• Journal of the Korean Society of Food Science and Nutrition
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• v.19 no.3
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• pp.239-247
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• 1990

The oxidation products from the mixture of a-tocopherol (a-Toc) and γ-tocopherol)(γ-Toc) during autoxidation of methyl linoleate were isolated and identified. The sturctures of the oxida-tion products were characterized by UV, IR, 1H and 13CNMR and mass spectrometry 5-[2-(a-tocopherol-5'-yl)ethyl]-a-tocopherylquinone 5-[2-(a-tocopherol-5'-yl)ethyl]-8a-hydroxy-a-tocopherone and O-[8-(5-ethoxymethyl-7-methyltocol) methyl] a-tocopherol were obained from the mixture as the oxidation products derived from γ-Toc However oxidation product composed of both a-ToC and γ-Toc was detected in oxidation products of the misture. These results support the facts that at first oxidation of a-Toc proceeds during autoxidation of lipids and then γ-Toc decomposes after approximate consumption of a-Toc.

• Journal of Nutrition and Health
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• v.39 no.8
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• pp.773-785
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• 2006

Vitamin E in the body system plays an important role in preventing chronic diseases by decreasing the oxidative stress by free-radicals. However, there are not enough researches on analyzing the primary factors affecting vitamin E levels in the blood in Korean adults. Therefore, the purpose of this research was to examine blood tocopherol levels and the primary factors affecting the status. A complete lifestyle survey was performed on 314 Korean adult men and surveyed their smoking, drinking and exercising habits. The average plasma level of ${\alpha}-\;and\;{\gamma}-tocopherol$ showed similar mutual relations with plasma total cholesterol (TC), triglyceride (TG), or low density lipoprotein cholesterol (LDL-C) levels (p<0.001). Plasma ${\alpha}-tocopherol$ level of the subjects did not show any difference as smoking, drinking and exercising habits changed. However, ${\gamma}-tocopherol$ per TG showed much lower figure in smokers than non smokers (p < 0.05). Amongst diet factors, plasma ${\alpha}-tocopherol$ level showed negative correlations with Vitamin E intake, while ${\gamma}-tocopherol$ level showed positive correlations with Vitamin E intake. Erythrocyte superoxide dismutase (SOD) activity and plasma tocopherol showed negative correlations, and catalase activity and plasma ${\alpha}-tocopherol$ showed positive correlationship. The level of cell DNA damage of Iymphocyte and plasma ${\alpha}-\;or\;{\gamma}-tocopherol$ showed negative correlations. As a result of this research, the factors that affect Korean adult men's plasma ${\alpha}-tocopherol$ level are plasma TG, LDL-C and cell DNA damage in Iymphocyte, while the factors that affect ${\gamma}-tocopherol$ level are plasma TG, LDL-C and vitamin E intake based on multiple regression analysis. These findings implies that the level of different types of tocopherol depends on slightly different factors. A further research is needed on the factors involved in the differentiation of the types of tocopherol.

• Preventive Nutrition and Food Science
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• v.9 no.4
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• pp.295-299
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• 2004

Alpha-tocopherol was thermally oxidized and degraded at high temperatures and the resulting products were chromatographically separated and identified by LC-MS. Alpha-tocopherol dissolved in glycerol was heated at 200^{\circ}C for 30 min. The thermal products were separated by hexane extraction and analyzed by HPLC using a reversed phase $\mu$-Bondapak $C_{18}-column$ with two kinds of elution solvents: a mixture of acetonitrile and methanol (3:2), and of acetonitrile, methanol, 2-propanol, chloroform and methylene chloride (3:2:5:0.5:0.5) in a gradient mode. The isolated thermal. products of alpha-tocopherol were more viscous than alpha-tocopherol, and dark brown in color. Major thermal degradation products of alpha-tocopherol were identified by LC-MS, and the structures of thermal products were proposed. Alpha-tocopherol and its thermal degradation products were degraded into fragments, mainly at the non-aromatic parts. The degradation products of alpha-tocopherol. were combined with oxidized product (tocopherylquinone) to make thermal. products through dimerization.

• Journal of Nutrition and Health
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• v.23 no.2
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• pp.81-92
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• 1990

Ten college women were treated with either corn oil(CO< as a source of C18:2, $\omega$6) or fish oil concentrates(FO, as a source of C20:5+C22:6, $\omega$3) with experimental diet for 7 days and then returned to normal home made diet. Kinetic changes of plasma and RBC lipids, tocopherol, MDA levels and hemolysis were observed at day-0, -3, -7, -8, -10, -14 and -21 of experimental periods. Plasma and RBC tocopherol contents were significantly increased at day-3 and -7 by tocopherol tocopherol supplement in dietary oil, but there was no significant difference between CO and FO diet with large dose of tocopherol supplement. After stop experimental regimen at day-7, plasma tocopherol content was sustained at high level until day-10 but drastically decreased at day-14 and remained at low level at day-21. However, RBC tocopherol level was not greatly responded to the dietary intake of tocopherol and was varied in the very narrow range. MDa levels of plasma and RBC were not responded in the same way as tocopherol content of plasma. MDa content of RBC was very low compared to that of plasma. RBC hemolysis by incubation in hypotonic solution was negatively correlated to plasma tocopherol level and was not correlated to the level of MDa in either plasma or RBC. There were no significant change in the levels of plasma cholesterol, HDL-chol, triglyceride, phospholipid, and lipoprotein pattern throught experimental periods.

• Korean Journal of Plant Resources
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• v.20 no.6
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• pp.553-557
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• 2007

The purpose of this study is to establish an extraction and analysis method for $\alpha$-tocopherol, and to then distinguish among varieties. The $\alpha$-tocopherol contents of 22 varieties of peanut seeds were analyzed by HPLC. Peanut seeds of cv. Palkwang were processed in two ways, by boiling and roasting. The $\alpha$-tocopherol contents of the two types of peanuts were compared with fresh seeds without any processing. $\alpha$-Tocopherol was detected at a retention time of 2.95 minutes. Five standards of $\alpha$-tocopherol covering a range of $20{\sim}100{\mu}g/ml$ were made up in 2% isopropyl alcohol/n-hexane and analyzed in duplicate. The $\alpha$-tocopherol contents differed according to extraction temperature. The contents were $85{\mu}g/g$ or less at $10^{\circ}C\;and\;20^{\circ}C$ and $94{\mu}g/g$ at $30^{\circ}C$, but they were decreased at $40^{\circ}C$ or higher. The $\alpha$-tocopherol contents in 22 peanut varieties were $61.36{\sim}96.80{\mu}g/g$ according to variety. Fresh peanuts contained $106.7{\mu}g/g$ of $\alpha$-tocopherol, while boiled peanuts contained $108.8{\mu}g/g$ of $\alpha$-tocopherol, and roasted peanuts contained $109.2{\mu}g/g$ of $\alpha$-tocopherol.

• Journal of Nutrition and Health
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• v.34 no.3
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• pp.306-312
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• 2001

We investigated the effect of physical exercise on the intakes and plasma levels of vitamin C and E in young male adults. The study population were divided into two groups: small-amount exercisers($\leq$ 30min/day, n=29) and moderate-amount exercisers(> 30min/day, n=32) according to their physical exercise habits measured by a questionnaire. Dietary intakes of vitamin C and E of the subjects were estimated by the 24 hour recall method. Plasma lipid profiles, vitamin C, $\alpha$-tocopherol and ${\gamma}$-tocopherol levels were analyzed. No significant differences were observed in total cholesterol, TG, HDL-C and LDL-C of plasma between two groups. Plasma vitamin C and $\alpha$-tocopherol levels in moderate-amount exercisers were significantly higher than those in small-amount exercisers, although dietary intakes of vitamin C and vitamin E were not significantly different between two groups. However, plasma ${\gamma}$-tocopherol level of moderate-amount exercisers did not significantly differ from small-amount exercisers. There was a positive correlation between the amount of exercise and plasma $\alpha$-tocopherol level. These results suggest that moderate amount of exercise over 30 min per day would lead to a healthy life with an activated antioxidant defence system against oxidative stress.(Korean J Nutrition 34(3) : 306~312, 2001)

• Proceedings of the Ginseng society Conference
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• 1984.09a
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• pp.113-118
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• 1984

The effect of the saponin fraction extracted from Panax ginseng C.A. Meyer on the antioxidant activity of ${\alpha}-tocopherol$ was investigated in vitro as well as in vivo. Microsomal preparation of albino rat (Sprague-Dawley, 180-200g) was incubated in the mixture containing NADPH, $Fe^{3+},$ ATP, ${\alpha}-tocopherol$ with and/or without ginseng saponin fraction for 30 minutes and the malondialdehyde formed was assayed and found that the saponin fraction stimulated the antioxidant activity of ${\alpha}-tocopherol$ cooperatively. It was also realized that the cooperative stimulation of the antioxidant activity of ${\alpha}-tocopherol$ was most eminent when the concentration of the saponin fraction was around $10^{-5}\%$ in the reaction mixture. Alcoholic suspension of ${\alpha}-tocopherol$ with and/or without ginseng saponin fraction was administered orally to rats in which the lipid peroxidation was induced by ethanol administration and the lipid peroxide contents of the liver were assayed at certain periods of time after ${\alpha}-tocopherol$ administration in this animal. It was reported that the saponin fraction stimulated the absorption of ${\alpha}-tocopherol$ in rats and this was confirmed again in the present work. From the previous work and present experimental results, it seemed that the saponin fraction accelerated the absorption of ${\alpha}-tocopherol$ and therefore stimulated the antioxidant activity of ${\alpha}-tocopherol$ more effectively in the animal body.

• Applied Biological Chemistry
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• v.25 no.4
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• pp.224-231
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• 1982

${\alpha}-Tocopherol$ was found to be a fluorescent probe in determination of the phasetransition temperature of liposome. Since this was a discovery of a new aspect of ${\alpha}-tocopherol$ as an important biochemical molecule, its molecular spectroscopic characterization was carried out in order to obtain some informations on its spectral and, structural properties in various media, anticipating that the compound may entertain a wide applications in biochemical systems as a spectroscopic probe. Two species of α${\alpha}-tocopherol$, monomer and dimer, were found to exist in organic media, especially in solvents of nonhydrogen bonding ability. Monomer with maximum UV-absorption around $(291{\sim}294nm)$ is highly fluorescent, while dimer which is formed by intermolecular hydrogen bonds and absorbes with spectral peak at 298nm is nonfluorescent. ${\alpha}-tocopherol$ incorporated to liposome exhibits emission property quite different from that in various organic media showing broad and red-shifted fluorescence excitation and emission spectra. This spectral abnormality is to be interpreted to arise from chromanolate-type ion, H-dissociated ${\alpha}-tocopherol$.

• Journal of Ginseng Research
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• v.12 no.2
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• pp.128-134
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• 1988

The effect of the saponin fraction extracted from Panax ginseng C.A. Meyer on the antioxidant activity of $\alpha$-tocopherol was investigated in vitro as well as in vivo. Microsomal preparation of rat(Winter, 180-200g) liver was incubated in the mixture containing NADPH, $Fe^{3+}$, ATP, $\alpha$-tocopherol with and/or without ginseng saponin fraction for 30 minutes and the malondialdehyde formed was assayed and found that the saponin fraction stimulated the antioxidant activity of $\alpha$-tocopherol cooperatively. It was also realized that the cooperative stimulation of the antioxidant activity of $\alpha$-tocopherol was most eminent when the concentration of the saponin fraction was around $10^{-5}$% in the reaction mixture. Alcoholic suspension of $\alpha$-tocopherol with and f or without ginseng saponin fraction was administered orally to rats in which the lipid preoccupation was induced by ethanol administration and the lipid peroxide contents of the liver were assayed at certain periods of time after $\alpha$-tocopherol administration in this animal. From the previous work and present experimental results, it seemed that the saponin fraction accelerated the absorption of $\alpha$-tocopherol and therefore stimulated the antioxidant activity of $\alpha$-tocopherol more effectively in the animal body.

• Plant Biotechnology Reports
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• v.5 no.1
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• pp.19-25
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• 2011

Tocopherols belong to the plant-derived poly phenolic compounds known for antioxidant functions in plants and animals. Activation of mitogen-activated protein kinases (MAPK) is a common reaction of plant cells in defense-related signal transduction pathways. We report a novel non-antioxidant function of ${\alpha}$-tocopherol in higher plants linking the physiological role of tocopherol with stress signalling pathways. Pre-incubation of a low concentration of $50{\mu}M$ ${\alpha}$-tocopherol negatively interferes with MAPK activation in elicitor-treated tobacco BY2 suspension culture cells and wounded tobacco leaves, whereas pre-incubated BY2 cells with ${\alpha}$-tocopherol phosphate did not show the inhibitory effect on stimuli-induced MAPK activation. The decreased MAPK activity was neither due to a direct inhibitory effect of ${\alpha}$-tocopherol nor due to the induction of an inhibitory or inactivating activity directly affecting MAPK activity. The data support that the target of ${\alpha}$-tocopherol negatively regulates an upstream component of the signaling pathways that leads to stress dependent MAPK activation.