Synthetic alpha tocopherol

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. 

Satoh, K., Kadofuku, T., and Sakagami, H., Effect of Trolox, a synthetic analog of alpha-tocopherol, on cytotoxicity induced by UV irradiation and antioxidants, Anticancer Res., 17, 2459, 1997. 

Burton, G.W. et al., Eluman plasma and tissue alpha-tocopherol concentrations in response to supplementation with deuterated natural and synthetic vitamin E, Am. J. Clin. Nutr., 67, 669, 1998. 

In fractions of butteroil containing alpha-tocopherol and copper. These workers reported that l,5-octadlen-3-one from the oxidation of long-chain polyunsaturated n-3 fatty acids was responsible for metallic notes, but the fishiness appeared to be contributed by the 2,A,7-decatrlenals or a combination of these compounds. This relationship has been explored further In our laboratory through mechanistic studies employing alpha-tocopherol and Trolox C which Is a synthetic tocopherol-type antioxidant (Figure 2). 

Note that alpha tocopherol has three chiral centers, giving rise to eight isomeric forms. The naturally occurring form is known as d-alpha tocopherol or (2R,4 R,8 R)-alpha-toco-pherol. The synthetic form, d/-alpha tocopherol or simply alpha tocopherol, occurs as a racemic mixture containing equimolar quantities of all the isomers. 

Naturally occurring tocopherols are obtained by the extraction or molecular distillation of steam distillates of vegetable oils for example, alpha tocopherol occurs in concentrations of 0.1-0.3% in corn, rapeseed, soybean, sunflower, and wheat germ oils. Beta and gamma tocopherol are usually found in natural sources along with alpha tocopherol. Racemic synthetic tocopherols may be prepared by the condensation of the appropriate methylated hydroquinone with racemic isophy-tol.<">... 

Currently, the bulk of commercial vitamin E is synthetic dialpha-tocopherol acetate, an ester of alpha-tocopherol, a form more stable to heat and oxidation than the free alcohol form, but with the same vitamin E activity. This stable form of alpha-tocopherol is added to vitamin preparations, various medicinal products, foods, and animals feeds. 

Free radical scavenging activities of different phenolic acids, caffeic acid (CA), ferulic acid (FA) and p-coumaric acid (p CA) and natural antioxidants alpha tocopherol (alpha-toco) and BHA a synthetic antioxidant were compared with sinapic acid (SA). As indicated in Figure 15.10 under the tested conditions, the radical scavenging activity of the phenolic acids in the DPPH system decreased in the following order ... 

First identified Spice included fatty acids (linoleic acid, palmitic acid, oleamide), plant-derivate products (thymol, vanillin), preservatives (paraben family), and vitamins (alpha-tocopherol) [21-24]. Modem Spice products contain only synthetic cannabinoids and plant-derivate substances explaining by home-made manufacturing. 

Alpha-d-tocopherol can also he readily synthesized in the laboratory. In the course of the synthesizing process, however, alpha-d-tocopherol is produced together with alpha-l-toco-pherol, its mirror-image molecule. The latter is not found in nature, and it has less biological activity than the so-called d-isomer. To get aroimd this confusing business, we rate vitamin E supplements in terms of international units (lu) of activity. In other words, the composition of the synthetic and the natural versions may not be identical, but a two himdred lu tablet will have the same level of activity, regardless of its origin. 

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