Vitamins liposoluble

MM Delgado Zamarreno, A Sanchez Perez, MC Gomez Perez, J Hernandez Mendez. Directly coupled sample treatment—high-performance liquid chromatography for on-line automatic determination of liposoluble vitamins in milk. J Chromat A 694 399-406, 1995. 

In other terms, once an RS reacts with lipids, the propagation starts, which can be quenched only by the so-called chain breakers antioxidants (usually liposoluble antioxidants) such as vitamin E. This is one of the reasons for the presence of vitamin E in the cellular membranes. 

Vitamins Vitamins are organic compounds essential for the correct development of organisms. Therefore, foods, and especially milk, must supply them at the needed amounts. Normal values of vitamins in human and cow milk are summarized in Table 13.5. In general terms, vitamins can be classified as hydrosoluble and liposoluble. According to this feature, the liposoluble A, D, E, and K vitamins are in fat globules, while the remaining vitamins are in milk plasma. 

Vitamins In particular, water-soluble vitamins have to be provided in adequate quantities. With a carbohydrate diet and alcoholic liver disease, the daily requirement is higher. A daily intake of multivitamins, best combined with trace elements and minerals, is recommended. As a rule, liposoluble vitamins are best administered by parenteral route due to inadequate absorption. The therapeutic significance of zinc (s. pp 50, 99) should always be borne in mind. (34, 153, 155,169)... 

Methods for control and standardization of drugs containing liposoluble vitamins 01KFZ( 10)41. 

Another aspect of the anti-oxidant properties of HA concerns it presence in some foods. Food anti-oxidants have recently drawn much attention because of a possible protective role against damage caused by free radicals, including the rising of some neoplastic forms as well as cellular senescence. These anti-oxidants can be used to slow down the process by which oils and fats grow rancid, and to protect liposoluble vitamins. 

Two compositions of the liposoluble vitamin K compound phytomenadione are listed in Table 37.7. In (4) a nonionic surfactant is used, in (5) lecithin-bile acid mixed micelles are the solubilizing principle. 

When acceptable frying practices are applied and the oil is discarded regularly, the oil remaining in the fried food retains its nutritive value and a significant portion of the liposoluble vitamins. The fried product retains water-soluble vitamins, minerals, and other nutrients to a greater extent than in other cooking methods. 

The formation of polymers leads to an increase in viscosity. The various lipids that can leach into the frying oil change the properties and the performance of the frying oil. Colored lipids solubilized in the oil contribute to the darkening. Phospholipids are emulsifiers. Traces of liposoluble metal compounds may act as prooxidants. Liposoluble vitamins and phenolic compounds are antioxidants. Volatile compounds (e.g., from fish or onions) contribute to off-flavors. 

Since vitamins are unstable and easily deteriorate, it is necessary to devise a formulation that will stabilize them. One effective method of achieving this is the use of various CyD inclusion complexes. In particular, y-CyD is becoming popular for the purposes of making liposoluble vitamins soluble in water, powdering them, or stabilizing them and increasing their bioavailability. 

Even the liposoluble vitamin E (tocopherol), which is unstable under sunlight, UV light, or heat, can be stabilized with y-CyD. When a mixture of tocopherol and starch was kept at 45 °C, 60% of its activity was lost in 17 weeks. But under the same conditions, y-CyD-included tocopherol lost only 20% of its activity. 

Gonnet, M., Lethuaut, L., Boury, F 2010. New trends in encapsulation of liposoluble vitamins. Journal of Controlled Release, 146(3) 276-290. 

Uses Surfactant, solubilizer for essential oils and liposoluble vitamins Trade Name Synonyms Remcopal HC 33 f[Ceca SA http //www.ceca.fi]... 

Sodium myristyl sulfate Sodium petroleum sulfonate TEA-lauryl sulfate Undeceth-8 surfactant, leather auxiliaries Lauryl phosphate surfactant, leather treatment Lecithin PEG-10 stearate surfactant, leather working Nonyl nonoxynol-1.5 Nonyl nonoxynol-2 surfactant, light duty detergents Ammonium laureth sulfate surfactant, liniments Sodium C12-18 alkyl sulfate surfactant, lip care Diisostearyl malate surfactant, liposoluble vitamins PEG-33 hydrogenated castor oil surfactant, lipsticks Myreth-3 myristate surfactant, liq. cleaners heavy-duty Sodium cocoamphoacetate... 

Dietary and endogenous fats are carried to the target organs by different lipoproteins, i.e. chylomicrons, LDL and HDL. These particles contain a core of TAG liposoluble vitamins and cholesteryl esters, surrounded by a phospholipid and free cholesterol layer. These also contain, by the way, specific proteins, called apolipoproteins (apo) which act as enzyme cofactors or receptor ligands. Exogenous fat is transported in chylomicrons from the intestinal epithelium to the peripheral cells, reaching the bloodstream via flie lymphatic system [11],... 

Escriva, A. Esteve, M.J. Farre, R. Fngola, A. Determination of liposoluble vitamins in cooked meals, milk and milk products. J. Chromatogr. A, 2002, 947, 313-318. 

Vitamin A is essentially a liposoluble vitamin, and therefore a diet that contains little animal fat—such as a pure rice diet—often leads to vitamin A deficiency. In contrast, the deficiency is rare in countries where animal fats are abundant in the diet, as in the United States and Western European countries. Butter, milk, cream, fat cheeses, cod liver oils, egg yolks, liver, and brain are among the animal sources richest in vitamin A. An interesting relationship between vitamin A deficiency and its sources in the diet was observed during the First World War in Denmark. The Danish farmers, who produced much of the western world s milk and butter during that time, were so anxious to sell their products to foreign countries that little of it was consumed within the country. This resulted in the development of an epidemic of night blindness and xerophthalmia. 

Since carotenes and vitamin A are liposoluble, any condition that interferes with lipid absorption—for example, steatorrhea— will cause vitamin A deficiency. The vitamin is also easily oxidized, and the oxidized form is inactive. Therefore, antioxidants or tocopherol in the intestinal content improves vitamin A absorption. 

Because other liposoluble vitamins (K and E) have often been implicated in the electron transport chain, the effects of vitamin A on mitochondria and mitochondrial enzymes have also been investigated. Although the mitochondrial respiration rate may be decreased in vitamin A-deficient animals, there is no change in the activity of succinoxidase or the enzymes of the Krebs cycle. Some investigators claim that cytochrome c reductase activity is decreased in tissues of vitamin A-deficient animals. A decrease in trans-hydrogenase activity of liver mitochondria and an increase in NADPH cytochrome c reductase has also been described in vitamin A deficiency. Ubiquinone is consistently in excess in deficient rats but not in chickens. 

The vitamin is absorbed through the intestine by a mechanism similar to that involved in the absorption of other liposoluble vitamins consequently, intestinal disorders leading to lipid malabsorption are associated with malabsorption of vitamin E. Humans with such malabsorption syndromes have reduced levels of vitamin E in their tissues. They do not show classical symptoms of muscular dystrophy, although a certain degree of muscular fatigue may be observed. 

Provitamin and vitamin D are liposoluble compounds, and their absorption in the intestine depends on lipid absorption. Intestinal diseases accompanied by pronounced steatorrhea result in vitamin D deficiency with osteomalacia and rickets. Although vitamin D was one of the first vitamins to be identified, it is only recently that its role in metabolism has been clarified. The mechanism of action of vitamin D raises problems at the histological and the molecular level Which tissues are the target of vitamin D What are the intricacies of the molecular reaction involving vitamin D in calcification ... 

Vitamin K deficiency may also result from absorption defects in the gastrointestinal tract. Vitamin K is a liposoluble vitamin thus, whenever there is interference with lipid absorption in the intestine, poor absorption of the vitamin ensues. Two groups of diseases primarily are associated with inadequate lipid absorption—obstructive jaundice and malabsorption conditions in the intestine. Among the latter are included sprue, regional ileitis, intestinal obstruction, intestinal lipodystrophy, short-circuiting anastomosis, hyperperistalsis, chronic dysentery, and ulcerative colitis. 

In obstructive jaundice, bile salts are not excreted in the intestine, and therefore their beneficial effects on fat solubilization and lipid absorption through the intestinal epithelium are lost. Consequently, the liposoluble vitamins are lost in the stools. Vitamin K is also synthesized by the bacterial flora of the intestine. When antibiotics are administered to cure intestinal infection by pathogens, they also eliminate the sapro-... 

In 1929, Dam was studying the role of cholesterol in the diet. For that purpose he prepared a diet extracted with ether. When such a diet was administered to chicks, they developed hemorrhagic diathesis. Dam clearly demonstrated that the hemorrhagic diathesis did not result from the absence of cholesterol, vitamin A, vitamin D, or vitamin E, and he postulated the existence of a new liposoluble vitamin— vitamin K. Dam s finding was confirmed in many laboratories, and the vitamin was concentrated from a number of natural sources. 

Contrary to the predictions in 1989 (27), LC-MS has not experienced a breakthrough as an analytical technique in the vitamin E area. One research group reported two studies on the determination of liposoluble vitamins in foods and infant formulas by LC-particle beam MS (44,50). Caimi and Brenna coupled HPLC with combustion isotope ratio mass spectrometry for the analysis of mixtures of liposoluble vitamins, including a- and y-tocopherol (171). 

There are many factors that lower nutrient availability in packaged and stored foods. Environmental factors such as the presence of oxygen and light, or processing variables such as temperature, time, pH, and oxidizing and reducing agents affect the stability of nutrients like amino acids and vitamins (Borenstein et al. 1990, Harris 1977). Table 17.6 summarizes the susceptibility of hydrosoluble and liposoluble vitamins to these factors. 

After-shave products tend to contain astringent substances (e.g. hamamelis extract, ethanol), refreshing (e.g. menthol), moisturizing or soothing (e.g. aloe vera extract), anti-microbiaL etc. Pre-shave products are similar but tend to contain oils (almond, peanut, safflower) to lubricate the skin and sometimes liposoluble vitamins (A, E) that soften the skin. 

Although vitamins have different structures, sources, requirements, and mechanisms of action, they are classified according to their solubility in water or in fats. Vitamins A, D, E, and K are liposoluble, whereas the B-complex (Bi, B2, Bg, B12, niacin, pantothenic acid, biotin, and folic acid) and C vitamins are hydrosoluble. Moreover, there are some organic compounds related to vitamins that are usually classified with the B vitamins and are also hydrosoluble i.e., p-aminobenzoic acid is included among these substances with similarities to vitamins. 

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