Fatty acid characteristics

Thiele R, Mueller-Seitz E, Petz M (2008) Chili pepper fruits presumed precursors of fatty acids characteristic for capsaicinoids. J Agric Food Chem 56 4219 224 Fujiwake H, Suzuki T, Oka S, Iwai K (1980) Enzymatic formation of capsaicinoid from vanU-lylamine and iso-type fatty acids by ceU-free extracts of Capsicum annuum var. annuum cv. Karayatsubusa. Agric Biol Chem 44 2907-2912... 

Guiet et al. (2003) demonstrated that deuterium (2H) distribution in fatty acids was non-statistical and could be related to isotopic discrimination during chain extension and desaturation. Petroselinic acid (C18 1A6) (Fig. 21.4), a fatty acid characteristic of the seeds of the Apiaceae, has been shown to be biosynthesized from palmitoyl-ACP (C16 0) by two steps, catalysed by a dedicated A4-desaturase and an elongase. The isotopic profile resulting from this pathway is similar to the classical plant fatty acid pathway, but the isotopic fingerprint from both the desaturase and elongase steps shows important differences relative to oleic and linoleic acid biosynthesis. 

Unlike the SMB, where a 6 C fatty acid anomaly was noted, the fatty acid fraction in the Antarctic sediments exhibits a value comparable to other fractions, but lower than the bulk extracted sediment and within the range of Cje and Cjg fatty acids characteristic of marine origin (UcHiDA et al., 2001). This conclusion is also consistent with the carbon number distribution of alkanes, alkenes, fatty acids, alcohols and sterols which reflects the predominance of marine-derived carbon with little recognizable higher plant debris in the sediment. Similar molecular distribution of the lipid classes has previously been reported in sediments from the same general locations in the McMurdo Sound (Venkatesan, 1988). 

The main component of detergents is surfactant. The eldest known surfaetant is soap. Chemically soap is an alkaline salt of fatty acid. Characteristic of soap (and surfactant) is the molecular structure consisting of apolar - hydrophobic - part (fatty acid) and a polar - hydrophilic - part (-COONa), causing surface activity in aqueous solution. 

Some Unusual Fatty Acids Characteristic of the Seed Oils of Certain Plant Families... 

Compared to phospholipids, the incorporation of radioactive fatty acids into galactolipids in vivo is usually quite slow. This is certainly the case in D. salina (Fig. 1). Our studies (1) suggest that the relatively rapid uptake of fatty acids into phospholipids is due not only to de novo synthesis but also to an active metabolic turnover of the acyl chains bound to existing phospholipids. In contrast, there is little evidence that the acyl chains of galactolipids are replaced in this way. For example, we have not detected the polyunsaturated Ci5-fatty acids characteristic of D. salina galactolipids in the cell s free fatty acid pool, although all the fatty acids that typically occur bound to phospholipids are represented in that pool (Pike CS and Thompson GA Jr, unpublished observations). 

Table I. Fatty acids characteristic of major groups of organisms...

Pranal, V, Fiala-Medioni, A and Guezennec, J. (1996) Fatty acid characteristics in two symbiotic gastropods from a deep hydrothermal vent of the West Pacific. Mar. Ecol. Prog. Ser., 142,175-184. 

In the area of moleculady designed hot-melt adhesives, the most widely used resins are the polyamides (qv), formed upon reaction of a diamine and a dimer acid. Dimer acids (qv) are obtained from the Diels-Alder reaction of unsaturated fatty acids. Linoleic acid is an example. Judicious selection of diamine and diacid leads to a wide range of adhesive properties. Typical shear characteristics are in the range of thousands of kilopascals and are dependent upon temperature. Although hot-melt adhesives normally become quite brittle below the glass-transition temperature, these materials can often attain physical properties that approach those of a stmctural adhesive. These properties severely degrade as the material becomes Hquid above the melt temperature. 

Fats and fatty oils). For the most part, oil is contained in the kernel or embryo of the seed, though it can also occur in the flesh of the ginkgo fmit and in the endosperm of coconut, palm, and pine nuts. Relative amounts of some fatty acids present in a few types of nuts are given in Table 5. Considerable variations in the percentages of fatty acids have also been reported in both pecan and peanut oils from a variety of sources. (Table 6). (For main physical characteristics and the composition of nut oils, see Fats and fatty oils. 

The physical properties of the fatty acid ethoxylates depend on the nature of the fatty acid and even more on ethylene oxide content. As the latter increases, consistencies of the products change from free-flowing Hquids to slurries to firm waxes (qv). At the same time, odor, which is characteristic of the fatty acid, decreases in intensity. Odor and color stabiUty are important commercial properties, particularly in textile appHcations. Oleic acid esters, though possessing good functional properties, cannot be used because they tend to yellow on exposure to heat and air. 

The solubihty characteristics of sodium acyl isethionates allow them to be used in synthetic detergent (syndet) bars. Complex blends of an isethionate and various soaps, free fatty acids, and small amounts of other surfactants reportedly are essentially nonirritant skin cleansers (66). As a rule, the more detersive surfactants, for example alkyl sulfates, a-olefin sulfonates, and alkylaryl sulfonates, are used in limited amounts in skin cleansers. Most skin cleansers are compounded to leave an emollient residue on the skin after rinsing with water. Free fatty acids, alkyl betaines, and some compatible cationic or quaternary compounds have been found to be especially useful. A mildly acidic environment on the skin helps control the growth of resident microbial species. Detergent-based skin cleansers can be formulated with abrasives to remove scaly or hard-to-remove materials from the skin. 

Many of the surfactants made from ethyleneamines contain the imidazoline stmcture or are prepared through an imidazoline intermediate. Various 2-alkyl-imidazolines and their salts prepared mainly from EDA or monoethoxylated EDA are reported to have good foaming properties (292—295). Ethyleneamine-based imida zolines are also important intermediates for surfactants used in shampoos by virtue of their mildness and good foaming characteristics. 2- Alkyl imidazolines made from DETA or monoethoxylated EDA and fatty acids or their methyl esters are the principal commercial intermediates (296—298). They are converted into shampoo surfactants commonly by reaction with one or two moles of sodium chloroacetate to yield amphoteric surfactants (299—301). The ease with which the imidazoline intermediates are hydrolyzed leads to arnidoamine-type stmctures when these derivatives are prepared under aqueous alkaline conditions. However, reaction of the imidazoline under anhydrous conditions with acryflc acid [79-10-7] to make salt-free, amphoteric products, leaves the imidazoline stmcture essentially intact. Certain polyamine derivatives also function as water-in-oil or od-in-water emulsifiers. These include the products of a reaction between DETA, TETA, or TEPA and fatty acids (302) or oxidized hydrocarbon wax (303). The amidoamine made from lauric acid [143-07-7] and DETA mono- and bis(2-ethylhexyl) phosphate is a very effective water-in-od emulsifier (304). 

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. 

Consumer acceptance of milk is strongly determined by its sensory characteristics. The development of off-flavor in milk as a result of lipolysis can reduce the quality of milk. The enzymatic release, by milk lipase, of free fatty acids (FFA) from triglycerides causes a flavor defect in milk described as rancid . Triglycerides in milk contain both long chain and short chain fatty acids, which are released at random by milk lipase. The short chains FFA, like butyric acid, are responsible for the off-flavor. 

---