Fatty acids unsaturated, table

Strocchi and Holman (1971), with the aid of argentation TLC and GLC-mass spectrometry, identified the fatty acids in Tables 4.7 and 4.8. We have presented all of their data because the identifications were obtained by unequivocal methods, many previously tentative identifications were confirmed, and the results were quantitative. Strocchi and Holman did not identify the positional isomers of the unsaturates but found two or three peaks for most of the carbon numbers. Iverson (1983) determined the quantities of minor and trace fatty acids, verifying the findings of other investigators. 

One hundred and eighty-one molecular species of TGs have been identified 79 of them were saturated, 44 monounsaturated, and 58 polyunsaturated. The majority of the unsaturated TGs (61) contained only one unsaturated fatty acid, 41 contained two, and 5 had all three fatty acids unsaturated. Furthermore, ten TGs that contained linear or branched odd-carbon-number fatty acids have been identified. In Table 6, identified species are mentioned with retention times and peak numbers corresponding to the chromatogram in Fig. 43. 

Hydroxy fatty acids (HFAs) (Table 4) have hydroxyl functional groups attached to the principal chain, and they can be both saturated and unsaturated. The principal chain can be branched, and these branches are sometimes quite long. 

Table 23.1 lists some of the most common fatty acids, and Table 23.2 gives the fatty acid composition of a number of common fats and oils. Notice that in the unsaturated fatty acids in Table 23.1 the double bonds are all cis. Many naturally occurring fatty acids contain two or three double bonds. The fats or oils that these come from are called polyunsaturated fats or oils. The first double bond of an unsaturated fatty acid commonly occurs between C9 and C10 the remaining double bonds tend to begin with Cl 2 and C15 (as in linoleic acid and linolenic acid). The double bonds, therefore, are not conjugated. Triple bonds rarely occur in fatty acids. 

It is probable that our ancestors of several million years ago developed the characteristics leading to our modem biochemistry by eating animal fats (Crawford and Marsh, 1989 Sinclair and O Dea, 1990 O Dea, 1991). At first glance this should simplify discussion of animal fats, as shown by the basic fatty acids of Table 10.1. A popular shorthand notation is used to indicate the stmctures of common fatty acids. In the format x yn-z, x is the chain length or number of carbons in the chain, y is the number of methylene-interrupted cis ethylenic bonds and z is the inclusive number of carbon atoms from the terminal methyl group to the center of the nearest bond. As few as six fatty acids appear to adequately describe animal depot fats. Those fats listed are dominated by two fatty acids, 16 0 (palmitic) and 18 1 (oleic) add. Although tropical seed oils may be rich in C12-C18 saturated fatty adds (Elson, 1992), temperate oilseeds are rich in oleic acid and tend to include quantities of two fatty acids more unsaturated than oleic, especially 18 2n-6 (linoleic), and sometimes 18 3n-3 (linolenic). Even the original rapeseed (Brassica sp.) oil, with up to 50% of 22 ln-9 (emdc) acid usually had approximately 20% 18 2/1-6 and 10% 18 3/i-3 adds (Ackman 1983, 1990). 

Linolenic acid (Table 10.2) and stearidonic acid are omega-3 fatty acids, unsaturated fatty acids that contain the first double bond located at C3, when numbering begins at the methyl end of the chain. Predict how the melting point of stearidonic acid compares with the melting points of linolenic and... 

The daily requirement is given in Table 6.3. It increases when the diet contains a high content of unsaturated fatty acids (cf. Table 6.5). A normal supply results in a tocopherol concentration of 12 6 pmol/l in blood plasma. 

Saturated and unsaturated hydrocarbons with odd and even numbers of carbon atoms in the molecule (about C11-C35) are present as the primary substances in all vegetable oils and animal fats. Alkanes, alkenes, alkadienes and alkatrienes also arise as oxidation products of unsaturated fatty acids, catalysed by lipoxygenases or by autoxidation of fatty acids during food storage and processing. Only the lower hydrocarbons can play a role as odour-active substances. The main hydrocarbons resulting from oxidation of unsaturated fatty acids are ethane from Hnolenic acid, pentane and butane from Hnoleic acid and hexane and octane from oleic acid. The immediate precursors of hydrocarbons are the fatty acid hydroperoxides (Table 8.4). The unsaturated hydrocarbons are predominantly (Z)-isomers. Numerous other hydrocarbons, including ahcycHc hydrocarbons, appear as secondary hpid oxidation products. 

In order to investigate further the cause and effect relationship between the content of t-16 l and the stability of LHCP oligomer supported by the above observation with salina, thylakoids freshly isolated from 30 C-grown cells were hydrogenated with the PdCQS) catalyst for either 10 or 40 min. There was a rapid and pronounced decrease in the degree of fatty acid unsaturation in all lipid classis, as illustrated by the examples shown in Table 2. 

There was only a 33% increase in cell number in the cultures after incubation for 48 h at 18 0 at the relatively high initial cell density (5.98 X 108 cells/ml), and the plasma membrane-enriched fraction contained vesicles as before. Although the relative amounts of brassicasterol and the C28 diene were essentially the same as in the reference cells, the A/mole increased to 1.24 indicating an increase in the degree of fatty acid unsaturation which involved changes in the relative amounts of palmitic, stearic, oleic and linoleic but not linolenic acids (Table 1). 

The principal changes in the fatty acids composition consist essentially in dropped linolenic acid percentage in favour of oleic and linoleic ones (Table I). This leads to a decreasing fatty acids unsaturation degree when CaCl2 concentration is increasing. 

Seed oils contain a wide variety of fatty acids, the composition of which is characteristic of the family to which the plant belongs. Generally one fatty acid predominates (Table 4.2). It may either be one of the normal fatty acids, palmitic, oleic, or linoleic, as exemplified by palm oil, olive oil and sunflower seed oil or it may be an unusual acid, for example erucic acid in older varieties of rape seed oil. Coconut oil and palm kernel oil are unusual among seed oils in having a preponderance of saturated fatty acids in which the acids of medium chain length predominate. It is therefore an unjustified generalization to characterize all vegetable oils as unsaturated. 

Prostaglandins arise from unsaturated C20 carboxylic acids such as arachidonic acid (see Table 26 1) Mammals cannot biosynthesize arachidonic acid directly They obtain Imoleic acid (Table 26 1) from vegetable oils m their diet and extend the car bon chain of Imoleic acid from 18 to 20 carbons while introducing two more double bonds Lmoleic acid is said to be an essential fatty acid, forming part of the dietary requirement of mammals Animals fed on diets that are deficient m Imoleic acid grow poorly and suffer a number of other disorders some of which are reversed on feed mg them vegetable oils rich m Imoleic acid and other polyunsaturated fatty acids One function of these substances is to provide the raw materials for prostaglandin biosynthesis... 

Table 9. UOP Sorbex Separation of Saturated and Unsaturated Tall Oil Fatty Acids...

Amides can be titrated direcdy by perchloric acid ia a nonaqueous solvent (60,61) and by potentiometric titration (62), which gives the sum of amide and amine salts. Infrared spectroscopy has been used to characterize fatty acid amides (63). Mass spectroscopy has been able to iadicate the position of the unsaturation ia unsaturated fatty amides (64). Typical specifications of some primary fatty acid amides and properties of bisamides are shown ia Tables 5 and 6. 

Unsaturation in a fatty acid increases its solubihty in organic solvents, and the differences in solubiHties between saturated and unsaturated acids can be used to separate these acids (Table 9). 

Table 4. Unsaturated Fatty Acid Production and Disposition, 10 t...

Properties are furthermore determined by the nature of the organic acid, the type of metal and its concentration, the presence of solvent and additives, and the method of manufacture. Higher melting points are characteristics of soaps made of high molecular-weight, straight-chain, saturated fatty acids. Branched-chain unsaturated fatty acids form soaps with lower melting points. Table 1 Hsts the properties of some soHd metal soaps. 

Table 3 iadicates the autritioaal composition of the three types of egg products, plus the shell egg itself. Eggs, coasidered to be oae of the most autritious foods, have the highest quaHty proteia of any food, and are important as a source of minerals and certain vitamins. Lipids ia eggs are easily digested, and the amount of unsaturated fatty acids is greater than ia most animal products. 

Unsaturated Fatty Acids Contain One or More Double Bonds (Table 14-2)... 

Table 14-2. Unsaturated fatty acids of physiologic and nutritional significance.

In general for the C20 series, maximal activity is achieved with amides of arachidonic acid (1) [81], mead acid (199) [149], and dihomo-y-linoleic acid (200) [150] (see Table 6.18). Decreasing the unsaturation (201), (202), or abolishment of the n-pentyl chain (203) [150] led to less active or inactive compounds. Variable results were seen with longer chains. The C22 4 n-6 analogue (204) is as active as AEA (1) whereas the C22 6 n-3 analogue (205) is less active than the C20 5 n-3 analogue (203) [150]. Replacement of the double bonds with triple bonds (206) resulted in loss of activity [150] (see Table 6.18). Forcing the fatty acid chain into a hairpin conformation by cyclisation (207) also resulted in inactive compounds [151]. 

The major components have been identified tentatively as phenolic and fatty acids. At this time, seven phenolics have been identified in only four of the fractions. These are shown in Table III. A measure of the magnitude of the confidence level (cc) with a spectrum of standards is given. The first three entries are from the sunflower the last, from the Jerusalem artichoke. In all fractions isolated, both from the sunflower and the Jerusalem artichoke, a homologous series of fatty acids ranging from Cjo to Ci8 have been identified also by GC-MS. Even-chain, Cj6 to Cjs saturated and Cxs mono- and di-unsaturated, predominated. This is not surprising, since fatty acids are major constituents of plant... 

Lipoxygenases, which catalyse the oxidation of unsaturated fatty acids containing the cis,cis-l,4-pentadiene moiety to the corresponding 1 -hydroperoxy-f rans,ds-2,4-diene (Table 2.3), are widely distributed in plants and animals. The mammalian... 

An example of the large variety of monomer structures present in poly(HAMCL) is given in Fig. 2. Also different degrees of unsaturation in poly(HAMCL) can be established relatively easily [3-5,34-39]. For example, the compositional data in Table 1 for the repeat units show that about 16% of the mono-unsaturated double bonds are incorporated when oleic acid is used as feedstock. When tall oil fatty acids are used, over 40 % of the subunits of the resulting poly(HAMCL) are mono- or di-unsaturated, while the total degree of unsaturation of the alkyl side chains of linseed oil-based PHA is even higher (>65%). Moreover, a substantial part (about 30%) of these unsaturated linseed oil-based poly(HAMCL) subunits have up to three double bonds present. 

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