Peanut sterol

Peanuts contain -sitosterol, campesterol, stigmasterol, A5-avenasterol, A7-stigmasterol, A7-avenasterol, andbrassicasterol (Table 8.6). These sterols, which are secondary alcohols with 27-29 carbon atoms, are crystalline solids at room temperature. (i-Sitosterol, the major component in peanut sterols, has been shown to inhibit cancer growth (Awad el al. 2000) and may offer protection from colon, prostate and breast cancer. Unrefined peanut oil contains approximately... 

It is claimed (Youk et al., 1999) that olive, sunflower and peanut oils contain mainly esterified sterols, while soyabean and sesame oils contain mainly free sterols. This does not appear to have been utilized previously, but could be useful with mixtures of the two classes. Although it is possible to de-sterolize oils, and remove characteristic sterols, this usually forms other sterols that can be detected (Biedermann and Grob, 1996 Lanuzza and Micali, 1997 Mariani and Venturini, 1997). If it is suspected that this has occurred, then the presence of other suspect components should be investigated. 

Sterol Coconut Corn Cotton Seed Linseed Olive Pam Palm Kernel Peanut Rape Seed Rice Bran Saf- flower Sesame Shea Butter Soy Bean Sun flower Wheat Germ... 

High aliphatic alcohols and wax esters in which aliphatic alcohols or sterols are esterified to fatty or phenolic acids are also present in cmde vegetable oils at low levels and are partially removed in the winterization process during oil refining. Waxes, mainly esters of long-chain saturated fatty acids and a monounsaturated alcohol, especially eicosenoic alcohol, are found in crude vegetable oils such as olive, sunflower, soybean or peanut but are absent from com or rice bran oils... 

The unsaponifiable matter of soy, corn, canola/rapeseed, sunflower, cottonseed, peanut, and palm ranges from 10-30%, and it is composed of 40% phytosterols and 15% tocopherols (199-202). The temperature, duration, quantity of skimming vapor, and the extent of vacuum used for deodorization are the parameters that greatly influence the quality and quantity of DOD. The low content of tocopherols and sterols in the DOD often requires a concentration step however, if the starting material is soybean, this is not an issue because of the high concentration of these compounds. 

Table III gives the physical and chemical properties of the M. oleifera oil. Some of the properties of the oil depend on the extraction medium. The M oleifera oil is liquid at room temperature and pale-yellow in colour. Electronic nose analysis shows that it has a flavor similar to that of peanut oil. The melting point estimated by differential scanning calorimetry is 19°C (15). The chemical properties of the oil depicted in Table III below are amongst the most important properties that determines the present condition of the oil. Free fatty acid content is a valuable measure of oil quality. The iodine value is the measure of the degree of unsaturation of the oil. The unsaponifiable matter represents other lipid- associated substances like, sterols, fat soluble vitamins, hydrocarbons and pigments. The density, iodine value, viscosity, smoke point and the colour of Moringa oil depends on the method of extraction, while the refractive index does not. Varietal differences are significant in all physical characteristics apart from refractive index and density (2). The heating profile of the M. oleifera seed oil using the differential scanning calorimetry (DSC) conventional scan rate shows that there is one major peak B and, two small shoulder peaks A and C...

Table 8.6 Sterol content of unsaponifiables of peanut oil and whole peanuts...

The unsaponifiable matter in peanut oil is mainly sterols (largely fi-sitostcrol and campesterol). 

Worthington, R.E. and Hitchcock, H.L. (1984) A method for the separation of seed oil steryl esters and free sterols Application to peanut and corn oils. J. Am. Oil Chem. Soc., 61, 1085-1088. 

Ortho Spotkss. [ vton] Diniconazole systenric, sterol-inhibiting fungicide for use on peanuts, qqdes, grq)es, small grains, etc. 

For example, the total sterol content of mycelium of the peanut leafspot pathogen Cercospora arachidicola treated with 0.1 ppm of propiconazole is 1.5 ug/mg dry weight, 80% of which is C-14 methyl sterols, compared to 0.7 ug/mg in non-treated mycelium, (42). The ergosterol content is reduced 50% on a dry weight basis by treatment with the inhibitor. This increase in total sterol may be due to a reduction in feedback inhibition of sterol biosynthesis by ergosterol or one of its metabolites. However, the increase in total sterol does not occur in some fungi (e.g. cerevisiae). 

Olive oil is often illegally adulterated with other less expensive vegetable oils. Oils widely used for this purpose include olive pomace oil, corn oil, peanut oil, cottonseed oil, sunflower oil, soybean oil, and poppy seed oil. °° Among the varions chemical and physical methods employed toward the detection of the adulteration of olive oil by low-grade olive oils and seed oils are (a) Sterol analysis (presence of stigmasterol and 3-sitosterol), (b) alkane analysis (C27, C29, and C31), (c) wax and aliphatic alcohol analysis, (d) fatty acids/(with HPLC) trans fatty acid, and (e) Triacylglycerol. 

Plant and animal N.f. can be distinguished analytically because they are associated with different sterols, e. g. phytosterol in plant fat and cholesterol in animal fat. They are of equal nutritional value, however, provided that the same vitamins and essential fatty acids are present. Plant N.f. are most abundant in seeds (40-45 % in rapeseed, poppy seed and linseed). Olives contain up to 25% N.f. The most important fruit oils are palm and olive oils the most important solid seed N. f. are coconut and palm seed fats and cocoa butter. The seed oils of cotton, com, sunflowers, peanuts, soy, almonds, sesame, flax (linseed), poppies, rape, mustard and Ricinus are economically important. 

Awad AB, Chan KC, Downie AC, Fink CS (2000) Peanuts as a source of P-sitosterol, a sterol with anticancer properties. Nutr Cancer 36(2) 238-241... 

Antioxidative compounds from oilseeds such as canola/rapeseed, mustard, flax, borage and evening primrose, soybean, cottonseed, peanut and sesame have been investigated. The antioxidative conq)onents present are diverse and may end up in the extracted oil or in their resultant meal after oil extraction. The antioxidative compounds present include tocopherols, sterols, phospholipids, phenolic acids and phenylpropanoids, flavonoids and isoflavonoids, hydrolyzable and condensed tannins, lignans, coumarins, amino acids, peptides and proteins as well as carotenoids (7). 

Among other sterols revealed in the past, are fucosterol in the Asphodelus fistolosus oil (Khan et al., 1961) and spinasterol in spinach oil (Larsen, 1938). Palm oil contains, in addition to campesterol, stigmasterol and jS-sitosterol, a fourth component whose retention time in GLC is very close to that of cholesterol (Recourt and Beerthuis, 1963). Cholesterol seems also to be a minor sterol of peanut oil (Walbecq, 1966). Definitive proofs of its identity are still lacking. 

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