E Tocopherols

Vitamin E, a fat-soluble vitamin, is used in vitamin E deficiency in premature infants and in patients with impaired fat absorption (including patients with cystic fibrosis) and in biliary atresia. Sources are eggs, vegetable oils, margarine, and mayonnaise nuts and seeds fortified cereals green leafy vegetables. 

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E Tocopherols, tocotrienols Antioxidant, especially in cell membranes Extremely rare—serious neurologic dysfunction... 

Vitamin E (tocopherol) is the most important antioxidant in the body, acting in the lipid phase of membranes and protecting against the effects of free radicals. Vitamin K functions as cofactor to a carboxylase that acts on glutamate residues of clotting factor precursor proteins to enable them to chelate calcium. 

Fluorimetric methods of analysis make use of the natural fluorescence of the analyte, the formation of a fluorescent derivative or the quenching of the fluorescence of a suitable compound by the analyte. Fluorescence cannot occur unless there is light absorption, so that all fluorescent molecules absorb, but the reverse is not true only a small fraction of all absorbing compounds exhibits fluorescence. The types of molecule most likely to show useful fluorescence are those with delocalised ji-orbital systems. Often, the more rigid the molecule the stronger the fluorescence intensity. Naturally fluorescent compounds include Vitamin A, E (tocopherol). 

Although there are physiologically significant quantities of vitamin E (tocopherol) and vitamin K (phylloquinone) in black tea, their extractabil-ity is not adequately known.110... 

Vinu and co workers also reported systematic research on the adsorption of vitamin E (tocopherol) on activated carbon (plot (a)) and CMK-3 (plot (b)) in heptane solutions of vitamin E (Figure4.24) [195,196]. Up to an initial solution concentration of vitamin... 

Fig. 4.24 Adsorption isotherms of vitamin E (tocopherol) on carbon adsorbents (a) activated carbon (b) CMK-3. Reprinted with permission from [195], M. Hartmann et ai, Chem.Mater.

Vitamin E (tocopherol), which is a major lipid-soluble antioxidant, inhibits the differentiation of smooth muscle presumably by modulating the activity of protein kinase C. PKC inhibition by tocopherol has also been implied in human platelets. 

Choy et al. [193] reported that vitamin A (retinoic acid), vitamin C (ascorbic acid) and vitamin E (tocopherol) could be intercalated into Zn/Al LDHs by the coprecipitation method. In solutions, these vitamins are normally all sensitive to light, heat and oxygen, and it was proposed that incorporating the molecules into a layered inorganic lattice may lead to their stabilization, resulting in a wider range of potential apphcations. 

Vitamin E (tocopherol) Vegetable seed oils, milk, eggs, meat Antioxidant... 

Vitamin E (tocopherol) and related compounds only occur in plants (e.g., wheat germ). They contain what is known as a chro-man ring. In the lipid phase, vitamin E is mainly located in biological membranes, where as an antioxidant it protects unsaturated lipids against ROS (see p. 284) and other radicals. 

Methyl groups of the aromatic ring of vitamins E and K have been replaced by trifluoromethyl. Replacement of the three methyls of the side chain by one or several trifluoromethyls (Wittig-Uke approach from ad hoc trifluoromethyl ketones) as well as the difluorination at CA (synthesized from bromodifluoroacetate) in vitamin E (tocopherol) have also been realized (Eigure 4.28). " The relaxation times T2 of the various CF3 groups have been measured in suspensions of hposomic bilayers and compared to those obtained in solution. The goal of these studies was to determine the mobility and the molecular orientation of the vitamin in a lipidic bilayer. 

One of the simplest and most significant of the diterpenes is phytol, a reduced form of geranylgeraniol, which constitutes the lipophilic side-chain of the chlorophylls. Phytol also forms a part of vitamin E (tocopherols) and K molecules. Vitamin A is also a 20-carbon-containing compound, and can be regarded as a diterpene. However, vitamin A is formed from a cleavage of a tetraterpene. Among the medicinally important diterpenes, paclitaxel, isolated from Taxus brevifolia (family Taxaceae), is one of the most successful anticancer drugs of modern time. 

Addition of Active C-H Compounds to Dienes the Rhone-Poulenc Process for Geranylacetone - Geranylacetone is a precursor of isophytol, a key intermediate in the manufacture of vitamine E (tocopherol) (see Figure 16), the world market of which is 10 000 t/a at a price of 25-30 /kg tocopherylacetate.54... 

Vitamin E (tocopherol) Inhibits oxidation of polyunsaturated fats free radical scavenger helps maintain circulatory and nervous systems Diminished hemoglobin... 

Commercial production of vitamin E tocopherols is by way of molecular distillation from vegetable oils. 

Association of Vitamin Chemists. Vitamin E (tocopherols). Methods of Vitamin Assay. 3rd ed. New York Interscience, 1966, pp 363-402. 

Vitamin E (tocopherol) possesses antioxidative properties, which means it can protect polyunsaturated fatty acids from auto-oxidation. Deficiency of vitamin E causes increased peroxidation of lipids, which consequently leads to elevated production of prostaglandins. Increased concentration of prostaglandins, in turn, retards... 

Vitamin E, (tocopherols) C29H50O2 (Figure 6.8), which acts as an anti-oxidant to prevent the free radical oxidation of lipids in cell membranes. There are sufficient supplies of vitamin E in vegetable oils. 

They facilitate the intestinal absorption of fat-solnble vitamins (vitamin A, retinol vitamin D, cholecalciferol vitamin E, tocopherol and vitamin K). 

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