameters, so we may presume that they will have a good bioavailability after an oral administration.

Impact of dietary n-3 polyunsaturated fatty acid intake during the perinatal and post-weaning periods on the phospholipid and ganglioside composition of olfactory tissues.

The olfactory mucosa (OM) and olfactory bulb (OB) are neuronal tissues that contribute to the early processing of olfactory information. They contain significant amounts of n-3 and n-6 polyunsaturated fatty acids (PUFAs), which are crucial for neuronal tissue development. In this study, we evaluated the impact of feeding mice diets that are either deficient in α-linolenic acid (ALA) or supplemented with n-3 long-chain PUFAs from gestation to adolescence on the phospholipid and ganglioside composition of these tissues. Both diets modified the levels of some phospholipid classes, notably the phosphatidylserine and phosphatidylethanolamine levels. In addition, the low-ALA diet enriched n-6 PUFAs in the main phospholipid classes of both tissues, while the diet supplemented with n-3 PUFAs enhanced the n-3 PUFA-containing phospholipid species level, mainly in OM. The diets also modulated the levels and profiles of several ganglioside classes in OM and OB. These modifications may have repercussions on the olfactory sensitivity.

Changes of lipid composition from culture fluid during the production of antibiotic salinomycin

A major step in the biotechnological process of production of antibiotic salinomycin is fermentation, which has the greatest impact on the quality of the final product. Vegetable oils (rapeseed or soybean) are used as nutrient medium during fermentation, with some of the lipids embedded in the final product. Data on their effect on product quality is missing, which is why a study of the changes in the composition of lipids in cultural fluid during the fermentation process was conducted. The composition of the residual lipids isolated from three samples of the culture fluid during fermentation (213, 405 and 490 hours), was investigated before drying the final product. The lipid content of the samples was 6.3%, 3.5% and 6.2%. The main trend is an increase in the amount of saturated fatty acids at the expense of a decrease in unsaturated acids. The amount of tocopherols during the fermentation process increased as well as γ-tocopherol, while the amount of α-tocopherol decreased. The content of carotenoids decreased twice during fermentation. Phosphatidylcholine and phosphatidylethanolamine were identified as major polar lipid components. The main phospholipid classes contain mainly palmitic, stearic and oleic acids. Significant changes in general lipid composition were observed during the biosynthesis process.