• Applied Biological Chemistry
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• 제45권4호
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• pp.203-206
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• 2002

${\gamma}-Tocopherol$ methyltransferase(TMT)는 토코페롤 생합성 대사의 마지막 단계인 감마 토코페롤을 알파 토코페롤로 변환하는데 관여하는 효소이다. 들깨의 미성숙 종자 cDNA유전자 은행에서 TMT로 추정되는 유전자를 분리하였으며 이 유전자는 1369개의 염기와 367개의 아미노산으로 구성되었으며 분자량은 약 42kDa의 추정된다. 이 cDNA는 Genbank와 상동성 분석결과 애기장대의 TMT유전자와 아미노산 수준에서 60% 정도의 상동성을 가지고 있으며 methyltransferase domain과 S-adenosyl methionine binding domain을 가지고 있으므로 TMT 유전자로 추정했다. 이 유전자의 특성을 알기 위하여 완전한 크기를 가지는 TMT유전자를 대장균에서 발현하고 invitro에서 효소의 활성을 측정하였다.

• 한국동물번식학회:학술대회논문집
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• 한국동물번식학회 2001년도 춘계학술발표대회
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• pp.27-27
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• 2001

본 연구는 돼지 난포란의 체외 성숙시 hyaluronic acid (HA) 및 Tocopherol첨가가 돼지 수정란의 배발달에 미치는 효과를 검토하기 위하여 실시하였다. 돼지 난포란은 0.1% PVA, 3.05mM D-Glucose, 0.91mM sodium pyruvate, 0.57mM cysteine, 0.5$\mu\textrm{g}$/$m\ell$ LH, 0.5$\mu\textrm{g}$/$m\ell$ FSH and 10ng/$m\ell$ EGF가 첨가된 TCM-199에서 HA와 Tocopherol을 농도별로 첨가하여 42~44시간 배양함으로써 체외성숙을 유도하였다. HA의 효과를 보기 위해 체외성숙시 0.1% HA가 첨가된 처리구에서 배발달율은 25.6%로 대조구 16.7% 보다 높았다.(Table Omitted). 또한 수정시 HA를 0, 0.02, 0.2, 2.0 로 처리한 결과 8.7%, 19.4%, 11.1%, 0%로 대조구(8.7%)에 비해 0.02% 처리구(19.4%)에서 배발달율이 가장 높았다. 수정후 control, TCM-199, TCM-199+0.1% HA가 첨가된 배양액에 washing해주었을 때 발달율은 TCM-199+0.1% HA 첨가구에서 배발달율(35.6%)이 유의적으로 높게 나타났다. Tocopherol을 0, 50, 100, 200mM로 처리한 결과 수정된 난자중 배발달율은 32.1%, 40.0%, 35.7%, 39.6%로 처리구에서 높았으며, 성숙배양 후반기 22h. 동안 Tocopherol 첨가한 후 수정전 HA로 washing한 결과 Tocopherol 무첨가구에서는 차이를 보이지 않았으나, Tocopherol 첨가구에서는 HA처리구에서(19.0%)에서 무처리구보다(14.3%) 높은 결과를 나타내었다. 따라서 배양액내에 HA, Tocopherol를 첨가함으로써 미성숙 난포란의 수정율 및 발달율을 높일수 있을 것으로 생각된다.

• Clinical and Experimental Pediatrics
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• 제63권8호
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• pp.314-320
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• 2020

Background: The accumulation of unpaired α-globin chains in patients with β-thalassemia major may clinically create ineffective erythropoiesis, hemolysis, and chronic anemia. Multiple blood transfusions and iron overload cause cellular oxidative damage. However, α-tocopherol, an antioxidant, is a potent scavenger of lipid radicals in the membranes of red blood cells (RBCs) of patients with β-thalassemia major. Purpose: To evaluate the effects of α-tocopherol on hemolysis and oxidative stress markers on the RBC membranes of patients with β-thalassemia major. Methods: Forty subjects included in this randomized controlled trial were allocated to the placebo and α-tocopherol groups. Doses of α-tocopherol were based on Institute of Medicine recommendations: 4-8 years old, 200 mg/day; 9-13 years old, 400 mg/day; 14-18 years old, 600 mg/day. Hemolysis, oxidative stress, and antioxidant variables were evaluated before and after 4-week α-tocopherol or placebo treatment, performed before blood transfusions. Results: Significant enhancements in plasma haptoglobin were noted in the α-tocopherol group (3.01 mg/dL; range, 0.60-42.42 mg/dL; P=0.021). However, there was no significant intergroup difference in osmotic fragility test results; hemopexin, malondialdehyde, reduced glutathione (GSH), or oxidized glutathione (GSSG) levels; or GSH/GSSG ratio. Conclusion: Use of α-tocopherol could indirectly improve hemolysis and haptoglobin levels. However, it played no significant role in oxidative stress or as an endogen antioxidant marker in β-thalassemia major.

• Molecules and Cells
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• 제19권1호
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• pp.16-22
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• 2005

A cDNA encoding ${\gamma}-tocopherol$ methyltransferase (${\gamma}-TMT$) from Arabidopsis thaliana was overexpressed in lettuce (Latuca sativa L.) to improve the tocopherol composition. Seven lines of lettuce ($T_0$) containing the ${\gamma}-TMT$ transgene were produced by Agrobacterium-mediated transformation. The inheritance and expression of the transgene were confirmed by DNA and RNA gel blot analyses as well as quantification of tocopherols and ${\gamma}-TMT$ activities. The ratio of ${\alpha}-/{\gamma}-tocopherol$ content (TR) varied from 0.6 to 1.2 in non-transformed plants, while the $T_0$ plants had ratios of 0.8 to 320. The ratio ranged from 0.4 to 544 in 41 $T_1$ progenies of the $T_0$ transgenic line gTM3, and the phenotypic segregation indicated monogenic inheritance of the transgene (i.e., 3:1 = dominant:wild-type classes). There was a tight relationship between the TR phenotype and ${\gamma}-TMT$ activity, and enzyme activities were affected by the copy number and transcript levels of the transgene. The TR phenotype was stably expressed in $T_2$ progenies of $T_1$ plants. The results from this study indicated that a stable inheritance and expression of Arabidopsis ${\gamma}-TMT$ transgene in lettuce results in a higher enzyme activity and the conversion of the ${\gamma}-tocopherol$ pool to ${\alpha}-tocopherol$ in transgenic lettuce.

• 한국식품영양학회지
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• 제18권1호
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• pp.19-27
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• 2005

Antioxidative polyethylene films for food packaging were experimentally prepared by fortification of TBHQ(tertiary butylhydroquinone) and dl-a-tocopherol at the weight ratio of 0.05, 0.2 and 0.5%, respectively and laminated with nylon. TBHQ and tocopherol contents in the PE/nylon film were analyzed and the antioxidative effects of film were investigated on the lipid oxidation of semi-dried squid during storage at 5℃ and l5℃. TBHQ contents of TAP 1(TBHQ 0.05%), TAP 2(TBHQ 0.2%) and TAP 3(0.5%) were 38, 146 and 365 mg/100g, respectively. Tocopherol contents of DAP l(tocopherol 0.05%), DAP 2(tocopherol 0.2%) and DAP 3(tocopherol 0.5%) were 33, 139 and 356 mg/l00g, respectively. TBA value and POV during storage of semi-drid squid were affected both by storage temperatures and packaging films. Lipid oxidation during storage was retarded by anti-oxidative films, as TBA value of TAP 3 and DAP 3 revealed about 50% of control after storage at 5℃ for 20 days and similer effects in POV were also observed.

• Asian-Australasian Journal of Animal Sciences
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• 제17권7호
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• pp.1014-1018
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• 2004

Relationships between muscle $\alpha$-tocopherol oncentrations and metmyoglobin percentages during display of six muscles, m. serratus ventralis (SV), m. psoas major (PM), m. gluteus medius (GM), m. semimembranosus (SM), m. semitendinosus (ST) and m. longissimus lumborum (LL), of Japanese Black steers slaughtered at 28 months of age were studied. Steers were supplemented with 0, 2,000 and 4,000 mg $\alpha$-tocopheryl acetate/head/day for 28 days prior to slaughter in the VE 0, the VE 2,000 and the VE 4,000 groups, respectively. $\alpha$-Tocopherol concentrations in PM, GM, SM, ST and LL of the VE 2,000 and the VE 4,000 groups were significantly (p<0.05) higher than those of the VE 0 group. There were no significant (p>0.05) differences in $\alpha$-tocopherol concentrations in all muscles between the VE 2,000 group and the VE 4,000 group. The muscle $\alpha$-tocopherol concentrations ($\ell$/g meat) which can retard metmyoglobin formation in muscles were estimated to be 5.3 for SV, 4.5 for PM, 4.2 for GM, 4.0 for SM, 3.6 for ST and 3.5 for LL. The equation to predict color-shelf-life of each muscle from the $\alpha$-tocopherol concentration in each muscle could be obtained.

• 대한수의학회지
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• 제36권1호
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• pp.51-56
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• 1996

Clinical findings of white muscle disease or dystrophia were reported in Hokkaido horses from 1960. This disease was caused by selenium and $\alpha$-tocopherol deficiency. Therefore, this study were conducted to measure serum selenium and $\alpha$-tocopherol levels in Cheju island horses using feedstuffs containing volcanic ashes. The results were as follows : 1. The mean values of serum total selenium and $\alpha$-tocophcrol were $91.90{\pm}49.18ppb$(13.20ppb-193.80ppb) and $0.345{\pm}0.253mg/dl$(0.056mg/dl-1.159mg/dl) in female respectively. There were no significant relation between serum total selenium and $\alpha$-tocopherol levels. 2. 22%(15 of 68) of the horse examined showed selenium levels below 50ppb. 11.8%(8 of 68) showed $\alpha$-tocopherol levels lower than 0.10mg/dl. These results could be useful to diagnose of white muscle disease of Cheju island foals and quality control of feedstuffs of pregnant mares.

• Food Science and Biotechnology
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• 제18권2호
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• pp.526-532
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• 2009

Quenching mechanisms and kinetics of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol in photosensitized oxidation of lard were studied. Lard at 0.03, 0.07, 0.11, and 0.3 M in methylene chloride containing $4.4{\times}10^{-6}\;M$ chlorophyll and 0, 0.1, 0.3, and 0.6 mM $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol were stored under light for 4 hr, respectively. Oxidation was determined by headspace oxygen and peroxide value. Tocopherols prevented the photosensitized oxidation of lard (p<0.05). Steady state kinetic study showed that $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol prevented the photosensitized oxidation of lard by quenching singlet oxygen. Singlet oxygen quenching rates of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol by headspace oxygen depletion were 1.86, 2.39, 2.47, and $2.11{\times}10^7/M/sec$, respectively. The quenching rates of $\alpha$-, $\beta$-, $\gamma$-, and $\delta$-tocopherol by peroxide value were 1.42, 1.11, 0.97, and $0.42{\times}10^7/M/sec$, respectively. The quenching rates of tocopherols were slightly different depending on the measurements of oxidation.

• 한국식품영양과학회지
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• 제24권1호
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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.

• 약학회지
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• 제17권1호
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• pp.9-12
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• 1973

Determination of dl${\alpha}$-tocopherol and its acetate in their preparation through Infrared absorption spectrum was examined, using the sharp bands at 1085cm$^{-1}$ and 1210cm$^{-1}$ res[ectovely as the key bands. The accuracy of the determination was 100${\pm}$2% to the weight taken.