Major fatty acids stearic

Despite the large variety of potential fatty acid components in natural-occurring phosphodiglycerides, only three major fatty acid derivatives of synthetic phospholipids are commonly used in liposome preparation (1) myristic acid (w-tetradecanoic acid containing 14 carbons), (2) palmitic acid (w-hexadecanoic acid containing 16 carbons), and (3) stearic acid (w-octadccanoic acid containing 18 carbons) (Fig. 334). 

Fatty acids and sphingosines. The lipid composition of the four monosialogangliosides is shown in Table II. The major fatty acids are palmitic, stearic and oleic acids. The long chain base is composed mainly of C-18 sphingosine with less than 20% of dihydrosphingosine. 

Fatty acids are the building blocks of TAG. More than 90 percent of fatty acids have an even number of carbon atoms, and are in aliphatic chains ranging from 4 to 22 carbons in length. The major fatty acid synthesis pathway is production of stearic acid (18 carbons) after which separate desaturase systems introduce 1, 2, or 3 unsaturated (double) bonds. Additional enzymes become active in elongating the chain as needed. Shorter fatty acids also are produced. Trace amounts of odd-number carbon fatty acids are found in most fats, and also have been synthesized for research purposes. Microorganisms frequently produce odd-number carbon fatty acids, with heptadecenoic (17 carbon) acid a major component of Candida tropicalis yeast fat. Up to 8 percent C17 fatty acids have been found in milk and meat fats of ruminants (cattle, sheep, goats) and are of rumen microbe origin. 

Ruminant milk fats are characterized by a much greater variety of component fatty acids. Lower saturated acids with 4 to 10 carbon atoms are present in relatively large amounts. The major fatty acids are palmitic, oleic, and stearic. 

Octadecanoic Stearic 69.6 Major fatty acid in animal tissues and some fungi, usually minor in plants, major only in a few plant species (e.g., cocoa butter). 

Cashew (Anacardium occidentale). Toschi et al. (91) have given details of the fatty acids, triacylglycerols, sterols, and tocopherols in cashew nut oil. The major fatty acids are palmitic (9-14%), stearic (6-12%), oleic (57-65%), and linoleic (16-18%), and the major triacylglycerols are OOO, POO, OOSt, OOL, and POL. 

Melon Citrullus colocythis and C. vulgaris). This seed oil has been examined in terms of its fatty acids and phospholipids by Akoh and Nwosu (139). The major fatty acids in the total lipids are palmitic (11% and 12%), stearic (7% and 11%), oleic (10% and 14%), and linoleic acid (71% and 63%) for two samples. 

Sunflower Fatty Acids Regular sunflower oil is characterized by a high concentration of linoleic acid, followed by oleic acid. Saturated fatty acids (mainly palmitic acid and stearic acid) do not amount to more than 15% of the fatty acid content. Table 1 shows the variation range of major fatty acids in regular sunflower oil (9, 20). 

Table 7 shows the fatty acid composition of different citrus seed oils. The ratio of unsaturated to saturated fatty acids is approximately 2 1 (9), although this ratio was reported to be in the range of 3-5 1 by Nagy (35). Generally, different varieties, cultivar, location, storage condition, and harvesting time of citrus fruit may lead to this variation. Table 8 shows the content of the six major fatty acids in different citrus seed oils these are linoleic (C18 2), palmitic (C16 0), oleic (C18 l), linolenic (C18 3), stearic (C18 0), and palmitoleic (C16 l) acids. 

The proximate composition of almond includes 50.6% lipid, 21.3% protein, 19.7% carbohydrate, 5.3% water, and 3.1% ash (w/w) (1). The most common method for producing almond oil is hexane extraction that affords high oil yields, however, cold pressing is another commercially used procedure for almond oil production (8). Shi et al. (8) assessed the fatty acid composition of almond oil oleic acid was major fatty acid present (68%), followed by hnoleic acid (25%), palmitic acid (4.7%), and small amounts (<2.3%) of palmitoleic, stearic, and ara-chidic acids (Table 1). Almond oil is also a rich source of a-tocopherol (around 390 mg/kg) and contains trace amounts of other tocopherol isomers as well as phyl-loquinone (70pg/kg) (1). Almond oil contains 2.6g/kg phytosterols, mainly p-sitosterol, with trace amounts of stigmasterol and campesterol (1). 

Colocynthis citrullus seed oil and found that it contained a relatively high percentage of linoleic acid that accounted for 57.7% of total fatty acids (Table 4) (26). Oleic acid was the second major fatty acid (14.5%). The seed oil contained about 25.3% saturated fatty acids (Table 4). Moussata and Akoh (27) also reported a similar fatty acid profile of Colocynthis citrullus L. seed oil. The primary fatty acid was linoleic acid, contributing 65.4% of total fats. The other significant fatty acids included oleic (13.5%), palmitic (12.1%), and stearic (9.0%) acids (Table 4). 

Mango seed kernels contain about 4-12% total fat (45 7). Mango seed kernel oil is rich in oleic acid (Table 7), and exhibited 42% (47), 34—59% (45), and 41 )4% of total fatty acids (46). Stearic acid is the other major fatty acid in mango seed kernel... 

The cherry tree Prunus avium L.) is a member of the Rosaceae family. Cherry seed contains about 18% oil on a dry weight basis (48). Significant levels of oleic acid were detected in the cherry seed oils prepared by hexane extraction using a Soxhlet apparatus. Oleic acid comprised 24—38% of the total fatty acids from three different varieties of cherry fruits (Table 7) (48). Linoleic acid was the major fatty acid in the cherry seed oil, and ranged 40 9% in the seed oil, along with ot-eleostearic (18 n-5), palmitic, stearic, arachidonic, and ot-linolenic acids (Table 7). alpha-eleostearic acid comprising 10-13% of cherry seed oil, is a conjugated... 

Literamre equilibrium solubility data of ternary systems of major and minor lipid components, cosolvents, and SCCO2 have been compiled (28), and the effect of cosolvent addition on the solubility behavior of fatty acids (stearic, palmitic, and behenic acids), squalene, and p-carotene studied. Cosolvent effect is quantified as solubility enhancement, which is the ratio of solubihty obtained with cosolvent addition to that without a cosolvent (28). This reference (28) contains an exhaustive bibliography on cosolvent + SCCO2 + lipid systems. 

Com oil is composed of fatty acid esters with glycerol, known commonly as triglycerides. Typical com oil produced in the USA contains five major fatty acids linoleic 58.9% oleic 25.8% palmitic 11.0% stearic 1.7% and linolenic 1.1%. Com grown outside the USA yields com oil with lower linoleic, higher oleic, and higher saturated fatty acid levels. Corn oil also contains small quantities of plant sterols. 

Major fatty acid compositions" (% w/w) Palmitic acid 4.14 Stearic acid 1.57 Oleic acid 35.86 Linoleic acid 19.75 Linolenic acid 7.77 Erucic aicd 12.90... 

Gangliosides are carbohydrate-rich complex lipids (Fig. 5.1). They are a major component of neuronal cells and are essential for brain function. They contain sph-ingosine, fatty acid, and an oligosaccharide chain that vary in size from one to four or more monosaccharides. They are present in the external leaflet of the neural membrane (Shioiri et al., 2009). The hydrophobic moiety of ganglioside consists of sphingosine and fatty acid (stearic acid, 95%). This moiety is inserted into the neural membrane, while the hydrophilic moiety, consisting of sialic acid (NANA) and other carbohydrates, protrudes toward the extracellular fluid. 

In comparison to other vegetable sources, avocado oil is characterized by its contents of palmitic (C16 0), linoleic (C18 2), palmitoleic (16 1) and alpha-linolenic (18 3) FAs that are 13.5, 12.6, 3.26 and 1.0 % of total fatty acids, respectively. Stearic (18 0), tridecanoic (13 0), tetradecanoic (14 0), cA-lO-heptadecenoic (17 1) and c/s-13-16-eicosenoic (20 2) FAs are present in trace amounts [49]. Ozdemir and Topuz [50] showed in Fuerte and Hass avocado varieties present a reduction of palmitc acid according to fruit ripening, with variations of 22.4-12 % to Fuerte variety and 23.3-16.8 % to Hass variety. Yanly et al. [51] studying three Malaysia avocados varieties, found oleic acid as the major fatty acid (43.65-51.22 %) followed by palmitic (26.41-30.37 %) and linoleic (12.75-17.45 %) FAs. Oils of avocado fruits are generally found to have extremely low amounts of stearic acid (0.27-1.56 %). 

Although the number of fatty acids detected in plant tissues approaches 300, most of them only occur in a few plant species (Hitchcock and Nichols, 1971). The major fatty acids are all saturated or unsaturated monocarboxylic acids with an unbranched even-numbered carbon chain. The saturated fatty acids, lauric (dodecanoic), myristic (tetradecanoic), palmitic (hexadeca-noic), and stearic (octadecanoic), and the unsaturated fatty acids, oleic (cis-9-octadecenoic), linoleic (c/5 -9,cw-12-octadecadienoic), and linolenic (all-cij-9,12,15-octadecatrienoic (Table I), together account for almost all of the fatty acid content of higher plants. For example, about 94% of the total fatty acids of commercial oils and 89-97% of leaf fatty acids consist of these seven structures alone. It will be noted that the unsaturated acids all contain a cis-9 double bond and that the polyunsaturated acids contain a methylene-interrupted structure. The four saturated fatty acids differ from each other by two carbons. These structural relationships are due to the principal pathways of fatty acid biosynthesis in plants (see Stumpf, this volume. Chapter 7). 

Bovine milk fat is made up of 97-98 (wt% of total lipids) triacylglycerols accompanied by much smaller amounts of diacylglycerols (0.36%) and monoacylglyc-erols (0.03%), free cholesterol (0.31%), trace amounts of cholesteryl esters, phospholipids (0.60%), and minor amounts of free fatty acids. For reviews of the composition of bovine milk lipids, the reader is referred to Christie (4) and Jensen and Clarke (5). More than 400 fatty acids have been identified in milk fat, although it is generally accepted that 15 major and 12 minor fatty acids dominate the fatty acid spectrum. The major fatty acids found in milk are long chain (Cj. , myristic Ci6-o. palmitic Cjg., stearic Cjg.j, oleic) and the minor fatty acids are short chain... 

Major fatty acids found in Glomales spores were palmitic acid (C16 0), stearic acid (Cl 8 0) and oleic acid (C18 l)(Table 2). A11-16 1 hexadecenoic acid appeared to be present in the majority of Glomales spores analyzed. Found abundantly in 9 of the 12 studied species, it remained absent from Gigaspora margarita, the sole representative of the studied Gigasporaceae. Further investigations with GC-MS would confirm the A11 position of the... 

The dermatitis associated with total EFA deficiency is most likely due to the role of linoleic acid in skin. Linoleic acid is the major fatty acid component of skin ceramides. This sphingolipid functions to prevent water loss through the skin (Simopoulos, 1989). Other fatty acids are not incorporated into skin ceramides to any great extent (Hansen and Jensen, 1985). Linoleic acid is also an efficient source of energy when compared to stearic and oleic acids. This is due to the more rapid oxidation of linoleic acid versus these 18 carbon saturated and mono-unsaturated fatty acids (Dupont, 1988). 

The seed kernel of the chironji (Buchanania lanzan Anacardiaceae) a fruit found in India, Burma and Nepal contains 65.6% oil on a dry weight basis. The kernel oil is used as a substitute for olive and almond oils in India. The major fatty acids are oleic (63.2%), palmitic (33.8%) and stearic acid (2.0%) (Hemavathy and Prabhakar, 1988). 

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