D-a-Tocopherol acetate

In order to prepare C -labeled d-a-tocopherol we started from natural d-7-tocopherol (Fig. 6) and introduced the C -methyl group into the 5-position by use of the Mannich reaction. Condensation of d-y-tocopherol with radioactive paraformaldehyde in the presence of diethylamine followed by catalytic reduction gave d-a-tocopherol. This was acetylated to methyl-C Mabeled d-a-tocopherol acetate (specific activity 1.7 tc/mg Fig. 6). 

B subjects were on controlled experimentul diet, BE subjects were on same diet plus daily supplement of atleast 15 mg of d-a-tocopherol acetate daily, and IID subjects received the regular hospital diet, ad libitum. 

Hidiroglou, M. (1987) Vitamin E levels in sheep tissues at various times after a single oral administration of d-a-tocopherol acetate. Internat. /. Vit. Nutr. Res. 57, 381-384. 

A number of studies have demonstrated that the phytotoxic action of trifluralin and of other dinitroaniline herbicides can be antidoted with the use of compensation-type antagonists (for a review, see Ref. 121). Ascorbic acid, cysteine, 2,3-d-mercaptoethanol, and D-a-tocopherol acetate have all been reported to reduce growth inhibitions induced by trifluralin or other dinitroaniline herbicides.It is evident, however, that the antagonism of dinitroaniline herbicidal activity by these compounds does not seem to be related to the primary mechanism of action of these herbicides. As mentioned in Section 6.3.2, dinitroaniline herbicides act by interfering with the function and polymerization of plant microtubules. ... 

The a-tocopherol, P-carotene (ATBC) Cancer Prevention study was a randomised-controlled trial that tested the effects of daily doses of either 50 mg (50 lU) vitamin E (all-racemic a-tocopherol acetate), or 20 mg of P-carotene, or both with that of a placebo, in a population of more than 29,000 male smokers for 5-8 years. No reduction in lung cancer or major coronary events was observed with any of the treatments. What was more startling was the unexpected increases in risk of death from lung cancer and ischemic heart disease with P-carotene supplementation (ATBC Cancer Prevention Study Group, 1994). Increases in the risk of both lung cancer and cardiovascular disease mortality were also observed in the P-carotene and Retinol Efficacy Trial (CARET), which tested the effects of combined treatment with 30 mg/d P-carotene and retinyl pahnitate (25,000 lU/d) in 18,000 men and women with a history of cigarette smoking or occupational exposure to asbestos (Hennekens et al, 1996). 

Active analogues and related compounds include dl-a-Tocopherol l-a-toccpherol esters (succinate, acetate, phosphate), and fi, (. c.-tocopherol-,. The principal physiological forms are D-a-tocopherol. tocopheronolactone, and their phosphate esters. 

Procedure Transfer an accurately measured volume of the Test Solution, equivalent to about 100 mg of a-tocopherol, into a separator, and add 200 mL of water. Extract first with 75 mL, then with two 25-mL portions of ether, and combine the ether extracts in another separator. Add 20 mL of a 10% solution of potassium ferricyanide in a 1 125 sodium hydroxide solution to the ether solution, and shake for 3 min. Wash the ether solution with four 50-mL portions of water, discard the washings, and dry over anhydrous sodium sulfate. Evaporate the dried ether solution on a water bath under reduced pressure or in an atmosphere of nitrogen until about 7 or 8 mL remain, and then complete the evaporation, removing the last traces of ether without the application of heat. Immediately dissolve the residue in 5.0 mL of isooctane, and determine the optical rotation. Calculate the optical rotation [see Optical (Specific) Rotation, Appendix IIB], using as c the concentration of D-a-Tocopheryl Acetate, as determined in the Assay (above), in 100 mL of solution. 

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... 

Chaisuwan, P. Nacapricha, D. Wilairat, P. Jiang, Z. Smith, N.W. 2008. Separation of Qt-, P-, Y-, 5-tocopherols and a-tocopherol acetate on a pentaerythritol diacrylate monostearate-ethylene dimethacrylate monostearate-ethylene dimethacrylate monolith by capillary electrochemistry. Electrophoresis 29 2301-2309. 

Based on biological assay in vitamin E-deficient rats, the vitamers have widely varying biological activity. The original international unit (iu) of vitamin E potency was equated with the activity of 1 mg of (synthetic) dl- -tocopherol acetate on this basis, pure D-a-tocopherol (i i i -a-tocopherol, the most potent vitamer) is 1.49 iu per mg. The precise mixture of stereoisomers in this original standard is unknown, and the different stereoisomers have very different biological activities, so that different preparations may differ considerably. 

ACETATE a-TOCOPHEROL ACETATE d-tt-TOCO-PHEROL ACETATE (+)-a-TOCOPHERYL ACETATE a-TOCOPHERYL ACETATE d-tt-TOCOPHERYL ACETATE (R,R,R)-a-TOCOPHERYL ACETATE -(2R,4 R,8 R)-a-TOCOPHERYL ACETATE TOCOPHRIN TOFAXIN TOKOFEROL ACETATE VITAADN E ACETATE... 

Natural mixed tocopherols (E306), natural D-a tocopherol, natural o-a tocopherol acetate, natural D-a tocopherol succinate from soybean sources Vegetable oil-derived phytosterols and phytosterol esters from soybean sources Plant stanol ester produced from vegetable oil sterols from soybean sources Whey used in distillates for spirits Lactitol... 

Commercially available vitamin E consists of either a mixture of namrally occurring tocopherols and tocotriraiols (from natural sources), RRR-a-tocopherol (formerly called d-a-tocopherol), synthetic a-tocopherol, consisting of the eight possible side-chain stereoisomers at eqnal amonnts (all roc-a-tocopherol, formerly called dl-a-tocopherol), or their esters (a-tocophrayl succinate, a-tocopheryl acetate, a-toco-... 

In the second experiment 16 I.U. of pure samples of d(-a-tocopheryl acetate, d-a-tocopheryl acetate, dZ-a-tocopherol and d-a-tocopherol were force-fed in gelatin capsules to 4-week-old White Leghorn eockerels. In this experiment the feeding of the dose of vitamin E was so scheduled that all the birds would be sacrificed at the same time of day (3 p.m.) so as to minimize the effect of differences in fullness of crop and intestine on the... 

The response in liver tocopherol and plasma tocopherol after a single 8 I.U. dose is shown in Fig. 1. The curves for liver storage show a smooth rise and fall, peak storage occurring at 6 hours. The plasma tocopherol curve is more erratic, a rise at 1 hour being followed by a decline and then a maximum value for the dZ-a-tocopheryl acetate at hours and the d-a-tocopheryl acetate at 6 hours. These differences arc probably biological variations. 

When tocopherols or tocopheryl acetates are fed continuously over a period of time, however, equilibrium occurs so that the end result according to liver storage is in line with the actual biopotency. This was demonstrated by Pudelkiewicz et al. (1960), who found relative potencies by liver bioassay for ff/-a-tocopherol and d-a-tocopherol of 0.99 and 1.30, respectively, when fed in the diet in a stabilized form these values are not too far from their chemical equivalencies of 1.10 and 1.49, respectively. 

Unpublished results from our laboratory have shown that the brains of chicks raised for 5 weeks on an encephalomalacia-producing diet containing 30% lard, and on the same diet supplemented with 10 mg % dl-a- and 10 mg % d-a-tocopheryl acetate, respectively, contained 1.5, 1.9, and 2.2 Mg of tocopherol per gram of tissue, whereas the corresponding figures for liver were 1.0, 14.7, and 21.2 Mg/gm. 

The oi anization of the project has been described elsewhere (Horwitt et al., 1956 Horwitt, 1960). Briefly stated, 38 adult male subjects were divided into three groups group B (19 subjects) received a daily basiU diet which contained approximately 3 mg a-tocopherol group BE (9 subjects) received the same diet plus a supplement of 15 mg of d-a-tocopheryl acetate per day group HD (10 subjects) received the regular hospital diet ad libitum and served, in a sense, as positive controls. The basal diet, cor-... 

Styrene/butadiene polymer Copernica cerefera wax Copernicia cerifera wax. See Carnauba (Copernica cerifera) wax Copherol 1250. See d-a-Tocopheryl acetate Copherol F-1300. See D-a-Tocopherol Copisil . See Bentonite Copo 1500 Copo 1502 Copo 1505 Copo 1507 Copo 1712C Copo 1721. See Styrene/butadiene polymer Copolyester elastomer thermoplastic Copolyester, thermoplastic elastomer. See Polyester elastomer, thermoplastic Copolymer 186 Copolymer 186-85. See Castor oil, dehydrated... 

Covltol 1360. See Tocopheryl acetate Covltol F-350M. See Tocopherol Covltol F-600. See D-a-Tocopherol Covltol F-1000. See Tocopherol Cowclum Food Grade-10, Cowclum Tableting Grade. See Calcium phosphate monobasic anhydrous Cowrie. See Copal resin CoyoteStar XanPlex C, CoyoteStar XanPlex F,... 

DL-a Tocopherol. See Tocopherol (R,R,R)-a-Tocopherol. See,D-a-Tocopherol RRR-y-Tocopherol. See (+)-y-Tocopherol d,l-a-Tocopherol acetate ( )-o-Tocopherol acetate. See dl-a-Tocopheryl acetate a-Tocopherol acid succinate. See Tocopheryl succinate... 

Synonyms 2H-1-Benzopyran-6-ol, 3,4-dihydro-2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-, acetate 6-Chromanol, 2,5,7,8-tetramethyl-2-(4,8,12-trimethyltridecyl)-, acetate Syntopherol acetate 2,5,7,8-Tetramethyl-2-(4,8,12-trimethyltridecyl)-6-chromanol acetate d,l-a-Tocopherol acetate ( )-a-Tocopherol acetate... 

Calcium D-pantothenate Cholecalciferol Choline chloride Copper carbonate (ic) Cupric sulfate pentahydrate Ferrous fumarate Magnesium gluconate Magnesium sulfate anhydrous Manganese carbonate Manganese oxide (ous) Manganese sulfate (ous) Menadione DL-Methionine L-Methionine MSG Niacinamide D-Panthenol Potassium iodide Retinol Tocopherol D-a-Tocopherol DL-a-Tocopherol d-o-Tocopheryl acetate animal feed ingredient Casein Com (Zea mays) meal Lactose Sodium sulfate Whey animal feed supplement Ammonium acetate Ammonium perchlorate Calcium phosphate monobasic anhydrous Calcium pyrophosphate Cobalt phosphate (ous)... 

Thiosalicylic acid Thioxanthine Tocopherol D-a-Tocopherol DL-a-Tocopherol Tocophersolan Tocopheryl acetate d-a-Tocopheryl acetate dl-a-Tocopheryl acetate Tocopheryl linoleate Tocopheryl nicotinate d-a-Tocopheryl nicotinate Tocopheryl succinate o-Tolyl biguanide Triethyl citrate Tris (nonylphenyl) phosphite... 

Sulfur dioxide 3,3 -Thiodipropionic acid Tocopherol D-a-Tocopherol Tocopheryl acetate... 

Sodium hypophosphite Sodium metabisulfite Sodium sulfite Sodium thiosulfate anhydrous Stannous chloride anhydrous Sucrose Sulfur dioxide Thioglycerin Tocopherol D-o-Tocopherol Tocophersolan Tocopheryl acetate d-a-Tocopheryl acetate dl-o-Tocopheryl acetate ... 

Sodium ascorbate Sodium gluconate Sodium pantothenate Sodium phosphate dibasic heptahydrate Thiamine HCI L-Threonine Tocopherol D-a-Tocopherol pL-a-Tocopherol d-a-Tocopheryl acetate dl-a-Tocopheryl acetate DL-a-Valine L-Valine Zinc gluconate Zinc methionine sulfate Zinc sulfate Zinc sulfate heptahydrate nutrient, plant... 

The a-tocopherol molecule has three centres where stereoisomers can occur. The naturally occurring molecule is the D-a-tocopherol (or RRR-a-tocopherol) configuration and has the highest vitamin activity. Synthetic DL-a-tocopherol acetate (also called aU racemic a-tocopherol acetate) is used as a vitamin E supplement and comprises aU eight possible stereoisomers only one molecule in eight is in the RRR form. The vitamin activity of the four stereoisomers in the L forms is considerably lower than the four that make up the D forms in the latter the RRR form is the most active. 

The d-form of the vitamin is the most active. Any studies of vitamin supplementation, and their subsequent effects in various muscle foods, must acknowledge the form of tocopherol fed before conclusions can be drawn regarding dietary uptake and antioxidant efficiency, d-a-tocopherol or its ester is more readily assimilated into tissues than the racemic (dl) form (Hidiroglou et al., 1988). Burton et al. (1988) have demonstrated that the uptake of the free phenol and acetate forms of d-a-tocopherol are equivalent. Marusich et al. (1975) reported that dl-a-tocopherol and dl-a-tocopheryl acetate were equivalent in terms of uptake by chicken liver and breast muscle, and resulted in similar oxidative stabilities within the tissue types. 

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