Tocopherols Concentrate, Mixed

RRR-Tocopherols Concentrate, Mixed / Monographs Function Nutrient antioxidant. 

Ammonium Hydroxide DL-a-Tocopherol D-a-Tocopherol Concentrate Tocopherols Concentrate, Mixed D-a-Tocopheryl Acetate DL-a-Tocopheryl Acetate D-a-Tocopheryl Acetate Concentrate D-a-Tocopheryl Acid Succinate... 

Gum Arabic Ammonia Solution All-rac-a-Tocopherol RRR-a -T ocopherol RRR-Tocopherols Concentrate, Mixed RRR-a-Tocopheryl Acetate All-rac-a-Tocopheryl Acetate RRR-a-Tocopheryl Acetate Concentrate RRR-a-Tocopheryl Acid Succinate... 

AOAC 988.14 Tocopherol Isomers in Mixed Tocopherols Concentrate, Gas Chromatographic Method (First Action 1988)... 

This monograph establishes specifications for two types of mixed tocopherols concentrate. Both types are obtained by the vacuum steam distillation of edible vegetable oil products, and both contain a specified minimum amount of total tocopherols (see Requirements, below), differing only in the levels of the RRR-tocopherol forms. 

Mixed RRR-Tocopherols Concentrate occurs as a brown-red to light yellow, clear, viscous oil. It may show a slight separation of waxlike constituents in microcrystalline form. It oxidizes and darkens slowly in air and on exposure to light, particularly when in alkaline media. It is insoluble in water soluble in alcohol and miscible with acetone, with chloroform, with ether, and with vegetable oils. 

The reactions are carried out under first-order conditions, i.e., the stoichiometric concentration of the antioxidant, a-tocopherol, is in large excess over that of 16-ArN, such that the concentration of a-tocopherol does not change significantly throughout the time course of the reaction. The emulsion employed was prepared by mixing the non-ionic emulsifier Brij 30, octane and HCl (3 mM, pH = 2.5). The resulting emulsion is opaque, thus values were obtained electrochemically by employing Linear Sweep Voltammetry (LSV). 

Tocopherols and tocotrienols, collectively known as tocols, are monophenolic and lipophilic compounds that are widely distributed in plant tissues (7). The main commercial source of natural tocopherols is the soybean oil. Tocotrienols, less common than tocopherols, are present in palm oil, rice bran oil, as well as cereals and legumes (11). Tocopherols and tocotrienols are classified into a-, (3-, y-, and 5-, depending on their chemical structures (Figure 7). In general, tocotrienols have a stronger antioxidant effect on lipid oxidation than tocopherols. The antioxidant activity of tocopherols is dependent on temperature and is in the order of 5- > y->P-> oc-tocopherol (7). Tocopherols (mixed natural concentrate) are a golden... 

The richest sources of vitamin E in the diet are vegetable oils. a-Tocopherol is the major contributor to the total vitamin E activity in some oils, but others contain substantial amounts of y-tocopherol (Figure 6.5). Typically, wheat germ, sunflower, cottonseed, and safflower oils contain about 1700, 500, 400, and 350 mg of a-tocopherol equivalent kg-1, respectively. Tocopherols are concentrated in deodorizer distillate (DOD) during the deodorization step. As a result, DOD is a good source of natural tocopherols that are used to make natural vitamin E. DOD is composed of FAs, mixed mono-, di-, or triacylglycerols, sterols, tocopherols, sterol esters, hydrocarbons, and oxidation by-products. DOD is frequently collected and sold. A... 

About one tenth of the total amount of vitamin E produced is semi-synthetic, isomerically pure (2R,4 K,8 R)-a-tocopherol (RRR-3) which is used almost exclusively in human applications (mainly pharma). This product, originating from natural sources, is obtained from soya deodorizer distillates (SDD). Vegetable oils refined on a large scale are the major sources of vitamin E compounds [26-28]. The deodorizer distillate, originally a waste stream, contains considerable amounts (up to 10%) of a-, [I-, y- and b-tocopherols (RRR-3 to RRR-6) which are isolated by several separation methods. To increase the value of the vitamin E concentrate of mixed tocopherols obtained from SDD, the lower (I-, y- and d-homologues (RRR-4 to RRR-6, content ca. 90%) have to be transformed subsequently into the biologically more active a-tocopherol (RRR-3, only ca. 5% in the original mixture) by permethylation reactions. Permethylations are performed by chloro-, amino-, or hydroxymethylation reactions to provide functionalized alkylated intermediates, which are reductively converted into RRR-3 (Fig. 3) [29]. 

Fat-soluble vitamins such as retinol and )3-carotene are readily dissolved in mixed lipid-bile salt micelles in vitro. Retinol is approximately 10 times more readily dissolved in such micelles than /3-carotene [105]. It is likely that these two substances occupy different regions of the micelle. The difference in solubility, therefore, may reflect the limited capacity of the nonpolar core of the micelle for the relatively bulky /3-carotene molecule. Retinol, on the other hand, may occupy a more hydrophilic region of the micelle. In a mixed oil/micellar system, a-tocopherol distributes between the two phases, its concentration in the micellar phase being enhanced by expansion of the micelles with monoglycerides and lecithin of long-chain fatty acids. However, lipids containing medium-chain fatty acids do not expand the micelles as effectively as their long-chain counterparts such that there is less solubilization of a-tocopherol in the micellar phase [106]. 

S-Tt>capherol, 3,4-Hihydro-2,8 1 i methyl. 2- 4,8,-12-trimethyUridecyl)-2H-l-benzopyran-6-ol 8-methyltocol. C H O, mol wt 402-64. C 80.54%, H 11.52%, O 7.95%. Appears to be a rather common member of the vitamin E complex. Ingredient of Mixed Toeopherols Concentrate, N.F. It was found to constitute approx 30% of the mixed toeopherols in soybean oil. 5% of those in wheat germ oil. and there is evidence of its occurrence in cottonseed and peanut oils. Claimed to be the most potent antioxidant of the toeopherols. It has only one hundredth of the activity of natural -tocopherol in the Evans resorption sterility test for vitamin E. Lsoln from soybean oil Stern et al., J. Am ... 

Prepare individual standards (Sigma) of vitamin A palmitate, vitamin D2 (calciferol), and vitamin E (dl-a-tocopherol) as l-pg/pl solutions in benzene. Prepare each standard by dissolving 10 mg of the vitamin in 10 ml of benzene (benzene is a carcinogen and should be handled with extreme care). Prepare a mixed standard of the three vitamins by weighing 10 mg of each vitamin and dissolving in 10 ml of benzene to achieve a concentration of 1 pg/lil for each. 

Table 1. Extractive separation of mixed tocopherols using [CimimjCl at 303.15 K. Initial concentration of tocopherol in hexane (mg/ml) 0.54, 0.53, a 0.11. Volume ratio of two phases 1 1. a) methanol amount was adjusted to reach an equilibrium phase volume ratio about 1 1. b) carried out at 328.15 K, mixed for 18 h. Reprinted from reference which is downloaded from pubs.acs.org (Yang et al., 2009).

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