著者

Toshiharu Nagai Tetsuaki Kinoshita Erika Kasamatsu Kazuaki Yoshinaga Hoyo Mizobe Akihiko Yoshida Yutaka Itabashi Naohiro Gotoh

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

pp.ess19122, (Released:2019-09-11)

被引用文献数

17

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The rapid and simultaneous separation of triacylglycerol (TAG) enantiomers and positional isomers was achieved using chiral high performance liquid chromatography (HPLC). TAGs composed of two fatty acids, which were both saturated (P: palmitic acid or S: stearic acid) and unsaturated (O: oleic acid or L: linoleic acid; e.g., sn-PPO/sn-OPP/sn-POP: 1,2-dipalmitoyl-3-oleoyl-sn-glycerol/1-oleoyl-2,3- dipalmitoyl-sn-glycerol/1,3-dilpalmitoyl-2-oleoylglycerol), were resolved into three peaks using CHIRALPAK IF-3 without recycling on the HPLC system. For example, the mixture of sn-PPO/sn-OPP/sn-POP was resolved in 30 min, although it took 150 min to resolve sn-PPO/sn-OPP using CHIRALCEL ODRH in a previous study using a recycling HPLC system. This novel chiral HPLC method was applicable for the separation of other TAG isomers, including sn-OOP/sn-POO/sn-OPO, sn-PPL/sn-LPP/sn-PLP, sn-LLP/sn-PLL/sn-LPL, sn-SSO/sn-OSS/sn-SOS, sn-OOS/sn-SOO/sn-OSO, sn-SSL/sn-LSS/sn-SLS, and sn-LLS/snSLL/sn-LSL. For TAGs composed of three fatty acids containing both saturated and unsaturated fatty acids, the POL isomers were not sufficiently separated but the PSO and SOL isomers were partially separated into several peaks. Their elution order could be estimated by the fragment ions generated in the ion source of the mass spectrometer. However, TAGs consisting of only saturated or unsaturated fatty acids (e.g., sn-PSP/sn-PPS/sn-SPP and sn-OLO/sn-OOL/sn-LOO) were not separated. This novel chiral HPLC method is especially applicable for the analysis of TAG composition of semi-solid fats such as palm oil.

著者

Koji Nagao Kazusa Nakamitsu Hiroki Ishida Kazuaki Yoshinaga Toshiharu Nagai Hoyo Mizobe Koichi Kojima Teruyoshi Yanagita Fumiaki Beppu Naohiro Gotoh

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

vol.63, no.10, pp.979-985, 2014 (Released:2014-10-01)

参考文献数

29

被引用文献数

22 23

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The effects on lipid metabolism of four different n-3 highly unsaturated fatty acids (n-3HUFA) including eicosapentaenoic acid (EPA, 20:5n-3), docosapentaenoic acid (DPA, 22:5n-3), docosahexaenoic acid (DHA, 22:6n-3), and tetracosahexaenoic acid (THA, 24:6n-3) were compared in the HepG2 cell model. None of the n-3HUFAs affected the viability of the cells. THA exerted the strongest suppression on the synthesis of triacylglycerol and cholesteryl ester (ChE), and the order of the strength of suppression was found to be THA > DHA > DPA > EPA. The mRNA level of fatty acid synthase was suppressed by the n-3HUFAs and the order of the strength of suppression by n-3HUFAs was the same in both triacylglycerol and ChE synthesis. These findings support previous animal test results using EPA, DPA, and DHA. In conclusion, both the number of carbon atoms and double bonds in an n-3HUFA structure has an effect on lipid metabolism in HepG2 cells.

著者

Naohiro Gotoh Satoshi Kagiono Kazuaki Yoshinaga Hoyo Mizobe Toshiharu Nagai Akihiko Yoshida Fumiaki Beppu Koji Nagao

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

vol.67, no.3, pp.273-281, 2018 (Released:2018-03-01)

参考文献数

29

被引用文献数

5 16

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The intake of trans fatty acids (TFAs) in foods changes the ratio of low density lipoprotein (LDL) to high density lipoprotein (HDL) cholesterol in blood, which causes cardiovascular disease. TFAs are formed by trans isomerization of unsaturated fatty acids (UFAs). The most recognized formation mechanisms of TFAs are hydrogenation of liquid oil to form partially hydrogenated oil (PHO,) and biohydrogenation of UFAs to form TFA in ruminants. Heating oil also forms TFAs; however, the mechanism of formation, and the TFA isomers formed have not been well investigated. In this study, the trans isomerization mechanism of unsaturated fatty acid formation by heating was examined using the model compounds oleic acid, trioleate, linoleic acid, and trilinoleate for liquid plant oil. The formation of TFAs was found to be suppressed by the addition of an antioxidant and argon gas. Furthermore, the quantity of formed TFAs correlated with the quantity of formed polymer in trioleate heated with air and oxygen. These results suggest that radical reactions form TFAs from UFAs by heating. Furthermore, trans isomerization by heating oleic acid and linoleic acid did not change the original double bond positions. Therefore, the distribution of TFA isomers formed was very simple. In contrast, the mixtures of TFA isomers formed from PHO and ruminant UFAs are complicated because migration of double bonds occurs during hydrogenation and biohydrogenation. These findings suggest that trans isomerization by heating is executed by a completely different mechanism than in hydrogenation and biohydrogenation.

著者

Naohiro Gotoh Kazuaki Yoshinaga Satoshi Kagiono Yukiko Katoh Yota Mizuno Fumiaki Beppu Toshiharu Nagai Hoyo Mizobe Akihiko Yoshida Koji Nagao

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

vol.68, no.2, pp.193-202, 2019 (Released:2019-02-01)

参考文献数

37

被引用文献数

4 7

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Trans fatty acids (TFA) are considered risk factors for cardiovascular disease. However, detailed information on total content of TFA and TFA isomers and distribution of trans-octadecenoic acid positional isomers in foods consumed in Japan is not available till date. In this study, 250 foods, 169 processed foods and 81 foods derived from ruminant meat or milk, were analyzed. According to the results, most foods contained less than 1.0 g TFA / 100 g food. However, almost all foods containing butter had more than 1.0 g TFA / 100 g food. TFA isomers in foods were classified into two categories, monoene-rich type and polyenerich type. We hypothesized that these differences were attributed to diverse TFA formation mechanisms. Furthermore, we observed that trans-10-18:1 was also the dominant trans-18:1 positional isomer in foods consumed in Japan. These results are valuable for future analysis of the role of TFA in epidemiological studies in Japan.

著者

Fumiaki Beppu Toshiharu Nagai Kazuaki Yoshinaga Hoyo Mizobe Koichi Kojima Naohiro Gotoh

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

vol.62, no.10, pp.789-794, 2013 (Released:2013-10-02)

参考文献数

33

被引用文献数

3 3

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Triacylglycerol (TAG) molecular species were quantified through high-performance liquid chromatography (HPLC) equipped with a nano quantity analyte detector (NQAD). TAG standard compounds, i.e., 1,3-dipalmitoyl-2-oleoylglycerol (β-POP), 1-palmitoyl-2-oleoyl-3-stearoyl-rac-glycerol (β-POS), and 1,3-distearoyl-2-oleoylglycerol (β-SOS), and natural cocoa butter were used for analyses. NQAD gave the first order equation passing through the origin for all TAG standard compounds. TAG molecular species in cocoa butter were quantified using the calibration curves and the obtained values were almost the same as the reported ones of conventional cocoa butter. Furthermore, a recovery test was also carried out and the values were almost 100. Therefore, HPLC-NQAD can be successfully used for the quantification of TAG molecular species in natural fats and oils.

著者

Kazuaki Yoshinaga Fumiaki Beppu Yoshio Yamatani Atsushi Kubo Aya Yoshinaga-Kiriake Toshiharu Nagai Akihiko Yoshida Jota Kanda Naohiro Gotoh

出版者

Japan Oil Chemists' Society

雑誌

Journal of Oleo Science (ISSN:13458957)

巻号頁・発行日

vol.68, no.6, pp.591-598, 2019 (Released:2019-06-06)

参考文献数

30

被引用文献数

5

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Fatty acids in triacylglycerol (TAG) are catabolized after digestion. However, the catabolic rates of several fatty acids bound to the α (sn-1, 3) or β (sn-2) position of TAG have not been thoroughly compared. In this study, the catabolic rates of 13C-labeled palmitic acid, oleic acid, linoleic acid, α-linolenic acid, eicosapentaenoic acid (EPA), or docosahexaenoic acid (DHA) bound to the α and β position of TAG were compared using isotope ratio mass spectrometry. The catabolic rates of the studied fatty acids were evaluated using the ratio of 13C and 12C in carbon dioxide expired from mice. The results indicated that palmitic acid, oleic acid, or α-linolenic acid bound to the β position was slowly catabolized for a long duration compared to that when bound to the α position. In contrast, EPA bound to the β position was quickly catabolized, and EPA bound to the α position was slowly catabolized for a long time. For linoleic acid or DHA, no difference in the catabolic rates was detected between the binding positions in TAG. Furthermore, EPA and DHA were less catabolized than the other fatty acids. These results indicate that the catabolic rates of fatty acids are influenced by their binding positions in TAG and that this influence on the catabolic rate differed depending on the fatty acid species.