Lipid unsaponifiable

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). 

Sterols. These compounds are found in the unsaponifiable fraction of milk lipids and consist mostly of cholesterol with some lanosterol. Methods for the determination of unsaponifiables using dry saponifica-... 

Flanagan, V. P. and Ferretti, A. 1973. Hydrocarbons and polychlorinated biphenyls from the unsaponifiable fraction of anhydrous milk fat. J. Lipid Res. 14, 306-311. 

Recently, however, prepacked solid-phase extraction (SPE) columns have been preferred. In this case, too, the phospholipid fraction is often recovered by elution with methanol. Thus, Nash and Frankel developed a method to recover the phospholipids from 1-g portions of crude oils using silica gel Sep-Pak cartridges (29). The oil was applied as a 10% solution in a 95/5 (v/v) mixture of petroleum ether and diethyl ether, and neutral lipids (about 94-97%) were eluted with 10 ml of additional solvent the so-called unsaponifiables (2-3%) were recovered using 20 ml of diethyl ether, and the phospholipid fraction was obtained using 10 ml of methanol. 

Sato, Y. and Tsuchiya, Y. (1970). Studies on the lipids of Ruvettus pretiosus. n. The composition of the unsaponifiable material and die purgative action of the oils on die mouse. Tohoku Journal of Agricultural Research 21,176-182. 

Other extraction methods used in the lipid extraction include supercritical fluid extraction (SFE) and pressurized liquid extraction (PLE). With SEE, good extraction yields have been obtained for nonpolar lipids including ester-ified fatty acids, acylglycerols, and unsaponifiable matter. However, complex polar lipids are only sparingly soluble in supercritical carbon dioxide alone and polar modifiers, such as methanol, ethanol, or even water is required to improve the extraction of polar lipids (10). SFE has been used for the extraction of lipids especially from various food matrices, such as different nuts, edible oils, and seeds (11). The recoveries of lipids in SFE were on the same levels than with conventional solvent extraction methods (12,13), no significant differences between the fatty acids extracted were observed. PLE has also been used in lipid extraction, although only in very few applications (14). The elevated temperatures used in PLE can cause alteration of the lipid composition. 

Unsaponifiable lipids of Cotugnia digonopora and Raillietina fuhrmanni. (Cestoda Cyclophyllidea). Folia Parasi-tologica, 27 59-61. 

Gutfinger, T. and Letan, A. (1974) Studies of unsaponifiables in several vegetable oils. Lipids, 9,658-663. 

Moisture, impurities, and unsaponifiables (MIU) A summation of the non-acylglycerol materials in the product. Moisture is undesirable because it will support microbial growth and facihtate hpid hydrolysis. Unsaponifiables are any materials that will not saponify (form soap) when incubated with sodium hydroxide. These include sterols, pigments, and hydrocarbons. These are natural components of both animal and plant lipids, but excessive amounts can indicate a sample that will not perform comparably with a sample richer in acylglycerols, and they can indicate adulteration or contamination by petroleum products. 

Avocado Persea americana). The avocado grows in tropical and subtropical countries between 40°N and 40°S and is available particularly from California, Florida, Israel, New Zealand, and South Africa. Like the palm and the olive, lipid is concentrated in the fruit pulp (4—25%) from which it can be pressed. There is very little oil in the seed (2%). The oil is used widely in cosmetic products as it is easily absorbed by the skin, and its unsaponifiable material is reported to provide some protection from the sun. It is also available as a high-oleic speciality oil for food use. It is rich in chlorophyll, making it green before processing. It contains 16 0 (10-20%), 18 1 (60-70%), and 18 2 (10-15%) as its major fatty acids. Its unsaponifiable matter, total sterol, and tocopherol levels have been reported (74-78). 

The sterols found in the unsaponifiable fraction of milk lipids are mostly cholesterol esters, small quantities of lanosterol, and even smaller quantities of two new constituents dihydrolanosterol and p-sitosterol (33). 

TABLE 17. Effect of Daily Addition of Rice Bran Unsaponifiables (RBN) on Serum Lipids (mmol/L) in Hypercholesterolemic Subjects (54). ... 

Edible fats and/or oils, or mixtures of these, whose origin is vegetable or rendered animal carcass fats or any form of oil from a marine species that has been affirmed as GRAS or listed as a food additive for this use, any or all of which may have been subjected to an accepted process of physico-chemical modification. They may contain small amounts of other lipids such as phosphatides, or unsaponifiable constituents and of free fatty acids naturally present in the fat or oil. 

Calcium salts of long-chain fatty acids (33.14) are the reaction products between calcium and long-chain fatty acids of vegetable and/or animal origin. They shall contain a maximum of 20% lipid not bound in the calcium salt form and the percent total fat shall be indicated. The unsaponifiable matter (exclusive of calcium salts) shall not exceed 4% and moisture shall not exceed 5%. If an antioxidant is used, its common name must be indicated on the label. Before conducting an assay for total fats, hydrolysis of the calcium salts should be performed to liberate the lipid fraction. 

Squalene and phytosterols are components present in the unsaponifiable lipid fraction of foods (as tocopherols). Squalene is an intermediary in cholesterol biosynthesis, and 33.9-58.4 mg/100 g of it was found in the lipid fraction of quinoa (Jahaniaval et al., 2000 Ryan et ah, 2007) squalene is the biochemical precursor of the whole family of steroids, and besides their effective antioxidant activity, tocotrienols have other important functions, in particular in maintaining a healthy cardiovascular system and a possible role in protection against cancer (Nesaretnam, 2008). Squalene is used as a bactericide and as an intermediate in many pharmaceuticals, organic coloring materials, rubber chemicals, and surface-active agents (Ahamed et ah, 1998). 

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...

Oil recovered by solvent extraction or mechanical pressing is termed crude soybean oil and contains various classes of lipids. It consists primarily of neutral lipids, which include tri-, di- and monoacylglycerols, free fatty acids, and polar lipids such as phospholipids. It also contains a minor amount of unsaponifiable matter that includes phytosterols, tocopherols, and hydrocarbons such as squalene. Trace metals are found in soybean oil in ppm concentration. When the oil is refined, concentrations of all minor constituents are reduced. The typical composition of crude and refined soybean oil is shown in Table 2.2. 

Heat of fusion (unhydrogenated) Refractive index (n ) 40°C) Unsaponifiable lipids... 

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