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Edogawa-ku, Japan

Lee J.W.,Osaka University | Nagai T.,Tsukishima Foods Industry Co. | Gotoh N.,Tokyo University of Marine Science and Technology | Fukusaki E.,Osaka University | Bamba T.,Osaka University
Journal of Chromatography B: Analytical Technologies in the Biomedical and Life Sciences | Year: 2014

In this study, supercritical fluid chromatography (SFC) coupled with triple quadrupole mass spectrometry was applied to the profiling of several regioisomeric triacylglycerols (TAGs). SFC conditions (column, flow rate, modifier) were optimized for the effective separation of TAGs. In the column test, a triacontyl (C30) silica gel reversed-phase column was selected to separate TAG regioisomers. Multiple reaction monitoring was used to selectively quantify each TAG. Then, the method was used to perform detailed characterization of a diverse array of TAGs in palm and canola oils. Seventy TAGs (C46:0-C60:2) of these oils were successfully analyzed as a result, and twenty isomeric TAG pairs were separated well. In particular, this method provided the fast and high resolution separation of six regioisomeric TAG pairs (PPLn/PLnP, PPL/PLP, PPO/POP, SPLn/SLnP, SPO/SOP, SSO/SOS-stearic acid (S, 18:0), oleic acid (O, 18:1), linoleic acid (L, 18:2), linolenic acid (Ln, 18:3), palmitic acid (P, 16:0)) in a short time (50. min) as compared to high performance liquid chromatography. We were able to demonstrate the utility of this method for the analysis of regioisomeric TAGs in edible oils. © 2014 Elsevier B.V.

Gotoh N.,Tokyo University of Marine Science and Technology | Wada S.,Tokyo University of Marine Science and Technology | Nagai T.,Tsukishima Foods Industry Co.
Lipid Technology | Year: 2011

A recycle HPLC system equipped with a polysaccharide-based chiral column was used for the enantiomeric separation of asymmetric triacylglycerols (TAGs). When the chiral columns were screened by the resolution of 1,2-dipalmitoyl-3-oleoyl-rac-glycerol separation was achieved only with the cellulose tris- (3,5-dimethylphenylcarbamate) chiral selector. The resolution of other TAG enantiomers was also examined, and 1,2-dioleoyl-3-palmitoyl-rac-glycerol, 1,2-dipalmitoyl-3-linoleoyl-rac-glycerol, 1,2-dipalmitoyl-3-eicosapentaenoyl-rac-glycerol, 1,2-dipalmitoyl-3-docosahexaenoyl-rac-glycerol, and 1,2-docosahexaenoyl-3-palmitoyl-rac-glycerol were resolved into their respective enantiomers. However, neither 1,2-dioleoyl-3-linoleoyl-rac-glycerol, consisting of only unsaturated fatty acids, nor 1,2-dipalmitoyl-3-stearoyl-rac-glycerol, consisting of only saturated fatty acids, was resolved. In addition, 1,2-eicosapentaenoyl-3-palmitoyl-rac-glycerol was not resolved clearly, even in the recycle runs. These results suggest that asymmetric TAGs having both a palmitic acid moiety and an unsaturated fatty acid moiety at the sn-1 or sn-3 positions might be resolved on a cellulose tris- (3,5-dimethylphenylcarbamate) chiral column. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Ito J.,Tohoku University | Nakagawa K.,Tohoku University | Kato S.,Tohoku University | Hirokawa T.,Tohoku University | And 3 more authors.
Journal of Chromatography A | Year: 2015

Increasing evidence suggests that phospholipid peroxidation plays important roles in the pathogenesis of various diseases, such as atherosclerosis. With regard to the biochemical processes that initiate phospholipid peroxidation in vivo, enzymatic conversion of phosphatidylcholine to phosphatidylcholine hydroperoxide (PCOOH) by lipoxygenase (LOX) may play a crucial role. This will become clear if we can analyze PCOOH bearing hydroperoxy fatty acids with S-stereoconfiguration. In this study, we therefore attempted such an analysis. Initially, we used LOX, linoleic acid and Lyso phosphatidylcholine, and synthesized PCOOH bearing 13. S-hydroperoxy-9. Z,11. E-octadecadienoic acid (13(. S)-9. Z,11. E-HPODE). PCOOH bearing racemic 13-9. Z,11. E-HPODE was also prepared. We used liquid chromatography equipped with CHIRALPAK OP (+) (poly (. o-pyridyl diphenylmethacrylate) coated on silica), a UV detector and a quadrupole-time-of-flight mass spectrometer, and achieved diastereomer separation of PCOOH stereoisomers with excellent resolution and peak shape. This is the first study reporting the diastereomer separation of PCOOH. The present method will be beneficial in developing a better understanding of the biochemical processes that initiate oxidative stress (PCOOH formation) in vivo, which may lead to further elucidation of the involvement of PCOOH in the development of diseases. In addition to clinical applications, the present method may also be effective in the evaluation of enzymatic oxidative food deterioration. © 2015 Elsevier B.V.

Okusa K.,GL Sciences Inc. | Iwasaki Y.,GL Sciences Inc. | Kuroda I.,GL Sciences Inc. | Miwa S.,GL Sciences Inc. | And 7 more authors.
Journal of Chromatography A | Year: 2014

A high-density, polymeric C18 stationary phase (Inertsil ODS-P) or a polymeric C30 phase (Inertsil C30) provided improved resolution of the isomeric fatty acids (FAs), FA methyl esters (FAMEs), triacylglycerols (TAGs), and tocopherols with an increase in pressure of 20-70. MPa in reversed-phase HPLC. With respect to isomeric C18 FAMEs with one cis-double bond, ODS-P phase was effective for recognizing the position of a double bond among petroselinic (methyl 6Z-octadecenoate), oleic (methyl 9Z-octadecenoate), and cis-vaccenic (methyl 11Z-octadecenoate), especially at high pressure, but the differentiation between oleic and cis-vaccenic was not achieved by C30 phase regardless of the pressure. A monomeric C18 phase (InertSustain C18) was not effective for recognizing the position of the double bond in monounsaturated FAME, while the separation of cis- and trans-isomers was achieved by any of the stationary phases. The ODS-P and C30 phases provided increased separation for TAGs and β- and γ-tocopherols at high pressure. The transfer of FA, FAME, or TAG molecules from the mobile phase to the ODS-P stationary phase was accompanied by large volume reduction (-30. ~. -90. mL/mol) resulting in a large increase in retention (up to 100% for an increase of 50. MPa) and improved isomer separation at high pressure. For some isomer pairs, the ODS-P and C30 provided the opposite elution order, and in each case higher pressure improved the separation. The two stationary phases showed selectivity for the isomers having rigid structures, but only the ODS-P was effective for differentiating the position of a double bond in monounsaturated FAMEs. The results indicate that the improved isomer separation was provided by the increased dispersion interactions between the solute and the binding site of the stationary phase at high pressure. © 2014 Elsevier B.V.

Gotoh N.,Tokyo University of Marine Science and Technology | Matsumoto Y.,Tokyo University of Marine Science and Technology | Nagai T.,Tsukishima Foods Industry Co. | Mizobe H.,Tsukishima Foods Industry Co. | And 6 more authors.
Food Chemistry | Year: 2011

The distribution of fatty acid species at the (sn-1, 3) position or the (sn-2) position of triacylglycerol (TAG) in natural fats and oils has already been analysed by many researchers and several interesting results have been reported. However, most of these reports only focused on the distribution of fatty acids at the or positions in TAG, and did not take account of the combination of fatty acids in the TAG, i.e., the TAG positional isomers. In this study, the actual ratios of TAG positional isomer pairs, consisting of palmitic acid and highly unsaturated fatty acid (HUFA) such as DHA or EPA, in fish and marine mammals were investigated using a high-performance liquid chromatography/atmospheric pressure chemical ionisation-mass spectrometry (HPLC/APCI-MS) system equipped with tandem jointed non-endcapped polymeric ODS columns. The results show that for combinations of DHA or EPA with two palmitic acids in the TAG of marine mammals, binding was almost all at the α position. In contrast, binding of DHA or EPA was mainly at the β position in fish. The preferred DHA and EPA positions in TAG were the same in the same marine mammal or fish. The binding position tendency of HUFA in TAG positional isomers consisting of two HUFAs and one palmitic acid was the same as that for combinations of one HUFA and two palmitic acids. These results were interpreted as showing that the preferred fatty acid species of sn-glycerol-3-phosphate acyltransferase and 1-acyl-sn-glycerol-3-phosphate acyltransferase in marine mammals are different to those in fish and other animals, or that diacylglycerol acyltransferase in marine mammals favours 1,2-dipalmitoyl-sn-glycerol formed from 1,2-dipalmitoyl-sn-glycerol-3-phosphatidate if HUFA is the reaction substrate. © 2011 Elsevier Ltd. All rights reserved.

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