In this study, we investigated the laboratory-scale preparation and characteristics of ethanolamine plasmalogen from marine invertebrates. The preparation method consists of fractionation by acetone and ether treatment, and separation using column chromatography with silica gel and different eluents. Plasmalogen fractions (Pls fraction) were obtained from the viscera of the ascidian Halocynthia roretzi, and the prominent fatty acids were present as 20:5 (33.0%) and 22:6 (29.6%) n-3 polyunsaturated fatty acids (PUFA). The plasmalogen purity was 40%, and the alkenyl chains consisted of 18:0 (86.1%), 16:0 (5.9%) and 18:1 (4.9%). Precursor ion scanning in negative and positive ion modes using liquid chromatography tandem mass spectrometry (LC-MS/MS) enabled the profiling of phosphatidylethanolamine (PE) molecular species in ascidian viscera. Following LC-MS/MS with multiple reaction monitoring (MRM), the prominent plasmalogen species were found to be 18:0p/20:5 (30.4%) and 18:0p/22:6 (24.6%) (p at sn-1 position indicates alkenyl linkage). In conclusion, this preparative procedure using ascidian viscera as a source achieved 40% pure plasmalogen that was rich in n-3 PUFA. In addition, an LC-MS/MS assay enabled rapid analysis of plasmalogen species with selectivity and sensitivity. The present results will contribute to the understanding of dietary plasmalogen absorption and metabolism.

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Increasing evidence of phospholipid peroxidation in the pathophysiology of various diseases demonstrates the need for pure phosphatidylcholine hydroperoxide (PCOOH) reference as a standard for quantification, and for biological studies in this field. Our previous study showed the usability of reaction between hydroperoxide and vinyl ether for preparation of PCOOH. However, the reaction has sometimes provided brown byproducts. Here, we report a method to improve reaction conditions, and demonstrate the production of 30 mg of PCOOH (a pure mixture of 13- and 9-hydroperoxyoctadecadienoyl PCOOH isomers) from 100 mg of phosphatidylcholine without byproduct formation. The resultant PCOOH will be useful as a standard for quantification studies, as well as for the evaluation of PCOOH pathogenicity.

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Hypercholesterolemia is a major cause of coronary heart disease. Erythrocyte membrane is affected during hypercholesterolemia. The effect of EPA-DHA rich sterol ester and ALA rich sterol ester on erythrocyte membrane composition, osmotic fragility in normal and hypercholesterolemic rats and changes in antioxidant status of erythrocyte membrane were studied. Erythrocyte membrane composition, osmotic fragility of the membrane and antioxidant enzyme activities was analyzed. Osmotic fragility data suggested that the erythrocyte membrane of hypercholesterolemia was relatively more fragile than that of the normal rats’ membrane which could be reversed with the addition of sterol esters in the diet. The increased plasma cholesterol in hypercholesterolemic rats could also be lowered by the sterol ester administration. There was also marked changes in the antioxidant enzyme activities of the erythrocyte membrane. Antioxidant enzyme levels decreased in the membrane of the hypercholesterolemic subjects were increased with the treatment of the sterol esters. The antioxidative activity of ALA rich sterol ester was better in comparison to EPA-DHA rich sterol ester. In conclusion, rat erythrocytes appear to be deformed and became more fragile in cholesterol rich blood. This deformity and fragility was partially reversed by sterol esters by virtue of their ability to lower the extent of hypercholesterolemia.

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Triacylglycerols (TAG) of two different refined fish oils from sardine and a mixture of tuna and sardine oil were separated by reverse phase high performance liquid chromatography (RP-HPLC) with a binary solvent gradient of acetone/acetonitrile. Different fractions were observed in the chromatogram and TAG species were tentatively identified by subsequent analysis of the fatty acid (FA) profile in each fraction by capillary Gas Chromatography (GC). Peak identities were assigned on the basis of a multiple linear regression analysis by using factors such as carbon number, number of double bonds, number of monounsaturated fatty acids (MUFA) and number of polyunsaturated fatty acids (PUFA) in the molecule as predictors for TAG retention time. A successful correlation was obtained between retention times and the equivalent carbon number (ECN) of triacylglycerols. Regiospecific analysis of fatty acids in the TAG has been conducted by ethanolysis of the fish oil by using an immobilized lipase. The subsequent separation of 2-monoacylglycerol (2-MAG) by TLC (thin layer chromatography) analysis showed that ethanolysis system is effective for analysis of FA composition at the 2-position in oils containing PUFA. Principal components analysis (PCA) has been also applied to establish correlations between the different fatty acids in the TAG.

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The fatty acid compositions of the total lipids of three edible deep-sea fishes, Diaphus watasei, Diaphus suborbitalis, and Benthosema pterotum, were compared with those of a highly migratory fish, Katsuwonus pelamis, to clarify their lipid characteristics and nutritional value as seafood. The mean lipid contents in the three myctophids were markedly higher than was that of K. pelamis. All three myctophids had medium levels of 20:5n-3 (icosapentaenoic acid, EPA) and 22:6n-3 (docosahexaenoic acid, DHA) in their lipids, similar to those in surface pelagic fishes. The actual EPA and DHA amounts of the three myctophid fishes were higher than were those of K. pelamis. Therefore, the nutritional values of the myctophids as source for EPA and DHA are better than that of K. pelamis, and this finding may introduce a new resource of healthy marine food from these under-utilized deep-sea fish species.

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The lipid and fatty acid compositions of the muscle and liver of five Epinephelinae fishes (Epinephelus fasciatus, Epinephelus retouti, Cephalopholis aurantia, Cephalopholis miniatus, and Variola louti) in the coral reef were investigated. The major polyunsaturated fatty acid (PUFA) in the Epinephelinae fish triacylglycerols was 22:6n-3 (docosahexaenoic acid; DHA), which was similar to high levels of DHA in the depot triacylglycerols of highly migratory fishes. In the phospholipids of all specimens, unusually high levels of 20:4n-6 (arachidonic acid; ARA), 22:5n-6 (docosapentaenoic acid; n-6 DPA), and 20:5n-3 (icosapentaenoic acid; EPA) were found with markedly high levels of DHA. Noticeable levels of n-6 long-chain PUFA, such as ARA and n-6 DPA, were found in the muscle and liver polar lipids and suggested a typical profile of the fatty acid composition of coral demersal fishes. The five Epinephelinae fishes were healthful marine foods containing markedly high levels of DHA with noticeable levels of various n-3 and n-6 PUFA.

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A study was conducted on olive oils extracted from olives collected in South West Calabria (Southern Italy) over three harvest years 2010-2011-2012. Three autochthonous cultivars were considered: Cassanese, Ottobratica and Sinopolese and seven allochtonous cultivars: Coratina, Itrana, Leccino, Nocellara Messinese, Nociara, Pendolino and Picholine. Thin Layer Chromatography – Gas Chromatograph (TLC-GC) technique permitted the separation and analysis of the fatty alcohol compounds. A general decline in fatty alcohol content was found during the three months of sampling, most evident in hexacosanol. Pendolino showed the greatest decline. A less evident decrease was measured in the odd chained fatty alcohols, mainly in heptacosanol. Both harvest date and cultivar significantly influenced the fatty alcohol content. This is the first report about the fatty alcohol variation during ripening in olive oil produced in South West Calabria (Southern Italy).

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The use of vegetable oil-based ester as a base fluid in synthetic drilling fluid has become a trend in drilling operations due to its environmental advantages. The transesterification reaction of palm oil methyl ester (POME) with 2-ethylhexanol (2EH) produced 98% of palm oil-based ethylhexyl ester in less than 30 minutes. Since the transesterification reaction of POME with 2EH is a reversible reaction, its kinetics was studied in the presence of excess EH and under vacuum. The POME-to-EH molar ratio and vacuum pressure were held constant at 1:2 and 1.5 mbar respectively and the effects of temperature (70 to 110°C) were investigated. Using excess of EH and continual withdrawal of methanol via vacuum promoted the reaction to complete in less than 10 minutes. The rate constant of the reaction (k) obtained from the kinetics study was in the range of 0.44 to 0.66 s^–1 and the activation energy was 15.6 kJ.mol^–1. The preliminary investigations on the lubrication properties of drilling mud formulated with palm oil-based 2EH ester indicated that the base oil has a great potential to substitute the synthetic ester-based oil for drilling fluid. Its high kinematic viscosity provides better lubrication to the drilling fluid compared to other ester-based oils. The pour point (–15°C) and flash point (204°C) values are superior for the drilling fluid formulation. The plastic viscosity, HPHT filtrate loss and emulsion stability of the drilling fluid had given acceptable values, while gel strength and yield point could be improved by blending it with proper additives.

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Gold/titania nanocomposites with a core–shell structure were prepared by sol–gel reaction of titanium tetrabutoxide (TTBO) with gold nanoparticles, core-stabilized with cetyltrimethylammonium bromide (CTAB), using a ternary mixture of alcohol/acetonitrile/water as solvent. TEM characterization of the resulting constructs revealed spherical nanocomposites, each containing a single gold core. The mean diameter of the gold cores was 13 nm, while the thicknesses of titania shells were readily tuned in the range 4–30 nm by varying the alkyl chain length of the alcohol. In addition, the gold nanoparticles exhibited a deep red color, with an intense extinction peak at 527 nm, owing to their surface plasmon resonance (SPR) properties. When the Au nanoparticles were coated with a titania shell, their color changed to purple and the SPR peak shifted to a higher wavelength of 537 nm. Furthermore, the core–shell nanocomposites were found to display photocatalytic activity for the oxidation of 2-propanol under illumination by visible light (λ=500–560 nm).

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The chemical composition of essential oil, antioxidant and pancreatic lipase inhibitory activities of various solvent extracts obtained from pomegranate peelTunisian cultivar was evaluated. Gas chromatography/mass spectrometry was used to determine the composition of the PP essential oil. Nine-teen components were identified and the main compounds were the camphor (60.32%) and the benzaldehyde (20.98%). The phenolic and flavonoids content varied from 0 to 290.10 mg Gallic acid equivalent and from 5.2 to 20.43 mg catechin equivalent/g dried extract. The antioxidant activity of various solvent extracts from pomegranate peel was also investigated using various in vitro assays as the 1,1-diphenyl-2-picrylhydrazyl (DPPH) radical method, β-carotene bleaching and reducing power assays.Methanol and ethanol extracts showed the most potent antioxidant activity in all assays tested followed by water and acetone extracts. The inhibitory effect of the pomegranate peelextracts on porcine pancreatic lipase was evaluated and the results showed that ethanol and methanol extracts markedly reduced lipase activity. Generally, the highestlipase activity inhibitory (100%) was observed at a concentration of 1 mg/ml after 30 min of incubation. LC-MS analysis of ethanol extract showed the presence of four components which are cholorogenic acid, mannogalloylhexoside, gallic acid and ellagic acid. Our findings demonstrate that the ethanol extract from pomegranate peel might be a good candidate for furtherinvestigations of new bioactive substances.

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An increase in serum plasmalogens (1-O-alk-1-enyl-2-acyl glycerophospholipids), which are endogenous anti-oxidative phospholipids, can potentially prevent age-related diseases such as atherosclerosis and metabolic syndrome (MetS). Very long chain fatty acids (VLCFAs) in plasma may supply the materials for plasmalogen biosynthesis through peroxisomal beta-oxidation. On the other hand, elevated levels of saturated and monounsaturated VLCFAs in plasma appear to be associated with decreased peroxisomal function, and are a symptom of age-related diseases. To reconcile these contradictory findings, we attempted to investigate the relationship between the serum levels of saturated and monounsaturated VLCFAs, clinical and biochemical parameters, and serum levels of plasmalogens in subjects with MetS (n = 117), who were asymptomatic Japanese males over 40 years of age. Fatty acids in serum lipids were quantified using gas chromatography/mass spectrometry (GC/MS). Serum plasmalogen levels were determined by liquid chromatography using radioactive iodine (¹²⁵I-HPLC), and the molecular composition of serum plasmalogens was analyzed by liquid chromatography-tandem mass spectrometry (LC/MS/MS). We found that MetS subjects showed a significant reduction in the proportion of specific saturated and monounsaturated VLCFAs such as behenic acid (C22:0), lignoceric acid (C24:0), and nervonic acid (C24:1) in serum lipids compared to non-MetS subjects. These VLCFAs were positively associated with serum levels of high density lipoprotein cholesterol (HDL-C) as well as plasmalogen-related parameters, and inversely with serum levels of triglyceride (TG) and small dense low density lipoprotein cholesterol (sdLDL-C). In conclusion, the proportion of nervonic acid in serum lipids is associated with serum levels of plasmalogens and with MetS, and probably reflects the peroxisomal dysfunction and enhancement of endoplasmic reticulum (ER) stress seen in common age-related diseases.

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A simple and convenient method has been developed for the synthesis of esters from the corresponding carboxylic acids and alkyl halides by using a stoichiometric amount of tetrabutylammonium fluoride (Bu₄NF) as the base. The reaction of carboxylic acids and a Bu₄NF/THF solution in DMF or THF as the solvent generates carboxylate ions in situ. The carboxylate ions thus generated and accumulated are highly reactive. They are then allowed to react with alkyl halides as the electrophiles, and afford the corresponding esters in moderate to good yields. The reaction without Bu₄NF does not afford any product; therefore, Bu₄NF seems to play an important role as the base in these reactions. A bulky countercation such as the tetrabutylammonium cation seems to increase the reactivity of the carboxylate ions in the solution phase.

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