Delta tocopherol

Nilsson, J. L. G. Daves, D. G. Folkers, K. The oxidative dimerization of alpha-, beta-, gamma-, and delta-tocopherols. Acta Chim. Scand 1968, 22, 207-218. 

Rustan et al. (123) used an isocratic HPLC method for the determination of alpha-, gamma-, and delta-tocopherol, BHT, BHA, PG, OG, DG, NDGA, TBHQ, ascorbyl palmitate, and beta-carotene in foods. An RP18 column was used in experiments, and seven mobile phases based on various combinations of acetonitrile, methanol, water, and tetrahydrofuran were tested. Trials with carrot juice, dried milk formula for infants, and aperitif cakes showed that all 12 antioxidants could be determined by a single isocratic HPLC analysis. The optimum mobile phase... 

Andrikopoulos et al. (124) separated triglycerides, together with nine synthetic phenolic antioxidants most commonly used to prevent oxidation of edible oils and fats, as well as the natural antioxidants tocopherol and alpha-tocopherol acetate by HPLC using a reversed-phase Cl8 column and gradient elution with water/acetonitrile/methanol/isopropanol. Except for dilution of the oil with isopropanol/hexane, no further sample preparation was required. Ultraviolet detection was applied. The synthetic antioxidants PG, OG, DG, BHA, TBHQ, BHT, Ionox 100, THBP, and NDGA, as well as alpha- and delta-tocopherol and alpha-tocopherol acetate were separated. 

Composition and content of tocopherols in camelina oil was similar to perilla oil, where more than 80% of all tocopherols were gamma isomer (Table 4). Alpha and delta tocopherols were detected as minor antioxidants (77). The total content of tocopherols was comparable with perilla oil, and higher than that in flax oil (Tables 4 and 2). The total content of tocopherols in camelina oil is higher than canola, flax, soybean, and sunflower. 

Tocopherols are considered a moderate antioxidant in the peanut oil. The Codex Alimentaris standard for tocopherols in peanut oil (103) indicates a range of 48-373 mg/kg for alpha-tocopherol, 0-140 mg/kg for beta-tocopherol, 88-389 mg/kg for gamma-tocopherol, and 0-22 mg/kg for delta-tocopherol. Total tocopherol... 

It is important to note the difference between the seed oil and palm oil. Seed oils contain tocopherols. Palm oil contains tocotrienols in addition to tocopherols, and also a small amount of coenzyme QIO. Both tocotrienols and coenzyme QIO high antioxidant properties. Gamma- and delta-tocopherols, and their corresponding tocotrienols, are very effective in protecting oils from autoxidation (37). 

Tocopherols are already present in the oil. The amounts and the types of tocopherols vary with the type of oil. Most common types in seed oils are alpha-, gamma-, and delta-tocopherols. These compounds protect the oil from oxidation during processing, storage, transportation, and, also, later in the fryer. Tocopherols terminate the free radicals by reacting with them in the autoxidation reaction. This is why they are considered as free radical scavengers/quenchers. 

For various reasons, as described earlier, the freshly refined oil may contain lower than the desired level of tocopherols. In those cases, supplementing the oil with gamma- and delta-tocopherols or gamma- and delta-tocotrienols can significantly improve oxidative stability of the oil. This is not commercially practiced because of the high cost of the antioxidants. 

Melchert HU, Pabel E. Quantitative determination of alpha-, beta-, gamma- and delta-tocopherols in human serum by high-performance liquid chromatography and gas chromatography-mass spectrometry as trimethylsilyl derivatives with a two-step sample preparation. J Chromatogr A 2000 896(l-2) 209-15. 

Comments occurs naturally as 30% of the tocopherol content of soybean oil. Delta tocopherol is said to be the most potent antioxidant of the tocopherols. 

El 60 Carotenoids, Ethyl Ester of Beta-apo-8 192 E309 Delta Tocopherol 34... 

Alpha-tocopherol Beta-tocopherol Gamma-tocopherol Delta-tocopherol Total (mean)... 

Chaisuwan, P., Nacapiicha, D., Wilairat, P., Jiang, Z. Smith, N. W. (2008). Separation of Alpha-, Beta-, Gamma-, Delta-Tocopherols and Alpha-Tocopherol Acetate on a Pentaerythritol Diacrylate Monostearate-Ethylene Dimethacrylate Monolith by Capillary Electrochromatography. Electrophoresis, Vol. 29, No. 11, pp. 2301-2309, ISSN 0173-0835... 

Chang, L. C., Chang, H. T. Srm, S. W. (2006). Cyclodextrin-Modified Microemulsion Electrokinetic Chromatography for Separation of Alpha-, Gamma-, Delta-Tocopherol and Alpha-Tocopherol Acetate. Journal of Chromatography A, Vol. 1110, No. 1-2, pp. 227-234, ISSN0021-%73... 

Chen, T. H. Payne, G. F. (2001). Separation of Alpha- and Delta-Tocopherols Due to an Attenuation of Hydrogen Bonding. Industrial Engineering Chemistry Research, Vol. 40, No. 15, pp. 3413-3417, ISSN 0888-5885... 

The Czech patent describes a methodology for stabilizing polyolefins by mixture of the polymer with 100 to 50,000ppm (0.01 to 5%) of alpha-tocopherol, beta-tocopherol, gamma-tocopherol, delta-tocopherol, or mixtures thereof [9]. Although this patent covers polyolefins, and UHMWPE is, by definition, a polyolefin, UHMWPE was not specifically mentioned, nor were orthopedic hip and knee components. Furthermore, the actual methodology for mixing the polyolefin with vitamin E was also not disclosed by Dolezel and Adamirova. 

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