• Korean Journal of Plant Tissue Culture
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• v.27 no.6
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• pp.435-439
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• 2000

Explants of lettuce (Lactuca sativa L.) were cocultured with A. tumefaciens LBA 4404 harboring ${\gamma}$-tocopherol methyltransferase (${\gamma}$-TMT) gene from Arabidopsis thaliana. These explants were transferred to MS medium supplemented with 50 mg/L kanamycin, 500 mg/L carbenicillin, 0.1 mg/L NAA and 0.5 mg/L BA. After 4 weeks, kanamycin resistant shoots were obtained from the explants on the selection medium. The putative transgenic shoots were transferred to rooting MS medium supplemented with 50 mg/L kanamycin and 250 mg/L carbenicillin. Stable incorporation of the Arabidopsis ${\gamma}$-TMT cDNA into lettuce genomic DNA was confirmed by PCR and Southern analysis. HPLC analysis showed that $\alpha$- to ${\gamma}$-tocopherol ratio increased over four fold in a transgenic lettuce line indicating successful expression of the transgenic Arabidopsis ${\gamma}$-TMT in lettuce.

• Analytical Science and Technology
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• v.15 no.3
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• pp.248-255
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• 2002

The contents of ${\alpha}$-, ${\beta}$-, ${\gamma}$-, and $\delta$-tocopherols in sesame oils were determined by high performance liquid chromatography with UV detection. ${\alpha}$-Tocopherol contents ranged from 10.28 to 19.79 mg/g oil, ${\beta}$-tocopherol contents from 8.22 to 20.10 mg/g. However, both ${\gamma}$- and $\delta$-tocopherol were less than 1.49 mg/g or not detected. ${\gamma}$-Tocopherol was not detected from both unroasted white and black sesame seed oils. Significantly higher level of tocopherol in sesame oil than other oils is an evidence of the reason why it is highly stable and prevents oxidation. The tocopherol composition for twenty sesame oils was classified by using principal component analysis.

• 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.

• Food Science of Animal Resources
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• v.18 no.1
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• pp.1-8
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• 1998

This study was conducted to investigate the effects of $\alpha$-, ${\gamma}$-, $\delta$-Tocopherols on oxidative stability of lipid in hamburger patties during frozen storage. Hamburger patty samples were prepared with the addition of tocopherol by fat basis: control, treat 1 (control+0.02% $\alpha$-tocopherol), treat 2 (control+ 0.02% ${\gamma}$-tocopherol were cooked at 85$^{\circ}C$ for 3 minutes and the stored at -1$0^{\circ}C$ or 3$0^{\circ}C$). The fatty acids composition of the hamburger samples were analyzed during the storage periods (1, 20, 40, 60 and 80 days). there was no difference in the fatty acids composition among control and treatment groups in early storage time; however, content of unsaturated fatty acid was decreased in control group and slightly decreased or almost not changed in treatment groups as the storage period passed. No difference in the ratio of saturated fatty acid : unsaturated fatty acid (SFA : USFA) and saturated fatty acid : monounsaturated fatty acid : unsaturated fatty acid (SFA : MUFA : PUFA) between control and treatment groups at early storage time. However, SFA : USFA and SFA : MUFA : PUFA was decreased in control and slightly decreased or not changed in all treatment groups as the storage period passed.

• Journal of the Korean Society of Food Science and Nutrition
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• v.24 no.1
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• pp.67-73
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• 1995

Effects of tocopherols and $\beta$-carotene on the oxidation of the solid model system of a free fatty acid mixture (64.5% of linolic acid ; 26.4% of oleic acid ; 5.0% of palmitic acid) with tocopherols and $\beta$-carotene were studied. $\alpha$-tocopherol revealed an antioxidant activity at the concentration below 0.05%, however, it showed a prooxidant activity when the concentration was higher than 0.05%. The antioxidant activity of ${\gamma}$ -tocopherol was not affected by the concentrations in the range of 0.01~0.10% in the model and ${\gamma}$-tocopherol showed higher antioxidant activity than that of $\alpha$-tocopherol. It seemed that $\alpha$-tocopherol was unstable compared to ${\gamma}$-tocopherol during oxidation. $\beta$-carotene showed a weak antioxidative activity at the initial stage of this system while $\beta$-carotene showed a prooxidant activity in the presence of tocopherol. $\beta$ -carotene was highly susceptible to autoxidative degradation during oxidation.

• Nutrition Research and Practice
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• v.9 no.2
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• pp.192-198
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• 2015

BACKGROUND/OBJECTIVES: Vitamin E is a fat-soluble vitamin and functions primarily as a lipid antioxidant. Inadequate vitamin E status may increase risk of several chronic diseases. Thus, the objectives of this study were to estimate intake and plasma concentration of each tocopherol and to evaluate vitamin E status of Korean adults. SUBJECTS/METHODS: Three consecutive 24-h food recalls and fasting blood samples were collected from healthy 20- to 59-y-old adults (33 males and 73 females) living in the Seoul metropolitan area, South Korea. ${\alpha}$-, ${\beta}$-, ${\delta}$-, and ${\gamma}$-tocopherol intakes and plasma concentrations of tocopherols (${\alpha}$-, ${\delta}$-, and ${\gamma}$- tocopherol) were analyzed by gender. RESULTS: Dietary vitamin E and total vitamin E intake (dietary plus supplemental vitamin E) was $17.68{\pm}14.34$ and $19.55{\pm}15.78mg$ ${\alpha}$-tocopherol equivalents, respectively. The mean daily ${\alpha}$-tocopherol, and ${\gamma}$-tocopherol intakes were $3.07{\pm}2.27mg$ and $5.98{\pm}3.74mg$, respectively. Intakes of total vitamin E and each tocopherol of males were significantly higher than those of females (P < 0.05). Plasma ${\alpha}$-tocopherol concentration was $15.45{\pm}10.16$ of males and $15.00{\pm}4.54{\mu}mol/L$ of females, respectively. There were no significant differences in plasma tocopherol concentrations by gender ($P{\geq}0.05$). Plasma ${\alpha}$-tocopherol was negatively correlated with ${\gamma}$-tocopherol intake (P < 0.05). Twenty-three percent of the subjects had plasma ${\alpha}$-tocopherol concentrations < $12{\mu}mol/L$ indicating a biochemical deficiency of vitamin E. Approximately 8% and 9% of these participants had plasma ${\alpha}$-tocopherol:total lipid ratio less than $1.59{\mu}mol/mmol$ and plasma ${\alpha}$-tocopherol:total cholesterol ratio less than $2.22{\mu}mol/mmol$, respectively, which are also indicative of vitamin E deficiency. CONCLUSIONS: Vitamin E intakes of Korean adults were generally adequate with the Korean Dietary Reference Intakes for vitamin E. However, ${\alpha}$-tocopherol intake was lower than that reported in other countries, and 23% of the subjects in the current study were vitamin E deficient based on plasma ${\alpha}$-tocopherol concentrations.

• Journal of the Korean Society of Food Science and Nutrition
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• v.22 no.1
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• pp.96-100
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• 1993

The changes in the concentration of toropherol and carotenoid in pinenut oil at various stage of refining are studied during autoxidation. The oxidative stability of pinenut oil decreased with the refining degree increased. The tocopheol content of total crude oil was 55.51mg/100g oil and $\alpha$, ${\gamma}$and $\beta$-tocopherol in the crude oil were 25.48mg, 23.94mg and 6.99mg in order, respectively. The amount of $\delta$-tocopherol was trace. The concentrations of $\alpha$, ${\gamma}$ and $\beta$-tocopherol in pinenut oil after degumming or alkaline refining were 23. 85mg, 19.79mg and 6.12mg or 24.08mg, 24.04mg and 5.33mg, respectively. The content of f-carotene was 0.63% of total unsaponifiable materials and that of lycopene was trace. The concentrations of carotenoids and toropherols in pinenut oil decreased while autoxidation progressed. Degrees of destruction of carotenoids and toropherols. were significant at first stage of oxidation. Decrease in $\alpha$-toropherol was found to be faster than that in $\alpha$, ${\gamma}$-tocopherol during oxidation.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.48 no.6
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• pp.469-472
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• 2003

The rice bran has been known to contain tocopherols and tocotrienols carrying antioxidant and cholesterol-lowing activities. The content of 8 isomers of vitamin E : $\alpha\textrm{-}$, $\beta\textrm{-}$, $\gamma\textrm{-}$, $\delta\textrm{-}$tocoperols (T) and tocotrienols ($\textrm{T}_3$) were extracted from 18 major rice varieties and quantified with an HPLC. Tested varieties exhibited T, $\textrm{T}_3$ and total vitamin E ($\textrm{TT}_3$) contents ranging 9.1-14.8, 22.4-37.1, 34.9-46.5 mg/100g with averages of 11.1, 28.0, 39.2 mg/100g, respectively. Among tested varieties, Seojinbyeo and Hwasungbyeo showed high T contents and Andabyeo, Damakum were high in $\textrm{T}_3$, and Andabyeo and Seojinbyeo were high in total $\textrm{TT}_3$ contents. Regardless of varieties, the average 8 isomer contents (in mg/100g) were in descending order of $\gamma\textrm{-}$$\textrm{T}_3$(17.9) ＞$\alpha\textrm{-}$$\textrm{T}_3$(8.8) ＞$\alpha\textrm{-}$T (7.8) ＞$\gamma\textrm{-}$T(2.6) ＞$\delta\textrm{-}$$\textrm{T}_3$ (0.9)＞$\beta\textrm{-}$T (0.7)＞$\beta\textrm{-}$$\textrm{T}_3$ (0.4)＞$\delta\textrm{-}$T (0.1). In most varieties, $\gamma\textrm{-}$$\textrm{T}_3$, a strong antioxidant and anticancer compound, consisted 64% of total tocotrienol and 46% of total vitamin E in vice bran.

• Food Science and Biotechnology
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• v.15 no.2
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• pp.183-188
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• 2006

The tocopherol and tocotrienol contents of 39 vegetable oils, margarines, butters, and peanut butters typically consumed in the Korea diet were determined by direct solvent extraction method followed by normal phase liquid chromatography. All samples were locally obtained in the Cheongju area in 2003 and 2004. The study examined data on 19 vegetable oils, 10 margarines, 6 butters, and 4 peanut butters. ${\gamma}$-Tocopherol (${\gamma}$-T) and ${\alpha}$-tocopherol (${\alpha}$-T) were detectable in all products except butters and were usually present in the vitamin E form in greater quantity than the other isomers. Usually, ${\gamma}$-T content was higher than ${\alpha}$-T content in many samples. Tocotrienols were measurable in some samples but usually at levels less than the corresponding tocopherols. Three analytical method validation parameters, accuracy, precision, and specificity, were calculated to ensure the method's validity and were all confirmed to be reliable and satisfactory.

• Nutritional Sciences
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• v.9 no.4
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• pp.323-329
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• 2006

To more accurately estimate vitamin A and vitamin E intake of Koreans, food composition databases of the tocopherol and carotenoid contents of Korean foods are needed. In this study, the tocopherol $(\alpha-,\;\gamma-,\;and\;\delta-)$ and carotenoid ($\alpha-carotene,\;\beta-carotene,\;\beta-ctyptoxanthin$, lutein, and zeaxanthin) contents of 12 Korean cooked combination foods commonly consumed by children in Kwangju, Republic of Korea, were determined using reversed-phase HPLC. All samples were obtained from 3 different households in Kwangju during summer, 2005. All cooked foods in this study had detectable quantities of $\alpha-tocopherol,\;\gamma-tocopherol$ except for shoegogimugook, and $\delta-tocopherol$ except for myulchibokkeum Doejigogibokkeum had the highest $\alpha-tocopherol$ content (0.64 mg/l00 g edible portion), and $\gamma-tocopherol\;and\;\delta-tocopherol$ contents of gimbab were the highest among the foods (1.01 and 0.26 mg/l00 g edible portion). $\beta-carotene$ was found in all food samples. Gimbab had the highest contents of $\alpha-carotene,\;\beta-carotene$, and lutein among Korean cooked combination foods (158.3, 266.6, and $375.4{\mu}g/100g$ edible portion). Miyukgook contained only $\beta-carotene$ ($2.5{\mu}g/100g$ edible portion). Considerable sample-to-sample variability in tocopherol and carotenoid compositions were observed in several Korean cooked combination foods included in this study. Some of these carotenoids $(\alpha-carotene,\;\beta-carotene,\;and\;\beta-cryptoxanthin)$ are vitamin A precursors. The findings of this study may be valuable for use in Korean databases as well as nutrient consumption research for vitamin A and vitamin E.