we studied the effect of different concentrations of alpha-tocopherol on in vitro cupric ions induced oxidation of low density lipoproteins (ldl). human native ldl (50 µg protein/ml) oxidation was induced by 10 µmol/l of cuso4. conjugated dienes were measured spectrophotometrically for up to 440 minutes. the length of the lag phase (tlag), maximum velocity of the reaction (vmax) and the maximum...

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 fast...

A method for the analysis of tocopherol in human adipose tissue using high performance liquid chromatography and fluorescence spectrometry is described; results are expressed relative to total triglyceride content measured by the reaction of the methylated fatty acids with hydroxylamine and ferric chloride. The tocopherol contents of adipose tissue obtained at surgery and by the needle aspirati...

The effect on induction period and tocopherol content after γ-irradiation on samples of olive oil and seed oils (sunflower and soybean) was determined. In seed oil samples 0, 100, 200 and 300 ppm of δ-tocopherol were added before irradiation with 1, 2 and 3kGy. The results of induction period showed that, after irradiation, all samples presented a significant decreased in resistance to oxidatio...

Plasma and lipoprotein a-tocopherol concentrations of four patients with familial isolated vitamin E deficiency and six control subjects were observed for 4 d after an oral dose (15 mg) of RRR-a-tocopheryl acetate labeled with six deuterium atoms (d6-tocopherol). Chylomicron d6-tocopherol concentrations were similar in the two groups. d6-Tocopherol concentrations of plasma, very low (VLDL), low...

The aim of this experiment was to clarify the contribution of the alpha-tocopherol transfer activity of lipoprotein lipase (LPL) to vitamin E transport to tissues in vivo. We studied the effect of Triton WR1339, which prevents the catabolism of triacylglycerol-rich lipoproteins by LPL on vitamin E distribution in rats. Vitamin E-deficient rats fed a vitamin E-free diet for 4 wk were injected wi...

Although vitamin E has been known as an essential nutrient for reproduction since 1922, we are far from understanding the mechanisms of its physiological functions. Vitamin E is the term for a group of tocopherols and tocotrienols, of which alpha-tocopherol has the highest biological activity. Due to the potent antioxidant properties of tocopherols, the impact of alpha-tocopherol in the prevent...

Alpha-tocopherol is one of four tocopherol isoforms and has the highest vitamin E activity in humans. Most cultivated soybean seeds contain γ-tocopherol as the predominant form, and the ratio of α-tocopherol content to total tocopherol content (α-tocopherol ratio) is <10%. Three soybean accessions from Eastern Europe have α-tocopherol ratios of >20%. This higher content is likely due to mutatio...

An HPLC method for determination of αand γ-tocopherol in rat blood has been optimized and validated. The optimum means of separation and analysis of tocopherol homologs were selected on the basis of procedures found in the literature; documentary evidence is presented which shows precision and accuracy were satisfactory. Spectrofluorimetric detection was performed after separation on a Separon ...