What Are Fatty Acid Chains

Fatty Acids

Catalysis, Dark-green Chemistry and Sustainable Energy

Antonio Zarli , in Studies in Surface Scientific discipline and Catalysis, 2020

3.i.2 Fatty acids distillation process

The fatty acids produced past fatty-splitting process are distilled and eventually fractionated past fractional distillation in fatty acid cuts or even individual fat acids. The principal requirement to produce distilled fatty acids is to remove low and high boiling components every bit well as odor bodies, residue, and other impurities. Fatty acids are sensitive to heat, can be oxidized, and generate corrosion phenomenon; this is due to the reactive acid grouping at the end of the long carbon chain [ 6]. The thermolability of fat acids requires a proper and competent approach for the design of a distillation unit of measurement. Distillation is carried out under loftier vacuum and lower temperatures and with the shortest residence time at the column bottom end to avoid nifty or polymerization reaction and the consequent bad impact on yield and product quality.

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13C NMR Studies of the Interactions of Fatty Acids with Phospholipid Bilayers, Plasma Lipoproteins, and Proteins

James A. Hamilton , in Carbon-xiii NMR Spectroscopy of Biological Systems, 1995

iv.2 Backdrop of Fatty Acids

Unesterified fatty acids (FAs) are a key intermediate in lipid metabolism. They also found an important metabolic fuel in sure cells ( Neely and Morgan, 1974). In addition to these long-recognized roles, FAs have diverse biological activities. For instance, they serve as second messengers in point transduction (Hannigan and Williams, 1991) and actuate 1000⁺ (Ordway et al., 1989) and Ca⁺⁺ channels (Huang et al., 1992). Structurally, FAs consist simply of a hydrocarbon chain terminating in a carboxyl grouping. In human physiology, FAs are predominantly long-concatenation species (> 12 carbons) of variable length and saturation. Typical dietary fats include palmitic (sixteen:0), oleic (eighteen:1), stearic (18:0), and linoleic (xviii:2) acid. Certain less abundant FAs are of import in diseases. For example, the very-long-chain FA hexacosanoic acrid (26:0) accumulates in the tissues of patients with the rare just sometimes fatal inherited diseases adrenoleukodystrophy and Zellweger syndrome (Moser, 1992). Medium-chain FAs (octanoic, 8:0 and decanoic, ten:0) are not prevalent in normal diets but are fed intravenously to patients with impaired lipid uptake and metabolism (Kuo and Huang, 1965).

Long-chain FAs are very insoluble in an aqueous medium (John and McBain, 1948; Vorum et al., 1992) and form acid-soap lamellar aggregates at pH 7.4 rather than micelles (Gebecki and Hicks, 1973; Cistola et al., 1986). In vivo, FAs bind to extracellular and intracellular binding proteins and to membranes. In general, the affinities of membranes and such proteins are sufficiently loftier to keep the aqueous concentration of FAs below the solubility limit, preventing precipitation. In human plasma nigh of the FAs are jump to albumin, a 65-kD protein that transports FAs to, and removes FAs from, tissues. A pocket-sized, but sometimes significant, portion of FAs is bound to plasma lipoproteins. A family unit of intracellular proteins, fatty acid binding proteins (FABPs), demark FAs with loftier affinity in vitro, but their precise physiological function remains to exist determined (Veerkamp et al., 1991). Jail cell membranes demark FAs avidly and serve as the sites for some metabolic events and probably for many of the biological activities of FAs.

The interactions of FAs with binding proteins and membranes are therefore of general involvement. The illumination of molecular details of such interactions past classical methods other than NMR has proved hard, in part because of the simple structure of FAs. The lack of chromophoric or reporter groups, which could serve as intrinsic probes of their interactions, has led some experimentalists to add together nitroxide or fluorescent groups to FAs, but such covalent modifications alter the properties of FAs. The FA studies described in the post-obit sections are based on the use of specific ¹³C enrichment, which causes minimal perturbation of the FA molecule and averts the need to use non-native FAs.

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Pharmaceutical nanotechnology: Brief perspective on lipid drug delivery and its current scenario

Karthik Siram , ... R. Hariprasad , in Biomedical Applications of Nanoparticles, 2019

2.1 Fatty acids

Fat acids are the fundamental building blocks of lipids and form the major component of the body fat. They consist of hydrophilic carboxylic group (head portion) to which lipophilic long chain of alkyl groups (tail portion) is attached. The tail commonly contains even number of carbon atoms. Each fatty acrid differs in their chain length, degree of saturation, and position of double bond. They are usually classified based on the presence or absenteeism of double bonds or either based on the number of carbon atoms present in the alkyl concatenation length ( Jannin et al., 2008; Zheng et al., 2012; Cerpnjak et al., 2013; Chen, 2008). Table 1 lists out few fatty acids that are commonly used.

Table 1. Details of the Chain Length and Number and Position of Double Bonds in Fat Acids Used as Lipid-Based Excipients

Fatty Acid Chain Length (Number of Carbon Atoms)	Number and Position (Δ) of Unsaturated Bonds	Common Proper noun	Melting Temperature (°C)
eight	0	Caprylic acid	16.5
ten	0	Capric acid	31.6
12	0	Lauric acid	44.viii
14	0	Myristic acid	54.iv
16	0	Palmitic acrid	62.nine
18	0	Stearic acid	70.1
18	1 Δ nine	Oleic acid	16.0
18	ii Δ nine,12	Linoleic acid	− five.0
18	3 Δ 6,9,12	γ-Linolenic acid	− eleven.0
18	1 Δ 9 (− OH:12)	Ricinoleic acrid	6.0
20	0	Arachidic acid	76.1
22	0	Behenic acrid	80.0

Based on the number of carbon atoms in the alkyl chain length, fatty acids tin can be classified into short-chain (2–four carbon atoms), medium-chain (6–x carbon atoms), and long-chain fatty acids (12–26 carbon atoms) (Shete and Patravale, 2013; Trevaskis et al., 2008).

They tin be classified into saturated or unsaturated fatty acids based on the absenteeism or presence of double bonds, respectively. Usually, unsaturated fat acids have lower melting points and exist as liquid at room temperature. Behenic acid, stearic acid, and palmitic acid are few of the examples of saturated fat acids. Oleic acid, linoleic acid, and linolenic acrid are few of the examples of unsaturated fatty acids. As saturated fatty acids are comparatively tightly packed together than unsaturated fatty acids, saturated fatty acids have higher melting points. Hence, unsaturated fatty acids exist in liquid state at room temperature (Jannin et al., 2008; Caliph et al., 2000). The melting points of the fat acids are also more often than not influenced by the length and degree of unsaturation of the hydrocarbon concatenation. The saturated fatty acids from 12:0 to 24:0 have a waxy consistency at room temperature. But, unsaturated fat acids (of similar carbon chains) be every bit oily liquids due to different degrees of packing among the fatty acid molecules. Free rotation around the carbon-carbon bond in the saturated fatty acids gives the hydrocarbon chain great flexibility; thereby, the steric hindrance is depression. These atoms/molecules are packed together by van der Waals forces in nigh crystalline arrays, whereas in unsaturated fat acids, the presence of cis double bonds causes curve in the hydrocarbon chain that does non favor tight packing amid the atoms/molecules. Thus, their interactions amid the molecules are weak with lower melting points than saturated fatty acids of similar chain lengths (Shete and Patravale, 2013; Yáñez et al., 2011; Chen, 2008). As animate being fats contain more than number of saturated fatty acids than vegetable oils, their melting points are higher than the vegetable oils.

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Recent Progress in Mesostructured Materials

M. Musteata , ... S. Kaliaguine , in Studies in Surface Science and Catalysis, 2007

i Introduction

Acylation of fatty acids with amino-alcohols leads to valuable surfactants. In spite of this practical importance the literature is deficient, and the very few contributions in this subject refer to synthesis of pharmaceutical applications [1]. I of the major problems encountering in these syntheses is the regioselectivity, O- or N- acylation leading patently to compounds with different properties [ii]. To control O-acylation, Kihara et al. [iii] suggested the use of trifluoromethanesulfonic acid as catalyst in the presence of a crown ether. Another serious problem concerns the conditions in which these reactions are carried out. All the reported acylations occur under very non-dark-green conditions, using fatty acrid chlorides and homogeneous acrid Lewis catalysts.

The aim of this study was to investigate a green route for the acylation of oleic acid with ethanolamine, with a good command of selectivity. Since these molecules are very big, heterogeneous catalysis requires mesoporous materials.

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Reaction Kinetics and the Development of Catalytic Processes

T. García , ... J. Aracil , in Studies in Surface Scientific discipline and Catalysis, 1999

half dozen. Nomenclature

Ac: Fatty acid (ricinoleic acid)

C_A: Concentration of component A (mol/i)

Di: Diglyceride of ricinoleic acrid

E: Free enzyme

Gly: Glycerol

G_eq: Equilibrium constant

Thou_iA: Inhibition abiding for component A (mol/1)

K_mA: Michaelis-Menten constant for component A (mol/i)

Due north_A: Number of moles of component A (mol)

Mono: Monoglyceride of ricinoleic acid

P: Pressure (mm Hg)

(-r_A): Reaction rate for component A consumption (mol. l⁻¹.g_cat ⁻¹.min⁻¹)

t: Reaction fourth dimension (min)

T: Temperature (°C)

Due west: Water

w: Corporeality of goad (%)

Ten_A: Conversion of A component

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Other Possible Examinations Conducted on Burn down Droppings

Eric Stauffer , ... Reta Newman , in Fire Debris Analysis, 2008

xiv.2.4 Forensic Arroyo

When a fire investigator suspects the presence of vegetable oils as the crusade of a burn, the forensic scientist tin can aid in the investigation. The questions requiring answers pertain to (i) whether in that location were any vegetable oils present in the debris, (2) whether those vegetable oils were prone to spontaneous ignition, and (3) whether those vegetable oils underwent spontaneous ignition. Figure 14-vi summarizes these questions with the proper forensic approach to answer them.

The detection of fatty acids in nature and in proportions similar those found in known vegetable oil reference materials is sufficient to confirm the presence of a vegetable oil. The determination of the type and amount of the fatty acids nowadays provides an guess of the propensity toward spontaneous ignition. However, this estimate must be made with keen caution because there are two phenomena that are not taken into business relationship in this analysis:

▪: Antioxidants, which slow downwardly the autooxidation process, or driers, which increase the rate of the autoooxidation process, frequently are added to oils. This information, unfortunately, is non available when analyzing the fatty acid content of an oil.
▪: Degradation of the components of an oil is not compatible, thus skewing the fatty acrid ratios from what they were in the original oil. Equally a result, an oil with a great corporeality of C18:3 and less C18:0 can have this proportion reversed after undergoing self-heating, thus misleading the criminalist on its original self-heating propensity.

The determination of whether or not a vegetable oil underwent spontaneous ignition cannot be made solely by chemical assay at this time—this is the reason why it is shaded in Figure 14-6. The mere presence of a vegetable oil susceptible to spontaneously ignite is not a sufficient condition to establish that the phenomenon of spontaneous ignition occurred. This is similar to finding ignitable liquids at a burn down scene: it does non hateful they were used as accelerants. In that location are other conditions that must be fulfilled in social club to obtain spontaneous ignition, such as proper amounts of oil and substrates, size, shape, and nature of fuel bundle and its surround, also every bit initial temperature [21, 22]. A thermodynamic approach is necessary to resolve this problem [23]. Notwithstanding, some contempo enquiry provided preliminary results with regard to the possibility of producing compounds or patterns of compounds that are specific to the miracle of spontaneous ignition [24]. If such research is farther developed and validated in the future, it might be possible that burn down debris analysis will focus on the detection of these compounds, which would be indicative of the occurrence of the miracle.

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Fetal Endocrinology and Metabolism

C. Lowy , C.R. Thomas , in Current Topics in Experimental Endocrinology, 1983

Publisher Summary

Dissimilar the essential amino and fatty acids, carbohydrates are not obligatory nutrients. In well-nigh species, even so, they are quantitatively important components of the individuals' diet and their inclusion leads to more balanced metabolism. Maternal adaptation to pregnancy is characterized by a hormonal milieu favoring anabolism leading to fat degradation. The advantages of this adaptation are probably to spare glucose for transfer to the fetus and to provide nutrients in the final stages of pregnancy and during lactation, when foraging for food may present difficulties. Placental office is extraordinarily circuitous; the transfer of carbohydrates is by facilitated diffusion and occurs in both directions so that movement of substrate is much more rapid than net accretion by the fetus. The placenta seems impermeable to polypeptide hormones and both maternal and fetal hormones are confined to their respective tissues. Saccharide metabolism is critical in early embryonic evolution in which the deviation of maternal plasma glucose concentration leads to retarded growth and an increased incidence of malformations. Strict homeostasis is essential for normal fetal development. Although the synthesis and secretion of the fetal polypeptide hormones occur very early in gestation, their role is imperfectly understood. Of all the hormones, the effects of insulin are nigh clearly divers.

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Time-Resolved Electron Diffraction

Anatoli A. Ischenko , Sergei A. Aseyev , in Advances in Imaging and Electron Physics, 2014

iii.2.3 Fatty Acrid Crystal Bilayers: Molecular Ensembles

Studies of the bilayer of fatty acids deposited onto a hydrophobic surface using the Langmuir-Blodgett technique were performed using UEC. The Langmuir-Blodgett technique makes it possible to control the molecular deposition of an ordered molecular film layer by layer, and it is frequently used for edifice dissimilar membranes.

Arachidic acid was used every bit an example. The unit of measurement cell for arachidic acrid is characterized by the following set:

$a_{0} = 4.vii - four.9 Å, b_{0} = 8.0 - eight.nine Å, c_{0} = 2.54 - two.59 Å,$

which depends on the pH and the deposition procedure. The increase in the length of the -CH₂-CH₂-CH₂- fragment (by approximately 0.01 Å) was observed experimentally. Effigy iii.10 shows the fourth dimension-dependent intensity of the diffraction indicate.

Chen, Seidel, and Zewail (2005) investigated by UEC a single bilayer (2 chains of C₁₉H₃₉COOH) of arachidonic (eicosanoic) acid. They determined the construction and the orientation of aliphatic chains, too as the size of the molecular subcell (–CH₂–CH₂–). The studies made information technology possible to detect the structural dynamics in the bilayer placed on the substrate, the motion of atoms and self-organization of layers (Ruan, Yang, & Zewail, 2004). Effigy three.ten shows the construction of the investigated bilayer and the corresponding subcell in two directions.

All diffraction patterns consist of spots (and/or bands), that demonstrates a loftier quality of second crystal structure of the arachidonic acrid bilayer and surface of Si (111) substrate functionalized with hydrogen. The diffraction patterns at "negative fourth dimension delays" and a pocket-size electron incidence angle (at parallel and perpendicular incidence directions) suggest that the tilting bending of chains is shut to cypher and the parameters of the bilayer subcell should be given by the post-obit ready:

$a_{0} = 4.seven Å, b_{0} = 8.0 Å, c_{0} = ii.54 Å$

The symmetry of the bilayer corresponds to rhombohedral packing R (001) with the (001)–plane being parallel to the Si(111) –surface. These experimental values of the lattice parameters differ from theoretical values of a ₀ = 4.96 Å, b ₀ = seven.iv Å (Kitaygorodsky, 1971). Such a discrepancy can be explained by the fact that the theoretical values were calculated for infinitely long aliphatic chains and the calculations did not accept into account the terminal carboxyl group of fat acids. Furthermore, the bilayer is consists of two monolayers, and then that the substrate and the conditions of its degradation (e.m., its pressure and pH) definitely play an important function. Annotation that the distance c₀ between the (CH₂)–planes is in agreement with the theoretical value of two.54 Å. In the experiment, the selective structural dynamics of the bilayer was investigated. Every bit shown in Figure 3.x, already at the delay of about 1 ps after the heating pulse, weakening of the Bragg diffraction peaks was observed. The changes in the Bragg diffraction peaks go more prominent for larger temporal delays (ten–100 ps). Intriguingly, both electronic and thermal pulses did not destroy the bilayer, as has been demonstrated in multiple experiments.

The observed behavior of the diffraction pattern reflects the initial stretching (Δc ₀ = 0.one Å) of the subcell in the bilayer induced by the heating pulse, followed by the brake caused by estrus dissipation. The stretching took place with the time abiding of approximately 25 ps, while the subsequent contraction occurs with the fourth dimension abiding of approximately 55 ps. Note that the possible compression on nanosecond temporal intervals is restructure. With a 150-fs temporal resolution in the plane, perpendicular to the molecular bondage, no significant changes were observed (Ruan, Yang, & Zewail, 2004). Here, it should be noted that the morphology and the lattice parameters of the surface layer depend on of the matrix and the modification of the surface (Zanchet et al., 2000).

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Reaction Kinetics and the Evolution and Operation of Catalytic Processes

5.U. Miguel , ... A.F. Errazu , in Studies in Surface Science and Catalysis, 2001

4.4 Influence of initial molar ratio of alcohol/fatty acid

The initial molar ratio of alcohol/fatty acid (N) has an important effect on the equilibrium conversion, which increases with booze excess (effigy 5). As expected, the increment in the amount of one of the reactants shifts the chemical equilibrium towards the product side. On other hand, alcohol excess has an unfavourable outcome on the reaction rate. The reversible kinetic model offered a skilful fit all experiences at different N, although for N = ane (stoichiometric value) higher differences between calculated and experimental values were found.

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Novel Methods to Written report Interfacial Layers

G.Y. Jung , ... M.C. Petty , in Studies in Interface Science, 2001

four Conclusions

Nosotros accept studied the effects of incorporating fat acrid Langmuir-Blodgett films into dual layer organic light emitting structures based on 8-hydroxyquinoline aluminium (Alq) and North,N'-diphenyl-Due north,N'-(3-methylphenyl)-1,1′-biphenyl-4,4′-diamine (TPD). The insertion of arachidic acid layers betwixt the Alq emissive layer and an aluminium cathode was found to produce a threefold increase in the quantum efficiency. The precise mechanism for this enhancement is currently subject to further written report.

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