Fatty-acids

Fatty acids are long carbon chains with a carboxylic acid end. They serve three basic functions in the human body 1. they serve as hormones and intracellular messengers (he. eicosanoids such as prostaglandins) 2. they are components of the phospholipids and glycolipids of cell membranes 3. they act as fuel for the body. The first of these functions will not be tested on the MCAT unless it is explained in a passage. For the second function of fatty acids you should be able to recognize the stnicture of a phospholipid as shown in Lecture 3 of the biology manual. 

As fuel for the body, fatty acids are stored in the form of triacylglycerols. Triacylglycerols can be hydrolyzed to form glycerol and the corresponding fatty adds in a process called lipolysis. Notice that this process is simply the reverse of esterification. In the lab triacylglycerols can be cleaved by the addition of NaOH, a process called saponification. Saponification is the production of soap. 

For nomenclature purposes, the carbonyl carbon of a fatty acid is assigned the number 1. The carbon next to the carbonyl is called the a-carbon (alpha carbon) and the carbon at the opposite end of the chain is called the W-carbon (omega carbon). The pof most fatty acids is around 4,5, so most fatty acids exist in their anion form in the cellular environment. 

The carbon chains on fatty acids may be saturated or unsaturated. Fatty acids are amphipathic, meaning they contain a hydrophobic and a hydrophilic end. Since the hydrophobic carbon chain predominates, fatty acids are nonpolar. 

Tile important things to remember about fatty acids are molecular structure. Gpolysis. energy storage, and that they enter Into the Krebs cycle two carbons at a time. 

Fatty acids are carboxylic acids with long hydrocarbon chains. If the hydrocarbon chain in a fatty acid is saturated (no carbon-carbon double bonds), then it is called a saturated fatty acid. If there are (one or more) carbon-carbon double bonds in the hydrocarbon chain of a fatty acid, then it is called an unsaturated fatty acid. As the length of the hydrocarbon chain increases, the lipid solubility of fatty acids increases, and the water solubility decreases. Fats and oils are derivatives of fatty acids. 

H3CH2CHC=CHCH2CH=CHCH2CH=CH(CH2)7C00H Linolenic acid 

Triacylglycerols are esters of fatty acids. Fats or triglycerides are triacylglycerols. In a triacylglycerol, a glycerol molecule is linked with three fatty acids by ester linkages. The structure of glycerol is shown below  

Fats can be solid or liquid. This physical property is a direct effect of the fatty acid substituents that are present in them. When fats are in their liquid state they are commonly called oils. Broadly we can generalize that solid fats mainly contain saturated fatty acids, and liquid fats mainly contain unsaturated fatty acids. We should not confuse this generalization with the fact that the naturally occurring fats and oils contain many different types of fatty acids, both saturated and unsaturated. The physical properties of fats are mostly a function of the fatty acids that are present in them. For example, human stored fat contains predominantly oleic acid (a saturated fatty acid) which constitutes about 47 % of the total fatty acid content. It also contains palmitic acid, linoleic acid, stearic acid, myristic acid, and other fatty acids in decreasing amounts respectively. 

Because fatty acids derived from natural sources are present in a mixture, an ideal analysis method for these molecules should be applicable to mixtures without requiring a prior separation or derivatization. Mass spectrometry is an excellent tool for determining the structure of fatty acids present in a mixture. It is possible to determine not only the molecular weight and thus the elemental composition but also, in most cases, the nature and position of the branching and the other substituents on the carbon chain. [268,269] Furthermore, such an analysis requires low quantities ranging from 10 pg to 100 ng of total lipid, depending upon the analysed sample, the ionization method used and the configuration of the spectrometer. [270,271] 

The presence of unsaturation or substituents disrupts or disturbs the characteristics of the spectrum. The nature of the disruption allows one to distinguish the type of structural modification whereas the localization on the chain can be determined from the point where the perturbation occurs. 

4-elimination mechanism of H2 occurring along the fatty acid chain in order to yield fragments corresponding to the loss of an alkene. 

Collision-induced dissociation FAB/MS/MS trace of octadecanoic acid acquired in the negative ion mode at high energy. Reproduced (modified) from Jensen N.J., Tomer K.B. and Gross M.L., Anal. Chem., 57, 2018, 1985, with permission. 

Other modifications of the hydrocarbon chain of fatty acids, such as hydroxylation or introduction of a cyclopropane, cyclopropene or epoxy ring, could be identified and located 

Over 100 fatty acids are known to occur naturally. They vary in chain length and degree of unsaturation. Nearly all have an even number of carbon atoms. Most consist of linear chains of carbon atoms, but a few have branched chains. Fatty acids occur in very low quantities in the free state and are found mostly in an esterified state as components of other lipids. The pKa of the carboxylic acid group is about 5, and under physiological conditions, this group will exist in an ionized state called an acylate ion e.g., the ion of palmitic acid is palmitate, CH3(CH2)i4COO . 

The following are some biologically important fatty acids. 

A number notation used widely for indicating the structure of a fatty acid is shown under the names of the fatty acids in Example 6.3. To the left of the colon is shown the number of C atoms in the acid to the right, the number of double bonds. The position of the double bond is shown by a superscript A followed by the number of carbons between the double bond and the end of the chain, with the carbon of the carboxylic acid group being called 1. 

The number notations, systematic name, and trivial name, respectively, for three more fatty acids are  

The melting points of different fatty acids differ markedly. For example  

Introduction Primary Fatty Acids Fatty Acids of Plant Vegetative Parts Biosynthesis Fatty Acid Biosynthesis The Two-Pathway Model of Lipid Biosynthesis The Second 3-Ketoacyl ACP Synthase Isozyme Biosynthesis of Unsaturated Fatty Acids The Prokaryotic Pathway The Eukaryotic Pathway Biosynthesis of Triacylglycerides Degradation of Fatty Acids Unusual Fatty Acids in Plants Fatty Acids from Unusual Starter Units Fatty Acids with Unusual Patterns of Unsaturation Hydroxy Fatty Acids Epoxy Fatty Acids 

Methyl Branched, Cyclopropanoid, and Cyclopropenoid Fatty Acids 

Cyclopentenoid Fatty Acids Fluoro Fatty Acids Other Unusual Lipids Metabolically Altered Fatty Acids The Green Leaf Volatile Complex Functions of Fatty Acids and Their Derivatives in Plants Jasmonic Acid and Related Compounds The Requirement for Unsaturated Fatty Acids in the Diet of Animals 

Effects of Fatty Acids and Their Derivatives on Animals 

Fatty Acids with Biological Activity Insect Pheromones Derived from Fatty Acids Mammalian Pheromones Analysis of Fatty Acids References 

Waxes are derived from fatty acids. Waxes found in nature include the protective coatings on some fruits and vegetables, the thick smface of cacti and other succulents, the secretions some birds and mammals use to waterproof feathers and fur, and the beeswax in honeycombs. Derived from plants, waxes are used in polishing compounds for cars, furniture, and floors. Waxes are also used in cosmetics. 

Even-carbon-numbered n-fatty acids, in the range C14-C30 are important constituents of the three races of B. braunii where they account for 5 to 14% of dry biomass depending on the strain (20) these are obtained by saponification of hexane and CHCls-MeOH extracts. For a given race, GCMS analyses of their methyl esters indicated rather similar distribution in external and internal lipids. The most abundant fatty acids are palmitic (16 0), oleic (18 1) and octacosenoic (28 1) acids. Oleic acid is markedly predominant in the A race (more than 80% of total fatty acids) this very high level is certainly related to the precursor role of this acid in n-alkadiene and triene biosynthesis. The above n-fatty acids are esterified in the form of various lipid classes including triacyl-glycerols (14). 

The production of volatile fatty acids (VFA) from formic to heptonic acids is a stable characteristic both qualitatively and quantitatively, and allows the differentiation of certain species in the group Bacteroides. The formation of branched chain fatty acids may also be used for differentiation. The use of this property would only be found in a specialised laboratory. 

The presence of these may be used in the differentation of Clostndium spp. They are detected in the medium by means of GLC. Testing for these compounds is not used on a routine basis and would only be found in laboratories specialising in Clostridia. 

CAPITAL CITY PRODUCTS CO. CAPITAL Fatty Acids  

CAPITAL fatty acids are a line of high quality acids derived from vegetable oils. 

Fatty acids and their derivatives have a place in practically all phases of modern living. They add needed qualities to pharmaceuticals, cosmetics and other personal care products. They improve the performance of paints, lubricants, textiles, detergents and rubber products. 

One important advantage in the use of fatty acids, as compared to whole oils, is that type-for-type they are more reactive and permit faster and more complete saponification, esterification or other reactions. 

Color Gardner Max. 4 Sap. Value 260-270 Iodine Value 8-16 Acid Value 258-268 Titer C 22-26 Source Oil Coconut 

The carboxylic acids obtained from the hydrolysis of fat or oil are called fatty acids. They are the building blocks of the triglycerides and the fats and oils are often named as derivatives of these fatty acids. For example, the tristearate of glycerol is named tristearin and the tripalmitate of glycerol is named tripalmitin. 

Normal saturated fatty acids have a long, unbranched hydrocarbon chain having a general formula CH3(CH2)nCOOH, where n is usually even and varies from 2 to 24. 

The unsaturated fatty acids may have one double bond (monosatu-rated) or have more than one cis-methylene interrupted double bond (polyunsaturated) as illustrated in Fig. 4.1. 

Wool (anhydrous 36-42 Cholesteryl estolidic esters, alcohol 

The following three systems of nomenclature are in use for naming fatty acids. 

1 -palmitoyl-2-stearoyl-3-olein) and the formulae of the most common fatty acids, their common names and abbreviations 

Fatty acids are indeed synthesized by head-to-tail condensation of two-carbon units, but the reality is a little more complex. In building up fatty acids, nature uses the Claisen condensation to make the new carbon-to-carbon bonds. In the laboratory we use a strong base (ethoxide ions) and anhydrous conditions to make this difficult reaction work between two molecules of ethyl acetate. Nature can perform the same in an 

Inhaled ozone is known to initiate free-radical autooxidation of unsaturated fatty acids in animal pulmonary lipids (Pryor et al., 1981). These reactions lead to the formation of such typical autooxidation products as conjugated dienes and short-chain alkanes like ethane and pentane. Whether these reactions also occur in water treatment is uncertain. Glaze et al. (1988) showed that 9-hexadecenoic acid (83) reacted readily in aqueous solution to form the expected C, and C, aldehydes and acids. Linoleic acid (84) was converted to a mixture of aldehydes and acids (Carlson and Caple, 1977) notably, 3-nonenal (85) was among the products. Isolation of an unsaturated aldehyde is significant because of the high reported toxicity of these compounds. Carlson and Caple (1977) also implied that the epoxide of stearic acid was formed when an aqueous solution of oleic acid was ozonized the product probably derives from an indirect attack on the double bond by peracids or peroxy radicals (Equation 5.39). Nevertheless, it is conceivable that similar reactions could occur in natural waters. 

At low pH, aqueous ozone appears to act as a typical electrophile with aromatic compounds ozone reacts with the electron-rich compound, phenol, more than 6(X) times faster than it does with benzene (Hoigne, 1982). Fundamental studies of the kinetics of ozone-phenol reactions have revealed the expected correlation between electron density, as measured by the Hammett a substituent parameter, and reaction 

Several other groups have observed oxidative coupling reactions of phenols (see Equation 5.10) in the presence of ozone. Chrostowski et al. (1983) exposed several polyphenolic compounds to ozone at various pHs and observed changes in color for example, catechol (86) was observed to develop first a red and then a brown color. 

From Duguet et al. (1988). Reprinted by permission of Lewis Publishers. 

Until recently, gas-liquid chromatography (GLC) was the most popular method for the identification and quantitation of fatty acids however, with the emergence of new derivatisation techniques and improvements in detector technology HPLC offers a viable alternative. The most frequently used HPLC mode for the analysis of fatty acids is reversed phase either with or without pre-column derivatisa- 

The detectors most frequently used to monitor the elution of underivatised fatty acids have been differential refractive index detectors (Bailie et al., 1982 Svensson et al., 1982), moving wire flame ionisation detectors (Ozcimder and Hammers, 1980) and UV detection at low wavelengths (Van Rollins et al., 1982 Batta et al., 1984). Clearly, detection using these methods does not provide very great sensitivity at present and in instances where this is required pre-col-unm derivatisation of the fatty acids should be utilised. 

In the quantitative analysis of fatty acids by HPLC a plethora of reagents have been used to increase the sensitivity of detection. The most popular derivatives formed include benzyl derivatives (Polizer et al., 1973) 2-naphthacyl derivatives (Cooper and Anders, 1974) o-and p-nitrobenzyl derivatives (Knapp and Krueger, 1975) phenacyl derivatives (Borch, 1975) p-bromophenacyl derivatives (Durst et al, 1975) methoxyphenacyl derivatives (Miller et al., 1978), and 1-naph-thylamide derivatives (Ikeda et al., 1983). The benzyl, nitrobenzyl, phenacyl, p-bromophenacyl, methoxyphenacyl, 1-naphthylamide and 

2-naphthacyl derivatives may be monitored with UV detectors at a wavelength of 254 nm and sensitivities are reported which suggest a lower hmit of detection of approximately 4 ng (Cooper and Anders, 1974 Miller et al., 1978). Fluorescent detection of 2-naphthacyl derivatives of fatty acids may also be utilised with excitation and emission wavelengths of 290 nm and 450 nm, respectively, and this provides enhanced sensitivity of detection (Distler, 1980). 

Lipids are chemical components of the cell that are insoluble in water but soluble in nonpolar solvents. Lipids include fatty acids, fats, oils, phospholipids, glyco-lipids, and steroids. Insolubility in water makes lipids an ideal structural component of cell membranes. Lipids make up the containers that separate the interior of the cell from its external environment. Lipids are also used for long-term energy storage and for insulation. We all store extra calories from food as lipids, some of us more than others. 

I Carboxylic acids were first defined in I Section 18.15. 

One class of lipids are the fatty acids, carboxylic acids with long hydrocarbon tails. The general structure for a fatty acid is  

Myristic acid occurs in butterfat and in coconut oil. Myristic acid is an example of a saturated fatty acid—its carbon chain has no double bonds. Other fatty acids—called monounsaturated or polyunsaturated fatty acids—have one or more double bonds, respectively, in their carbon chains. For example, oleic acid— found in olive oil, peanut oil, and human fat—is an example of a monounsaturated fatty acid. 

The long hydrocarbon tails of fatty acids make them insoluble in water. Table 19.1 lists several different fatty acids and some common sources for each. 

Bovine milk fat is regarded as one of the most complex naturally-occurring fats and oils, because of the large number of fatty acids with a variety of structures. Using a combination of chromatographic and spectroscopic 

The major application described in the James-Martin landmark paper on gas-liquid chromatography is the separation and quantitation of fatty acids (FA). Indeed, it has remained as one of the major applications to this date. It has been estimated [350] that some 25% of all papers published in the field of GC involve, in one way or another, FA or their derivatives. A vast range of samples have been analyzed for FA animal and plant oils, foodstuffs, bacterial products, glandular secretions of animals, and various physiological fluids and tissues, just to mention a few. As more and more information is being sought concerning the composition of various lipids, the applications are expected to increase even further in the future. 

Determination of lower FA (typically, Cj-Cj) are of particular importance in microbiology, characterization of fermentation products and related industrial prob- 

Resolution problems in the GC analysis of FA esters prompted many investigators in the past to develop capillary techniques to search for more selective stationary phases, and ultimately, to combine both approaches whenever required. In fact, FA esters were among the first substances (beyond hydrocarbons) that were successfully chromatographed on stainless steel capillary columns [355]. The most difficult separations involve different geometrical isomers, and the presence and positions of unsaturated carbon-carbon bonds. Such separations are non-trivial and justify the effort of numerous laboratories to solve these problems. 

Clearly, the polyester stationary phases advocated earlier (79) in the field of lipid separations possess only a limited thermal stability. Cyanopropyl silicones [356,357] now provide selective and more stable stationary phases for the separation of FA esters. However, the column selectivity alone falls short of some resolution requirement, while capillary GC seems to be the most profitable route to pursue. The state-of-the-art separation of FA methyl esters is reflected in Fig. 3.21 [358], where many of the minor structural differences in the chromatographed FA molecules yield readily distinguishable peaks. Acquisition of suitable standards as well as extensive correlations of FA molecular parameters with retention characteristics [359] are now clearly needed. 

Characterization of unsaturated FA, as well as those FA that possess some substitution in the chain, is clearly a difficult task. As it was indicated in the previous section on derivatization, a continual suggestion of new derivatives from different laboratories over the years point to some deficiencies in this area [221]. In addition, better methods are needed to recover quantitatively polyunsaturated acids from various lipids [210]. Lipid unsaturation is of much current interest in relation to medicine and dietary research. 

This is usually considered to be essentially monolayer adsorption with competition between solvent and solute. The non-electiolytes that have been studied are mainly fatty acids, aromatic acids, esters and other single functionless group compounds plus a great variety of more complex species such as porphyrins, bile pigments, carotenoids, lipoids and dyestuffs. 

When fatty acid molecules are closely packed on the surface of distilled water, each molecule occupies an area of 0.205 nm irrespective of the length of the hydrocarbon chain. This property was used by Harkins and Cans [22] for the determination of the surface area of titanium dioxide using oleic acid, with results in general agreement with microscopy. Since then the method has been used extensively and a detailed review is to be found in Orr and Dallavalle [52] 

Smith and Fuzek [47] used the gravimetric method described earlier. They also used a procedure in which 20 mL of solvent containing 0.2 to 0.4 g of fatty acid were placed in a tube and mixed for 24h. After this time the tube was centrifuged, 10 mL of the liquid was withdrawn and 10 mL of pure solvent added. The procedure was then repeated. The fatty acid content of the withdrawn samples was determined as before. 

Gregg used the same solvent [53] but determined the amount adsorbed using a surface tension balance. Smith and Hurley [17] recommended the use of cyclohexane as solvent, and stated that with some solvents multilayer adsorption takes place. Hirst and Lancaster [54], instead of adding more fatty acid to the solvent, increased c/cj by lowering the temperature of Uie solution. 

The specific surface area determined by liquid phase adsorption is usually low due to solvent adsorption. It is thus preferable that determinations be carried out with a variety of solvents and comparisons made between them. 

This is the most abundant group of compounds that are classified as lipids. They occur as isolated molecules and are more commonly found as residues in other lipid structures. The fatty acids and residues that are commonly found are normally referred to by trivial names (Table 1.4). They usually have straight chain structures with even numbers of between 14 and 22 carbon atoms inclusive. Both saturated and unsaturated residues are found. In the latter case both cis and trans isomers are known but the cis isomers are more common. A few residues have structures that have side chains and/or other functional groups. 

Lipids are water-insoluble that are either hydrophobic (nonpolar) or amphipathic (polar and nonpolar regions). Lipids are in many ways the most diverse of the biological macromolecules, since they are something of a rag-tag bunch of leftovers. Lipids are pretty much everything in the cell that isn t very water soluble, and chemically they don t have a great deal in common with one another. The best known lipids are probably the fatty acids, so that is where we shall start. 

The fatty acids are long chain carboxylic acids synthesised by the condensation and reduction of acetyl coenzyme-A units by fatty acid synthase. The more important ones have nonsystematic names in wide use. Stearic and palmitic acids are saturated (no double bonds), oleic acid is monounsaturated, and linoleic and linolenic are polyunsaturated (Table 3.1). All these common fatty acids are cis (E) fatty acids. Because of the links in the chain caused by the double bonds, the unsaturated fatty acids tend to be liquids at room temperature (they are less easy to pack together to form a solid). Bacteria and plants (which cannot thermoregulate) will use more unsaturated acids in their cell membranes when they are exposed to cold this helps to maintain membrane fluidity. 

The nomenclature of these acids is rather complicated. There are at least five systems in use. Here are some of the above in the different systems. The delta system numbers the double bonds from the carboxyl group (the A carbon), whereas the omega system indicates where the first double bond is counting from the other end of the molecule (the (o carbon). 

Fatty Acid Systematic Colon Delta Omega 

Stearic acid Octadecanoic acid 18 0 Octadecanoic acid - 

The lipid class of compounds also includes some important food aroma substances or precursors which are degraded to aroma compounds. Some lipid compounds are indespensable as food emulsifiers, while others are important as fat- or oil-soluble pigments or food colorants. 

Fatty acids are usually denoted in the literature by a shorthand description , e. g. 18 2 (9, 12) for linoleic acid. Such an abbreviation shows the number of carbon atoms in the acid chain and the number, positions and configurations of the double bonds. All bonds are considered to be cis whenever trans-bonds are present, an additional tr is shown. As will be outlined later in a detailed survey of lipid structure, the carbon skeleton of lipids should be shown as a zigzag line (Table 3.2). 

FIGURE 5.7 Enzyme cascade for the complete oxidation of glycerol to carbon dioxide. (Reproduced with permission from Ref. [99]. Copyright 2009, Wiley-VCH Verlag GmbH.) 

Monooxygenase is another enzyme that requires an NADP(H) cofactor to oxidize unsaturated fatty acid bonds to a hydroxyl group. Immobilization of the flavin-containing monooxygenase-3 has not been studied for BFC applications, but it has been used in a trimethylamine biosensor [103]. 

FIGURE 15.1 Lipids are naturally occurring compounds in cells and tissues, which are soluble in organic solvents but not in water. 

3 Lipids are not soluble in water. Are lipids polar or nonpolar molecules  

4 Which of the following solvents might be used to dissolve an oil stain  

A fatty acid contains a long, unbranched carbon chain with a carboxylic acid group at one end. Although the carboxylic acid part is hydrophilic, the long hydrophobic carbon chain makes fatty acids insoluble in water. 

Most naturally occurring fatty acids have an even number of carbon atoms, usually between 12 and 20. An example of a fatty acid is lauric acid, a 12-carbon acid found in coconut oil. In a skeletal formula of a fatty acid, the ends and bends of the line are the carbon atoms. The structural formula of lauric acid can be drawn in several forms. 

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CH3-[CH2],8-C00H. M.p. 75 C. A fatty acid occurring as glycerides in peanut and other vegetable oils. 

CH3 [CHJb-COOH. M.p. 31 5"C, b.p. 268-270 C. A fatty acid, occurring in wool as the potassium salt, as esters in fusel oil, and as glycerides in cows and goats milk and coconut and palm oils. 

HisN03,(CH3)3N + -CH2 CH0H CH2C00-. Isolated from skeletal muscle. It acts as a carrier for ethanoyl groups and fatty acyl groups across the mitochondrial membrane during the biosynthesis or oxidation of fatty acids. 

C22H34O2. A straight-chain fatty acid with 5 double bonds. A major component of fish oils and the oils of marine animals, clupeine Protamine class protein found in the sperm and testicles of the herring. On hydrolysis it gives about 90% of argenine. 

EDTA Efhylenediamineletra-acetic acid. EFA Essential fatty acids. ... 

Fats are hydrolysed to glycerol and fatty acids by boiling with acids and alkalis, by superheated steam and by the action of lipases. If alkalis are used for hydrolysis, the fatty acids combine with the alkalis to form soaps. Alkaline hydrolysis is therefore sometimes called saponification. 

There also exist natural fatty acids with four or more double bonds, fatty acids with hydroxy groups in the molecule, and certain cyclic fatty acids. 

The lower members of the series are liquids soluble in water and volatile in steam. As the number of carbon atoms in the molecule increases, the m.p. and b.p. rise and the acids become less soluble in water and less volatile. The higher fatty acids are solids, insoluble in water and soluble in organic solvents. 

The fatty acids occur in nature chiefly as glycerides see fats), which constitute the most important part of the fats and oils, and as esters of other alcohols, the waxes. The naturally occurring fatty acids are mostly the normal straight-chain acids with an even number of carbon atoms. 

Lecithins are fatty acid esters of glycero-phosphoric acid derivatives. Commercially glycerophosphoric acid is used to prepare the medicinal glycerophosphate salts, c.g. the calcium salt. 

C12H24O, CH3 [CH,]io COOH. Needles, m.p. 44 C, b.p. 225"C/I00mm. A fatty acid occurring as glycerides in milk, spermaceti, laurel oil, coconut oil, palm oil and other vegetable oils. The metal salts are widely used. 

CifiHjjOi. A fatly acid which is easily oxidized in air.-It occurs widely, in the form of glycerides, in vegetable oils and in mammalian lipids. Cholesieryl linoleale is an important constituent of blood. The add also occurs in lecithins. Together with arachidonic acid it is the most important essential fatty acid of human diet. 

The base lubricant is usually a petroleum oil while the thickener usually consists of a soap or soap mixture. In addition they may contain small amounts of free alkali, free fatty acid, glycerine, anti-oxidant, extreme-pressure agent, graphite or molybdenum disulphide. 

C27H55COOH. Glistening scales m.p. 89 C. A straight-chain, saturated fatty acid, that occurs in many natural waxes. 

Colourless liquid. B.p. 286 C/100 mm., insoluble in water. Oleic acid occurs naturally in larger quantities than any other fatty acid, being present as glycerides in most fats and oils. It forms one third of the total fatty acids of cow s milk. A crude grade from inedible tallow is used in the production of lubricants, detergents, resins and other products. 

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