Palmitic acid, 439 Table

Cardamom seeds also contain fixed oils, which are constituted mainly by oleic and palmitic acids (Table 3.11). The non-saponifiable fraction consists mainly of waxes (n-alkanes and... 

Fats are the glyceryl esters of fatty acids. Glycerol is the trihydroxy alcohol CH2OH—CHOH—CH>OH (Section 13-3). It combines with three molecules of a fatty acid, such as palmitic acid (Table 13-3), to produce a fat ... 

In essence, this series of four reactions has yielded a fatty acid (as a CoA ester) that has been shortened by two carbons, and one molecule of acetyl-CoA. The shortened fatty acyl-CoA can now go through another /3-oxidation cycle, as shown in Figure 24.10. Repetition of this cycle with a fatty acid with an even number of carbons eventually yields two molecules of acetyl-CoA in the final step. As noted in the first reaction in Table 24.2, complete /3-oxidation of palmitic acid yields eight molecules of acetyl-CoA as well as seven molecules of FADHg and seven molecules of NADFI. The acetyl-CoA can be further metabolized in the TCA cycle (as we have already seen). Alternatively, acetyl-CoA can also be used as a substrate in amino acid biosynthesis (Chapter 26). As noted in Chapter 23, however, acetyl-CoA cannot be used as a substrate for gluco-neogenesis. 

Table 11.2 Transmethylation yield ofazelaic and palmitic acids using TMAH solution in combination with 610°C Curie point Py GC/MS [12]...

Table 9 Monolayer stability limits of palmitic acid/stearoylserine methyl ester films at 25°C.

As shown in Table 1, the acyl moiety of cardiolipin is comprised almost entirely of unsaturated fatty acids. Other membrane phospholipids such as phosphatidyl choline and phosphatidyl ethanolamine contain 1(M0 mol of saturatedfatty acids such as palmitic acid (Ci6 0) and stearic acid (Ci8 0) per 100 mol of total fatty acids. In particular,linoleic acid (Cl8 2) is the most abundant polyunsaturated fatty acid consisting of 80 mol%, linolenic acid (Cl8 3) 8 mol%, and oleic acid (Ci8 i) 6 mol%. Therefore, by using a commercially available cardiolipin purified from bovine heart mitochondria, we characterized auto-oxidation products by reverse phase HPTLC and reverse phase HPLC. 

Some plants produce a mixture of fatty acids (Table 11.3). The fat in seeds of the cacao tree (Theobroma cacao) contains a mixture of stearic and palmitic acids. The fat is known as cocoa butter from its resemblance to the butter produced from cow s milk (see Box 11.2). 

The main radiopharmaceuticals labelled with fluorine-18, routinely prepared ([2-i F] fluorodeoxyglucose [ F]FDG [26-28], [i F]fluoro-L-DOPA [29], [i F]altanserin [30, 31], [ F]setoperone [32]) are presented with their uses in Table 2. For comparison, the most common tracers labelled with carbon-11 (methionine [33], palmitic acid [34], flumazenil (RO 15.1788) [35], PK 11195 [36], raclopride [37], deprenyl [38], Way-100635 [39], McN-5652Z [40], CGP 12177 [41]) are shown in Table 3. By far, [ F]FDG is the most widely studied, particularly in oncology for the diagnosis of tumours, detection of sub-clinical diseases, assessment of therapy responses, and detection of recurrence. F-Steroids [42], F-proteins or peptides, or F-labelled tissue specific agents have also been synthesized for the detection and monitoring of various malignancies [43]. 

As discussed for N-myristoylation and S-prenylation, even S-acylation of proteins with a fatty acid which in the vast majority of cases is the C16 0 palmitic acid, plays a fundamental role in the cellular signal-transduction process (Table l). 2-5 14 While N-myristoylation and S-prenylation are permanent protein modifications due to the amide- and sulfide-type linkage, the thioester bond between palmitic acid and the peptide chain is rather labile and palmi-toylation is referred to as a dynamic modification. 64 This reversibility plays a crucial role in the modulation of protein functions since the presence or absence of a palmitoyl chain can determine the membrane localization of the protein and can also be used to regulate the interactions of these proteins with other proteins. Furthermore, a unique consensus sequence for protein palmitoylation has not been found, in contrast to the strict consensus sequences required for N-myristoylation and S-prenylation. Palmitoylation can occur at N- or C-terminal parts of the polypeptide chain depending on the protein family and often coexists with other types of lipidation (see Section 6.4.1.4). Given the diversity of protein sequences... 

The lipid of morama beans is mainly ( 75%) unsaturated fatty acids, with the principal fatty acid being oleic acid (43%). The beans furthermore contain linoleic (22%) and palmitic acid (13%) as well as stearic, arachidic, linolenic, arachidonic, erucic, behenic, myristic, palmitoleic, and gadoleic acid in lower concentrations (Bousquet, 1982 Bower et ah, 1988 Engelter and Wehmeyer, 1970 Francis and Campbell, 2003 Ketshajwang et ah, 1998 Mitei et ah, 2008). The fatty acid composition resembles that of olive oil (Mitei et ah, 2008). A literature review of the fatty acid composition of morama beans is given in Table 5.3. Less than 5% of the fatty acids are present as free acids (Bower et ah, 1988 Dubois et ah, 1995), which means that the activity of lipases is negligible in dry morama beans. 

It was necessary to add over 10% buffer for the transesteiification of phosphatidyl choline by native lipase (5). Hydrolysis occurred as a side reaction in the hydrophobic solvent-water system. Tlie transesterification of phosphatidyl choline and eicosapentaenoic acid (EPA) was carried out in water-saturated n-hexane using palmitic acid-modified lipase. Table II shows the transesterification of phosphatidyl choline and EPA. Modified lipase made it possible for the transesterification of phospholipids in organic solvents. 

Ester synthesis of cholesterol linoleate. Cholesterol fatty acid ester is an important cell membrane lipids and has many applications in cosmetics, pharmaceutical and other industries. Akehoshi et aL(7) reported the ester synthesis of the cholesterol fatty acid ester with native lipase. Synthesis of the cholesterol fatty acid ester was also carried out in water-saturated n-hexane by palmitic acid-modified lipase. As shown in Table III, this system made it possible for the synthesis of the cholesterol fatty acid ester in organic solvents using the modified lipase. 

The results of plotting log k8 at constant it as a function of pH for sulfate, phosphonate, and carboxylate films are shown in Figure 5, and the values of A log kjApH are given in Table III. Except for palmitic acid between pH 5.8 and 7.2, A log k8/ApH values for the films were significantly less than predicted by Equation 13. Moreover, the values increasingly deviate from Equation 13 with increase in pH. 

As can be seen in Table 4.2, the fatty acids are not randomly distributed among the three positions of the TG in bovine milk. Control of esterification is not understood, but there are several factors known to affect it. The presence of glucose is known to stimulate the synthesis of milk TG (Dimmena and Emery 1981 Rao and Abraham 1975). In the mouse, Rao and Abraham concluded that glucose was supplying factors other than NADPH or acylglycerol precursors that stimulated milk fat synthesis. The fatty acid that is esterified is known to be affected by the concentration of the acyl donors present (Marshall and Knudsen 1980 Bickerstaffe and Annison 1971). However, in studies under various conditions, palmitic acid was consistently esterified at a greater rate than other fatty acids (Bauman and Davis 1974 Moore and Christie 1978 Smith and Abraham 1975). 

Here R, and R2 are long, fatty acid side chains. The parent fatty acids RjC02H and R2C02H usually have an even number of carbon atoms 16- and 18-carbon acids are the most common. The acid esterified to the hydroxyl group on C-l of the glycerol (that at the top of phosphatidylcholine is drawn above) usually has a fully saturated chain, whereas the acid attached at C-2 often has one or more double bonds, which are almost always cis double bonds. Table 17.1 lists some of the fatty acids commonly found in these positions. A phosphatidylcholine that has palmitic acid esterified at both the C-l and C-2 positions of the glycerol is known by... 

Spermaceti, a fragrant substance isolated from sperm whales, was a common ingredient in cosmetics until its use was banned in 1976 to protect the whales from extinction. Chemically, spermaceti is cetyl palmitate, the ester of palmitic acid (see Table 24.3) with cetyl alcohol (the straight-chain Cjg alcohol). Show the structure of spermaceti. 

There are two isomeric fat molecules whose components are glycerol, one palmitic acid, and two stearic acids (see Table 24.3). Draw the structures of both, and explain how they differ. 

Results of chemical analysis showed that the glucosamine and total fatty acid contents of the KDO depleted, toxic lipid A and the nontoxic lipid A were essentially the same but that the nontoxic lipid A was significantly lower in the phosphorus content (Table V). The molar ratio of glucosamine phosphorus fatty acids was 2 2 4 for the toxic lipid A and 2 1 4 for the nontoxic lipid A. The relative molar distribution of normal fatty acids (lauric, myristic, and palmitic acids) and the 3-hydroxymyristic acid did not indicate a correlation between the content of these components and toxicity. The nontoxic lipid A possessed as high a tumor regression activity when combined with CWS as did the purified... 

It is important to bear in mind when discussing the effect of dairy fat in association to heart disease that dairy products contain many different saturated fatty acids that do not exert the same biological response in terms of, for example, cholesterol levels. The saturated fatty acids in milk fat include shorter and medium chain fatty acids (2 0-10 0), lauric acid (12 0), myristic acid (14 0), palmitic acid (16 0), and stearic acid (18 0). Other fatty acids in milk fat are oleic acid (18 1) and linoleic acid (18 2n-6) as indicated in Table 1.2. 

The GC-MS pattern of fruit volatile oil of star anise (7. vemm Hook) shows the presence of 25 components, which account for 99.9% of the total amount (Padmashree et al., 2007). The major components are trans-anethole (93.9%), estragole (1.05%) and limonene (1.05%) (Table 17.3). Fifteen components are identified from its acetone extract, accounting for 80.27% of the total amount. frans-Anethole (51.81%) is found as a major component, along with linoleic acid (11.6%), l-(4-methoxyphenyl)-prop-2-one (6.71%), foeniculin (5.29%) and palmitic acid (1.47%). 

Among fatty acids, linoleic acid was the major constituent (nearly 50%), followed by oleic ( 24%) and palmitic acids ( 15%). Table 20.4 gives the fatty acid composition of the seed oil of tamarind. Among sterols, betasitosterol constituted 66-72%, followed by campesterol (16-19%) and stigmasterol (Andriamanantena et al., 1983). 

Calcium soaps of palm oil fatty acids are used widely as an energy supplement. With a content of 45 to 50% Ci6 o, these calcium soaps increase palmitic acid in milk fat compared with oilseeds (Table 2.2). Whole oilseeds (cottonseed, canola, soybeans) also are used widely as energy supplements in dairy diets. All except cottonseed oil (25% Ci6 o) contain predominantly Qx fatty acids. When fed whole or crushed, the oil tends to be released slowly,... 

We decided to focus our attention on de novo fatty acid biosynthesis based upon our observations and those reported in the literature (12). To determine whether fatty acid biosynthesis was inhibited, we determined the effect of the herbicides on incorporation into palmitic (16 0) acid, the first product of fatty acid biosynthesis. Maize leaf discs were incubated for 40 min in 14C -acetate, after which fatty acids were extracted. As shown in Table II, both tralkoxydim and haloxyfop significantly reduced the amount of acetate incorporated into palmitic acid. Thus, these compounds affected a step early in lipid biosynthesis. 

Table II. The Effect of Tralkoxydim and Haloxyfop on C-Acetate Incorporation into Palmitic Acid in Maize Leaf Discs...

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