Ascorbic palmitate

The effects of antioxidants on protein oxidation were also studied in animal experiments. Barja et al. [73] demonstrated that feeding guinea pigs with vitamin C decreased endogenous protein oxidative damage in the liver. Administration of the mixture of antioxidants containing Trolox C, ascorbic palmitate, acetylcysteine, (3-carotene, ubiquinones 9 and 10, and (+)-catechin in addition to vitamin E and selenium to rats inhibited heme protein oxidation of kidney homogenates more efficiently than vitamin E + selenium [74]. 

Redox initiators have been proposed. The initiation system is composed from iron sulfate, dibenzoyl peroxide, and a reductant. Of the latter, hydroxyacetone, 2-hydroxy-2-phenylacetophenone, ascorbic palmitate, and toluene sulfinic acid are among the most economical. The reaction conditions are such that the cyclic oxida-... 

Ascorbyl palmitate and ascorbyl stearate are synthetic derivatives of ascorbic acid. Ascorbic palmitate is soluble in lipid-containing foods because of its relatively good hydrophobicity (88). Ascorbyl palmitate is hydrolyzed by the digestive system to provide nutritionally available ascorbic acid and palmitic acid, but health claims cannot be made for its vitamin C contribution. 

Saw palmetto gel caps are manufactured by two basic processes. The first uses hexane and the dried, powdered fruit. This is done in an inert gas atmosphere with antioxidants such as ascorbic palmitate. The second technique is more expensive but involves no solvent residues. Carbon dioxide is used in supercritical extraction (a high-tech method of extracting plant constituents, especially oils, under high pressure) to produce a product that is active and ready for use with no further purification. 

Cumene- or t-butyl hydroperoxide or t-butyl perbenzoate in conjunction with ascorbic acid or ascorbic palmitate also initiate rapid polymerization, yielding colorless composites with good mechanical properties (55). For commercial application, means must be developed for prevention of oxidation of ascorbic acid or its derivatives on prolonged storage. 

In principle, ascorbic acid and its salts (sodinm or calcinm ascorbate) are water solnble antioxidants, not widely applicable for lipid systems but extensively nsed in beverages. In aqneons systems containing metals, ascorbic acid may also act as a prooxidant by reducing the metals that become active catalysts of oxidation in their lower valences. However, in the absence of added metals, ascorbic acid is an effective antioxidant at high concentrations. The action of ascorbic acid in lipid autoxidation is dependent on concentration, the presence of metal ions, and other antioxidants. It has been shown that ascorbates can protect plasma and LDL lipids from peroxidative damage, and it may inhibit the binding of copper ions to LDL. " In several countries, ascorbic pahnitate is used in fat containing foods due to its lipid solubility. However whether ascorbic palmitate exerts a better... 

L-Ascorbic acid biosynthesis in plants and animals as well as the chemical synthesis starts from D-glucose. The vitamin and its main derivatives, sodium ascorbate, calcium ascorbate, and ascorbyl palmitate, are officially recognized by regulatory agencies and included in compendia such as the United S fates Pharmacopeia/National Formula (USP/NF) and the Food Chemicals Codex (FCC). 

Specifications for ascorbic acid, sodium ascorbate, calcium ascorbate, and ascorbyl palmitate are found in the Umted States Pharmacopeia J National Formula ... 

Bromophenol blue (3.0...4.6) aliphatic carboxylic acids [225 — 228] malonic and lactic acids [229] palmitic and lactic acids [230] malonic, glycolic, malic, citric, tartaric, ketoglutaric, galacturonic and oxalic acids [196] dicarboxylic acids, succinic acid [231] indoleacetic acid, trichloroacetic acid [232] palmitic acid, palmityl- and stearyllactic acid [223] benzoic, sorbic and salicylic acid [234] metabolites of ascorbic acid [235] chloropropionic acid [236] oligogalacturonic acids [237] amino acids, hydrocarbons, mono-, di- and triglycerides [238] xylobiose, xylose, glucose and derivatives [239] sugar alcohols [91] toxaphene [240]... 

To make ascorbic acid soluble in fats, it is reacted with fatty acids, such as palmitic acid, to form ascorbyl palmitate. This is used to prevent oxidation in fats and oils. 

Evidence exists that the relative solubility of amines and inhibitors in heterogeneous oil-water systems could be decisive in formation of nitrosamines and blocking these reactions, Nitrosopyrrolidine formation in bacon predominates in the adipose tissue despite the fact that its precursor, proline, predominates in the lean tissue (5,6,7). Mottram and Patterson (8) partly attribute this phenomenon to the fact that the adipose tissue furnishes a medium in which nitrosation is favored, Massey, et al, (9) found that the presence of decane in a model heterogeneous system caused a 20-fold increase in rate of nitrosamine formation from lipophilic dihexylamine, but had no effect on nitrosation of hydrophilic pyrrolidine. Ascorbic acid in the presence of decane enhanced the synthesis of nitrosamines from lipophilic amines, but had no effect on nitrosation of pyrrolidine. The oil-soluble inhibitor ascorbyl palmitate had little influence on the formation of nitrosamines in the presence or absence of decane. 

The criteria for choosing inhibitors in this study were the ability to compete with diethanolamine for the nitrite and lack of toxicity. An attempt was made to cover as broad a group as possible within the limits of feasibility. Ascorbic acid in its water soluble form and its oil soluble form, the palmitate, represent the enediols, Sorbate is a diene fatty acid which has been shown to inhibit nitrosation (10), Since the pK of sorbic acid is 4,76, at the pH of these experiments, both water soluble sorbate ion and oil soluble sorbic acid are present in significant amounts. Sodium bisulfite is a strong inorganic reducing agent which has an acceptable lack of toxicity at the concentration... 

Since a-tocopherol destroys nitrite in the system in absence of the oil phase, we may postulate that the ineffectiveness of these two oil soluble inhibitors resulted from their absence from the aqueous phase. Diethanolamine is miscible with water and presumably its nitrosation occurs in the aqueous phase. There is a significant difference in the solubility characteristics of ascorbyl palmitate. The reducing portion of the molecule is water soluble. Thus the ascorbate moiety may be in the aqueous phase while the fatty acid tails may lie within the oil globules. The a-tocopherol and the BHA may well be effective if they are dispersed in the aqueous phase after preparation of the emulsion. This will be investigated in future experiments. 

Palm oil carotenoid, tocopherol, and ascorbic acid palmitate were dissolved into com oil at 160°C for 30 min, emulsified with aqueous solution of gelatin, ascorbic acid, microencapsulated on saccharose at 70°C... 

The selection of an appropriate antioxidant depends on factors such as stability, toxicity, efficiency, odor, taste, compatibility with other ingredients, and distribution phenomena between the two phases. Antioxidants that give protection primarily in the aqueous phase include sodium metabisulfite, ascorbic acid, thioglycerol, and cysteine hydrochloride. Oil-soluble antioxidants include lecithin, propyl gal-late, ascorbyl palmitate, and butylated hydroxytoluene. Vitamin E has also been used, but its virtue as a natural antioxidant has been the subject of some controversy. 

Tocopherols are not as effective as antioxidants as the synthetic antioxidants, e.g. BHA or BHT. The antioxidant effect of tocopherols is increased by mixing them with ascorbyl palmitate, ascorbic acid, lecithin or citric acid. Typical confectionery applications are the use of tocopherols with ascorbyl palmitate or lecithin or citric acid in the fat phase of toffees or caramels. Chewing gum base can be treated with a- and y-tocopherol to extend the shelf life. 

E 304 Fatty acid esters of ascorbic acid (i) Ascorbyl palmitate (ii) Ascorbyl stearate... 

E 304 esters of fatty acids with ascorbic acid (i) ascorbyl palmitate (ii) ascorbyl stearate quantum satis... 

For non-standardised products tocopherols, tocopherol acetate, ascorbic acid and its sodium and calcium salts, ascorbyl palmitate, ascorbyl stearate, eiythorbic acid and stannous chloride (max. 0.0015% calculated as tin) may be used according to good manufacturing practice. 

Ascorbic acid and its sodium salt Eiythorbic acid and its sodium salt Ascorbyl palmitate... 

The main sources of vitamin C are green vegetables and citrus fruit. Animal tissue contains vitamin C, mainly in the kidneys and liver. The level of vitamin C in food is rapidly reduced during cooking or storage due to oxidation or water dissolution. It is added to food as an antioxidant (with no specified limit on the level of use) or as a supplement (with a maximum recommended daily intake of 3000mg/day). The forms admitted are L-ascorbic acid (AA), L-ascorbyl 6-palmitate, sodium, calcium, or potassium L-ascorbate [403]. 

Interest has been shown in using derivatives of ascorbic acid as antioxidants. One such compound is ascorbyl palmitate. In the structure of ascorbyl palmitate, the 2- and 3-positions are occupied by hydroxyl groups the 6-position contains the substituted fatty acid. Other derivatives, synthesized by Seib and associates were ascorbate-2 phosphate and ascorbate 2-triphosphate (27). Both of these compounds were reported to inhibit lipid oxidation in ground meat as measured by chemical means (2). Ascorbate-2-phosphate was also found to inhibit MFD in beef as measured by sensory means (2). The ascorbate-2-triphosphate was not tested as an inhibitor of MFD in this study, but... 

Benincase cerifera Savi. B. hispida Cogn. Don Gua (Gourd melon) (fruit, seed) Palmitic acid, stearic acid, linoleic acid, thiamine, riboflavin, niacin, ascorbic acid.50 Diuretic, laxative, treat diabetes, dropsy, rhinitis. 

Sodium, potassium, and calcium salts of ascorbic acids are called ascorbates and are used as food preservatives. These salts are also used as vitamin supplements. Ascorbic acid is water-soluble and sensitive to light, heat, and air. It passes out of the body readily. To make ascorbic acid fat-soluble, it can be esterified. Esters of ascorbic acid and acids, such as palmitic acid to form ascorbyl palmitate and stearic acid to form ascorbic stearate, are used as antioxidants in food, pharmaceuticals, and cosmetics. 

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