Tocopherols important sources

Sensidoni, A., Bortolussi, G., Orlando, C. and Fantozzi, P. (1996) Borage oil (Bortago officinalis L.) an important source of gamma linolenic acid. II. Tocopherols and chlorophyll content and sensorial analysis of borage oils extracted by different techniques and blended with extra virgin olive oil. lnd. Aliment., 35, 664-669. 

The tocopherol and tocotrienol contents of selected vegetable oils are shown in Table (7). Seed oils are mostly dominated by y- or a-tocopherol, but high levels of 5-tocopherol especially characterize soybean oil, which is the richest and commercially the most used source of tocopherols (46). Rice bran and pahn oils, on the other hand, represent the important sources of tocotrienols (45, 47). Rapeseed... 

Oils and Cereals as Important Sources of Tocopherols and Tocotrienols... 

Soybean oil is the most important source of vitamin E in the Western world. It contains, on average, 1000 pg/g of tocopherols (Eitenmiller, 1997 Kamal-Eldin and Andersson, 1997). The total tocopherol contents of 14 breeding lines with commodity-type fatty acid composition were 1406-2195 pg/g, while those of the major isomers y-, 8- and a-tocopherols were 850-1171, 254-477 and 44-158 pg/g, respectively (Dolde et al., 1999). 

Palm fatty acid distillate (PFAD) is a valuable by-product of palm oil processing, from which the production of tocopherols and tocotrienols is technically feasible (Ong and Choo, 1997). PFAD is wildly abundant, as palm oil is the second largest oil produced in the world. It contains 4000-8000 pg/g total vitamin E compounds, which is up to 10 times as much as crude palm oil contains (Tan, 1989 Ong and Choo, 1997). The tocopherol and tocotrienol profiles of PFAD and crude palm oil are similar, consisting of about 85% of tocotrienols, i.e., y-tocotrienol > a-tocotrienol > 8-tocotrienol (Tan, 1989). Because of cholesterol-lowering properties (Lane et al., 1999), the high level of tocotrienols makes PFAD an important source, because most other natural sources are devoid of tocotrienols. Fatty acids and esters, sterols and squalene are removed from PFAD as described above. Finally, the vitamin-E-rich product is purified and deodorized to yield a tocopherol/tocotrienol-rich product of 95-99% purity. 

Oil extracted from rice bran and com fiber is especially rich in tocopherols, tocotrienols and sterols. Extraction of these valuable compounds is remarkably enhanced by heat pretreatment (Lane et al., 1999). For example, the level of extracted y-tocophcrol increased from 0.3% to 3.6% by subjecting com fiber to temperatures of 100-175°C (Moreau et al., 1999). Tocopherol- and tocotrienol-rich oils may be used as such as important sources of vitamin E, or the vitamers can be purified from them following the same protocols as above. 

Both phytosterols and tocopherols are co-extracted with oil and partially removed during soybean oil refining. The refining by-product is one of the important sources for commercial phytosterol and tocopherol production. 

Plant lipids increase the nutritional value of food they contain more essential FA than animal fats. They also contain tocopherols and tocotrienols, which are the most important sources of vitamin E. A disadvantage is that plant lipids (similar to animal fats) considerably increase the content of available energy. Therefore, the consumption of fried foods should be restricted because they are rich in fat. 

Phenolics are ubiquitous secondary metabolites that are widely distributed in the plant kingdom. They play a very important role in plants and are one of the most important sources of plant bioactives in the human diet [26]. Phenolic compounds ntight participate in the prevention of various diseases associated with oxidative stress [27,28]. Tocopherols are the major phenolics identified in Brazil nut, thus more research is needed to determine other phenolics present in Brazil nut. This work is currently under investigation in onr laboratories. 

The quaHty, ie, level of impurities, of the fats and oils used in the manufacture of soap is important in the production of commercial products. Fats and oils are isolated from various animal and vegetable sources and contain different intrinsic impurities. These impurities may include hydrolysis products of the triglyceride, eg, fatty acid and mono/diglycerides proteinaceous materials and particulate dirt, eg, bone meal and various vitamins, pigments, phosphatides, and sterols, ie, cholesterol and tocopherol as weU as less descript odor and color bodies. These impurities affect the physical properties such as odor and color of the fats and oils and can cause additional degradation of the fats and oils upon storage. For commercial soaps, it is desirable to keep these impurities at the absolute minimum for both storage stabiHty and finished product quaHty considerations. 

Lipids are important components of the diet fatty acids are the higher energetic source as they ensure 9kcal/g. Furthermore, some peculiar fatty acids themselves and several components of the unsaponifiable fraction are biologically active molecules, as they can act as vitamins (tocopherols— vitamin E), provitamins (carotenes—vitamin A, cholecalcipherol—vitamin D), vitamin-like (essential fatty acids), and hormones or hormone precursors (sterols—steroidal hormones). 

Vitamin E is required for normal growth and reproduction. The most important natural source is a-tocopherol found in plant oils and seeds. The ester form (e.g. vitamin E acetate) can be synthesized and is used for feed supplementation. One international unit is defined as being equivalent to the activity of 1 mg DL-a-tocopherol acetate. The nutritional role of vitamin E is closely interrelated with that of selenium and is involved mainly in the protection of lipid membranes such as cell walls from oxidative damage. Although these signs are similar to those of selenium deficiency, it is not possible to substitute selenium completely for vitamin E. Both nutrients are required in the diet. 

The supply of palm oil has risen considerably since around 1980. It was almost 24 million tons per annum in 2001-2002 and is predicted to exceed the production of soybean oil during the period 2011-2015 at around 37 milhon tons. The oil contains almost equal proportions of saturated (palmitic 48% and stearic 4%) and unsaturated acids (oleic 37% and hnoleic 10%). The major triacylglycerols are POP (30-40%) and POO (20-30%). The oil is used mainly for food purposes but finds some nonfood uses. It is a source of valuable byproducts such as carotene and tocopherols and tocotrienols (vitamin E). Red palm oil is a carefully prepared oil that retains about 80% (500-700 ppm) of the carotenes present in the crude oil and is a valuable dietary source of these important compounds (42). 

Ascorbic acid and tocopherols are the most important commercial natural antioxidants. In addition, many naturally occurring phenolic antioxidants have been identified in plant sources and vegetable extracts that may lend themselves for use in a variety of food applications (53). Recent research has focused on isolation and identification of effective antioxidants of natural origin (11). 

With the increasing interest in natural source antioxidants, such as tocopherols, and the use of both stigmasterol and (3-sitosterol as raw materials for the production of progesterone and esterone by the pharmaceutical industry, it is likely that deodorizer distillates will continue to be an important by-product for some vegetable oil processors. 

Good sources of vitamin E are vegetable oils, such as com, soy, and peanut oii. Animal fats, such as butter and lard, contain lowrer amounts of the vitamin. The content of the most important form of vitamin E, a-tocopherol, in various foods is as follows. Com oil contains about 16 mg of a-tocopherol per 100 g sunflower oil 50 mg/100 g, wheat germ oil 120 mg/100 g and fish, eggs, and beef 0.5 to 2,0 rng/100 g. In plants, a-tocopherol resides in chloroplasts, while other forms of tocopherol ( i-, y-, and 5-tocopherol) occur elsewhere in the plant cell. Tocotrienols, which also have vitamin E activity, are not found in the green parts of plants, but in the bran and germ of seeds... 

One common feature of the mediterranean dietary habit is the use of olive oil as fat source in place of animal fat typical of Northern European and USA diets. As compared to other vegetable oils, olive oil is charaeterized by the peculiar composition of the tryglieeride fraction and by the phenolic and volatile constituents which affect the organolectic properties. Olive oil is rich in monounsaturated fat (56-84% of oleic acid), contains 3-21% of the essential linoleic aeid [3], is low in tocopherols [4,5] and therefore the presence of phenols is important to mantain the anti-oxidative stability. Several articles [1,2,6] reviewed the reasons why olive oil should be preferable to other dietary fat, paying particular attention to the fatty acid composition. Oleic acid is antithrombotic compared to saturated fatty acids [7]. Monounsaturated and polyunsaturated fats reduced low density lipoproteins (LDL) levels. 

R)-(+)-C1tronella1 Is a useful, key Intermediate for the preparation of several Important, optically active compounds such as citronellol, 1-menthol, muscone, and a-tocopherol The optical purity of citronellal from natural sources is at most 11% ee, however. This new procedure gives (R)-(+)-citronellal of high optical purity (over 95% ee). 

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