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The oil of Carapa guianensis showed leishmanicidal activity, with its activity being related to limonoids, but fatty acids are the major constituents of this oil. The present study evaluated the physicochemical, pharmacokinetic, and toxicity profiles of limonoids and fatty acids already identified in the species. Based on these results, 2 limonoids (methyl angosinlate, 6-OH-methyl angosinlate) and 2 fatty acids (arachidic acid; myristic acid) were selected for the prediction of possible targets and molecular docking. Included in this study were: Gedunin, 6a-acetoxygedunin, Methyl angosenlato, 7-deacetoxy-7-oxogedunin, Andirobin, 6-hydroxy-angolensate methyl, 17ß-hydroxyazadiradione, 1,2-dihydro-3ß-hydroxy-7-deacetoxy-7oxogedunin, xyllocensin k, 11beta-Hydroxygedunin, 6a,11-11ß-diacetoxygedunin, Oleic Acid, Palmitic Acid, Stearic Acid, Arachidic Acid, Myristic Acid, Palmitoleic Acid, Linoleic Acid, Linolenic Acid, and Beenic Acid. Regarding physicochemical aspects, fatty acids violated LogP, and only limonoid 11 violated Lipinski's rule. A common pharmacokinetic aspect was that all molecules were well absorbed in the intestine and inhibited CYP. All compounds showed toxicity in some model, with fatty acids being mutagenic and carcinogenic, and limonoids not being mutagenic and carcinogenic at least for rats. In in vivo models, fatty acids were less toxic. Molecular dockings were performed on COX-2 steroids (15 and 16) and hypoxia-inducible factor 1 alpha for limonoids (3,6), with this target being essential for the intracellular development of leishmania. Limonoids 3 and 6 appear to be promising as leishmanicidal agents, and fatty acids are promising as wound healers. [ABSTRACT FROM AUTHOR]

Despite ample knowledge of the effect of warm-dry storage on breaking dormancy in chincuya (Annona purpurea Moc. & Sessé ex Dunal) seeds, this paper investigates an important new aspect of this process—the applicability of seed treatment with gibberellic acid and its influence on seed viability and fatty acid profile. Chincuya is an underutilized, tropical wild species native to Mexico, with potential as a biopesticide. The impact of warm-dry storage and gibberellic acid treatment on seed viability and germination was determined to improve that knowledge further. Also, the content and kinetics of fatty acids in chincuya seeds were profiled during warm-dry storage. Seed treatments included storage time (0, 3, 6, 9, and 12 months), seed imbibition for 72 h in gibberellic acid at 350 mg L−1, and distilled water imbibition for 72 h for the control treatment. Seed viability was determined using the TTZ classic test. Imbibed seeds were germinated on paper towels and incubated at 30 °C during the day and 25 °C at night in a 12:12 h dark/light photoperiod. The lipid profile was obtained by gas chromatography. During the storage treatment, seeds stayed in darkness at 25 ± 3 °C. Results showed that high viability remained up to month 9 in storage when it significantly decreased. Freshly harvested seeds germinated at a statistically significantly lower rate (26.1%) than six-month-old seeds (65.6%). The profile of fatty acids breaks down as palmitic acid (33.41%), stearic acid (7.72%), and arachidic acid (1.30%), for a total of 42.44% of saturated fatty acids. The detected unsaturated fatty acids (52.15%) were palmitoleic acid (1.52%), oleic acid (43.37%), and linoleic acid (7.24%). No significant changes were detected in fatty acid content; however, the highest fatty acid content (92.84%) occurred with the highest germination rate. Regression analysis showed significant content changes: palmitoleic and palmitic acids increased while oleic acid decreased during dry storage. Arachidic acid showed a slight downward trend. Also, fatty acid content significantly differed between intact seeds (unstored and unincubated) and latent seeds (unstored, incubated, and ungerminated). The total fatty acids content for latent seeds was significantly lower. These results show that Annona purpurea seeds present morphophysiological dormancy. Also, we document the highest germination rate reported (65.6%) and report the presence of arachidic and palmitoleic acids in chincuya seeds. [ABSTRACT FROM AUTHOR]

The oil of Carapa guianensis showed leishmanicidal activity, with its activity being related to limonoids, but fatty acids are the major constituents of this oil. The present study evaluated the physicochemical, pharmacokinetic, and toxicity profiles of limonoids and fatty acids already identified in the species. Based on these results, 2 limonoids (methyl angosinlate, 6-OH-methyl angosinlate) and 2 fatty acids (arachidic acid; myristic acid) were selected for the prediction of possible targets and molecular docking. Included in this study were: Gedunin, 6α-acetoxygedunin, Methyl angosenlato, 7-deacetoxy-7-oxogedunin, Andirobin, 6-hydroxy-angolensate methyl, 17β-hydroxyazadiradione, 1,2-dihydro-3β-hydroxy-7-deacetoxy-7-oxogedunin, xyllocensin k, 11beta-Hydroxygedunin, 6α,11-11β-diacetoxygedunin, Oleic Acid, Palmitic Acid, Stearic Acid, Arachidic Acid, Myristic Acid, Palmitoleic Acid, Linoleic Acid, Linolenic Acid, and Beenic Acid. Regarding physicochemical aspects, fatty acids violated LogP, and only limonoid 11 violated Lipinski’s rule. A common pharmacokinetic aspect was that all molecules were well absorbed in the intestine and inhibited CYP. All compounds showed toxicity in some model, with fatty acids being mutagenic and carcinogenic, and limonoids not being mutagenic and carcinogenic at least for rats. In in vivo models, fatty acids were less toxic. Molecular dockings were performed on COX-2 steroids (15 and 16) and hypoxia-inducible factor 1 alpha for limonoids (3,6), with this target being essential for the intracellular development of leishmania. Limonoids 3 and 6 appear to be promising as leishmanicidal agents, and fatty acids are promising as wound healers.

Objective To explore the changes of fatty acids levels in peripheral blood erythrocyte membrane and their relationships with the risk of endometrial cancer (EC). Methods Peripheral blood of fasting 91 EC patients (EC group) and 203 healthy volunteer women (control group) were collected. After erythrocyte cells were isolated, the levels of erythrocyte membrane fatty acids were detected by gas chromatograph-mass spectrum. The effect of changes of fatty acid levels on the risk of EC was analyzed. Results The compositions of fatty acids ranged from high level to low level in erythrocyte membrane of the EC group and control group were total saturated fatty acids (SFA), total polyunsaturated fatty acids (PUFA) and total monounsaturated Fatty Acids (MUFA). Compared with the control group, the total SFA level was higher and the total MUFA level was lower than those of the EC group (both P<0. 05), but there was no significant difference in the PUFA level between these two groups (P>0. 05). In SFA of the erythrocyte membrane, the levels of myristic acid C14：0, stearic acid C18：0, behenic acid C22：0 and lignoceric acid C24：0 in the EC group were higher than those of the control group, but the level of arachidic acid C20：0 was lower than that of the control group (all P<0. 05). In MUFA of the erythrocyte membrane, the levels of palmitoleic acid C16：1n7 and nervonic acid C24：1n9 were higher, but the level of oleic acid C18：1n9 was lower than those of the control group (all P<0. 05). In ω-6 PUFA of the erythrocyte membrane, the level of linoleic acid (LA) C18：2n6 was lower, but the levels of gamma-linoleic acid (GLA) C18：3n6, C20：2n6 and C20：3n6 were higher than those of the control group (all P<0. 05). In ω-3 PUFA of erythrocyte membrane, the level of α -linolenic acid (ALA) C18：3n3 was lower, but the ratio of arachidonic acid (AA)/docosahexaenoic acid (DHA) was higher than those of the control group (both P<0. 05). As shown by binary Logistic regression analysis, the increased levels of total SFA, myristic acid C14：0, behenic acid C22：0, lignoceric acid C24：0, palmitoleic acid C16：1n7, nervonic acid C24：1n9, and GLA increased the risk of EC (OR= 2. 14，2. 36，2. 60，3. 21，3. 25，4. 81 and 2. 74, respectively； all P<0. 05). Decreased levels of C20：0, C18：1n9, LA and ALA increased the risk of EC (OR=0. 38，0. 34，0. 21 and 0. 51, respectively； all P<0. 05). Conclusions The proportions of total SFA, myristic acid, behenic acid, lignoceric acid, palmitoleic acid C16：1n7, nervonic acid C24：1n9 and GLA increased in the EC patients, the proportions of arachidic acid C20：0, oleic acid C18：1n9, LA, and ALA decreased, and the changes in the above fatty acid proportions were related to the incidence of EC [ABSTRACT FROM AUTHOR]

Vital cellular processes depend on the controlled transport of metal ions across biological membranes. A biological membrane is a complex system consisting of lipids and proteins, that is why simplified systems, in particular monomolecular layers, are used to model it. This work presents the results of a study of the interaction of zinc ions from the aqueous subphase with the Langmuir monolayer of arachidic acid. The study was carried out for the first time and used total external reflection X-ray absorption spectroscopy. It considers the influence of the concentration of a ZnCl2 aqueous subphase solution on the local environment of zinc ions when interacting with the lipid monolayer immediately after its formation. The theoretical analysis of experimental XANES spectra showed that one of the interaction ways of arachidic acid molecules with zinc ions immediately after the monolayer formation is an intramolecular interaction with the formation of spodium bonds between the zinc cation and the OH carboxyl group of arachidic acid

Properties of the Langmuir-Blodgett (LB) films of arachidic and stearic acids, versus the amount of the films' monolayers were studied and applied for chloroform vapor detection with acoustoelectric high-frequency SAW sensors, based on an AT quartz two-port Rayleigh type SAW resonator (414 MHz) and ST-X quartz SAW delay line (157.5 MHz). Using both devices, it was confirmed that the film with 17 monolayers of stearic acid deposited on the surface of the SAW delay line at a surface pressure of 30 mN/m in the solid phase has the best sensitivity towards chloroform vapors, compared with the same films with other numbers of monolayers. For the SAW resonator sensing using slightly longer arachidic acid molecules, the optimum performance was reached with 17 LB film layers due to a sharper decrease in the Q-factor with mass loading. To understand the background of the result, Atomic Force Microscopy (AFM) in intermittent contact mode was used to study the morphology of the films, depending on the number of monolayers. The presence of the advanced morphology of the film surface with a maximal average roughness (9.3 nm) and surface area (29.7 µm2) was found only for 17-monolayer film. The effects of the chloroform vapors on the amplitude and the phase of the acoustic signal for both SAW devices at 20 °C were measured and compared with those for toluene and ethanol vapors; the largest responses were detected for chloroform vapor. For the film with an optimal number of monolayers, the largest amplitude response was measured for the resonator-based device. Conversely, the largest change in the acoustic phase produced by chloroform adsorption was measured for delay-line configuration. Finally, it was established that the gas responses for both devices coated with the LB films are completely restored 60 s after chamber cleaning with dry air. [ABSTRACT FROM AUTHOR]

A novel, single step and environment friendly solid state approach for reduction of graphene oxide (GO) monolayers has been demonstrated, in which, arachidic acid/GO/arachidic acid (AA/GO/AA) sandwich structure obtained by Langmuir-Blodgett (LB) technique was heat treated at moderate temperatures to obtain RGO sheets. Heat treatment of AA/GO/AA sandwich structure at 200 °C results in substantial reduction of GO, with concurrent removal of AA molecules. Such developed RGO sheets possess sp 2-C content of ∼69 %, O/C ratio of ∼0.17 and significantly reduced I(D)/I(G) ratio of ∼1.1. Ultraviolet photoelectron spectroscopy (UPS) studies on RGO sheets evidenced significant increase in density of states in immediate vicinity of Fermi level and decrease in work function after reduction. Bottom gated field effect transistors fabricated with isolated RGO sheets displayed charge neutrality point at a positive gate voltage, indicating p-type nature, consistent with UPS and electrostatic force microscopy (EFM) measurement results. The RGO sheets obtained by heat treatment of AA/GO/AA sandwich structure exhibited conductivity in the range of 2–7 S/cm and field effect mobility of 0.03–2 cm2/Vs, which are comparable with values reported for RGO sheets obtained by various chemical/thermal reduction procedures. The extent of GO reduction is determined primarily by proximity of AA molecules and found to be unaltered with either escalation of heat treatment temperature or increase of AA content in sandwich structure. The single-step GO reduction approach demonstrated in this work is an effective way for development of RGO monolayers with high structural quality towards graphene-based electronic device applications. [Display omitted] • First report on green and solid state reduction of graphene oxide monolayers • Reduction of GO facilitated by proximity of arachidic acid in sandwich structure • Development of RGO monolayers without generation of hazardous by-products/residues • RGO monolayer is of high structural quality and usable for electronic applications. • EFM, UPS, and electrical measurements confirm p-type behavior, superior electrical conductivity. [ABSTRACT FROM AUTHOR]

Rayleigh surface acoustic wave (RSAW)-based resonant sensors, functionalized with single and multiple monomolecular layers of Langmuir–Blodgett (LB) films, were thickness and density optimized for the detection of volatile organic compounds (VOC), which could impose a serious threat on the environment and human health. Single layers of a phospholipid (SLP), hexane dissolved arachidic acid (HDAA), and chloroform dissolved arachidic acid (CDAA) were used for the LB film preparation. Several layers of these compounds were deposited on top of each other onto the active surface of high-Q 434 MHz two-port RSAW resonators in a LB trough to prepare a highly sensitive vapor detection quartz surface microbalance (QSM). Frequency shift was measured with a vector network analyzer (VNA). These devices were probed with saturated vapors of hexane, chloroform, methanol, acetone, ethanol, and water after each deposited layer to test the behavior of the QSM's insertion loss, loaded Q, vapor sensitivity, and to find the optimum trade-off between these parameters for the best real-life sensor performance. With 2200 ppm and 3700 ppm sensitivity to chloroform, HDAA and CDAA coated QSM devices reached the optimum sensor performance at 15 and 11–15 monolayers, respectively. Surface pressure optimized single monolayers of phospholipid LB films were found to provide up to 530 ppm sensitivity to chloroform vapors with a negligible reduction in loss and loaded Q. This vapor sensitivity is higher than the mass of the sensing layer itself, making SLP films an excellent choice for QSM functionalization. [ABSTRACT FROM AUTHOR]

[Display omitted] Specific interactions of yttrium and lanthanum ions with a fatty acid Langmuir monolayer were investigated using vibrational sum frequency spectroscopy. The trivalent ions were shown to interact with the charged form of the carboxylic acid group from nanomolar concentrations (<300 nM). Analysis of the spectral features from both the symmetric and the asymmetric carboxylate modes reveals the presence of at least three distinct coordination structures linked to specific binding configurations. Although the same species were identified for both La3+ and Y3+, they display a different concentration dependence, highlighting the ion-specificity of the interaction. From the analysis of the response of interfacial water molecules, the reversal of the surface charge, as well as the formation of yttrium hydroxide complexes, were detected upon increasing the amount of salt in solution. The binding interaction and kinetics of absorption are sensitive to the solution pH, showing a distinct ion speciation in the interfacial region when compared to the bulk. Changing the subphase pH or adding a monovalent background electrolyte that promotes deprotonation of the carboxylic acid headgroup could further improve the detection limit of La3+ and Y3+ to concentrations < 100 nM. These findings demonstrate that nM concentrations of trace metals contaminants, typically found on monovalent salts, can significantly influence the binding structure and kinetics in Langmuir monolayers. [ABSTRACT FROM AUTHOR]

The oil of Carapa guianensis showed leishmanicidal activity, with its activity being related to limonoids, but fatty acids are the major constituents of this oil. The present study evaluated the physicochemical, pharmacokinetic, and toxicity profiles of limonoids and fatty acids already identified in the species. Based on these results, 2 limonoids (methyl angosinlate, 6-OH-methyl angosinlate) and 2 fatty acids (arachidic acid; myristic acid) were selected for the prediction of possible targets and molecular docking. Included in this study were: Gedunin, 6α-acetoxygedunin, Methyl angosenlato, 7-deacetoxy-7-oxogedunin, Andirobin, 6-hydroxy-angolensate methyl, 17β-hydroxyazadiradione, 1,2-dihydro-3β-hydroxy-7-deacetoxy-7-oxogedunin, xyllocensin k, 11beta-Hydroxygedunin, 6α,11-11β-diacetoxygedunin, Oleic Acid, Palmitic Acid, Stearic Acid, Arachidic Acid, Myristic Acid, Palmitoleic Acid, Linoleic Acid, Linolenic Acid, and Beenic Acid. Regarding physicochemical aspects, fatty acids violated LogP, and only limonoid 11 violated Lipinski's rule. A common pharmacokinetic aspect was that all molecules were well absorbed in the intestine and inhibited CYP. All compounds showed toxicity in some model, with fatty acids being mutagenic and carcinogenic, and limonoids not being mutagenic and carcinogenic at least for rats. In in vivo models, fatty acids were less toxic. Molecular dockings were performed on COX-2 steroids (15 and 16) and hypoxia-inducible factor 1 alpha for limonoids (3,6), with this target being essential for the intracellular development of leishmania. Limonoids 3 and 6 appear to be promising as leishmanicidal agents, and fatty acids are promising as wound healers., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2024 de Barros, Araujo da Costa, Farias, de Albuquerque, Marinho, Campos, Marinho and Dolabela.)

Properties of the Langmuir-Blodgett (LB) films of arachidic and stearic acids, versus the amount of the films’ monolayers were studied and applied for chloroform vapor detection with acoustoelectric high-frequency SAW sensors, based on an AT quartz two-port Rayleigh type SAW resonator (414 MHz) and ST-X quartz SAW delay line (157.5 MHz). Using both devices, it was confirmed that the film with 17 monolayers of stearic acid deposited on the surface of the SAW delay line at a surface pressure of 30 mN/m in the solid phase has the best sensitivity towards chloroform vapors, compared with the same films with other numbers of monolayers. For the SAW resonator sensing using slightly longer arachidic acid molecules, the optimum performance was reached with 17 LB film layers due to a sharper decrease in the Q-factor with mass loading. To understand the background of the result, Atomic Force Microscopy (AFM) in intermittent contact mode was used to study the morphology of the films, depending on the number of monolayers. The presence of the advanced morphology of the film surface with a maximal average roughness (9.3 nm) and surface area (29.7 µm2) was found only for 17-monolayer film. The effects of the chloroform vapors on the amplitude and the phase of the acoustic signal for both SAW devices at 20 °C were measured and compared with those for toluene and ethanol vapors; the largest responses were detected for chloroform vapor. For the film with an optimal number of monolayers, the largest amplitude response was measured for the resonator-based device. Conversely, the largest change in the acoustic phase produced by chloroform adsorption was measured for delay-line configuration. Finally, it was established that the gas responses for both devices coated with the LB films are completely restored 60 s after chamber cleaning with dry air.

The temperature of an electronic device is one of the most important parameters to deal with. Any increase above the temperature limits results in a failure in the device. Thus, to ensure good operation, an electronic device should be cooled. One promising technique is the use of Phase Change Materials (PCMs) for their well-known ability to absorb the heat dissipated by the device, thanks to their high latent heat of fusion. Arachidic acid is a fatty acid that, when mixed with sodium decanoate and potassium oleate salts, can be used as a promising PCM due to its high latent heat. This paper aims to shed light on the use such mixtures of Arachidic acid for cooling in a heat sink. An experimental setup was built for this purpose. The results show that the Arachidic acid mixtures are suitable for applications requiring intermediate heat dissipation. [ABSTRACT FROM AUTHOR]

The study aimed to evaluate in vivo fertility of cryopreserved buffalo spermatozoa by addition of arachidic acid in semen extender. For this purpose, semen was collected from 3 adult buffalo bulls (Bubalus bubalis) of same age by artificial vagina keeping temperature at 42°C for a period of 5 weeks (replicates; n=30). Ejaculates were mixed in tris citric acid extender having 0.0 (control), 20.0, 25.0 and 30.0 ng/mL of arachidic acid at a temperature of 37°C (>1 mL volume, >0.5 billion per mL conc., >60% motility) and cryopreserved using standard procedures. Percent sperm motility, liveability, plasmalemma integrity and viability were increased in extender (P<0.05) having 20.0 ng/mL of arachidic acid compared to 25.0 ng/mL, 30.0 ng/mL and control. However, sperm chromatin integrity was equally improved in experimental extenders having arachidic acid compared to control. Sperm abnormalities were reduced in experimental extender with 20 ng/mL of arachidic acid compared to other experimental extenders containing arachidic acid and control. In experiment 2, a total of 533 inseminations were carried out by the extender containing best level of arachidic acid (20 ng/mL of extender). In vivo fertility was significantly improved in buffaloes inseminated with semen containing 20.0 ng/mL of arachidic acid (58.64%) compared to control (46.06%). In conclusion, addition of arachidic acid (20.0 ng/mL) in extender significantly enhanced quality and in vivo fertility of post thaw buffalo semen. [ABSTRACT FROM AUTHOR]

• Fatty acids are potential candidates to be used as Phase Change Materials in solar applications. • Arachidic acid is an interesting fatty acid for its thermal properties namely the latent of fusion. • Mixing the acid with impurities strengthen its potential by lowering its melting point with a high latent. • Mixture with 10 mol% of sodium decanoate led to an onset T of 48 °C and latent of 222 J/g suitable for solar water heating. The use of natural materials especially fatty acids as phase change materials (PCM) for different applications is considered as a current challenge for the scientific community. The main advantages of fatty acids are that they cover a wide range of melting temperatures and consume a good amount of latent heat while transiting from a state of aggregation to another. This work focuses on Arachidic acid, a fatty acid which presents some remarkable thermal properties that enable its use as PCM. Arachidic acid is mixed with different chemical salts in a cost-efficient manner, in order to alter its thermal characteristics. The main objective of the modifications is to maintain high latent heat, with a wider span of melting temperature and a smaller melting peak temperature to accommodate with the allowable electronic devices' temperatures. Specific properties such a s the heat capacity, the new latent heat (J/g), and peak temperature (°C) were determined in order to analyze the reliability and stability of fatty acids as PCM. The results showed that Arachidic acid mixed with 10 mol% sodium decanoate exhibited the highest melting point depreciation, from 75.2 °C to 71.9 °C, while maintaining a high latent heat of fusion (222 J/g). [ABSTRACT FROM AUTHOR]

Background: Very-long-chain SFAs (VLCSFAs), such as arachidic acid (20:0), behenic acid (22:0), and lignoceric acid (24:0), have demonstrated inverse associations with cardiometabolic conditions, although more evidence is needed to characterize their relation with risk of type 2 diabetes (T2D). In addition, little is known regarding their potential dietary and lifestyle predictors.Objective: We aimed to examine the association of plasma and erythrocyte concentrations of VLCSFAs with incident T2D risk.Methods: We used existing measurements of fatty acid concentrations in plasma and erythrocytes among 2854 and 2831 participants in the Nurses' Health Study (NHS) and Health Professionals Follow-Up Study (HPFS), respectively. VLCSFAs were measured using GLC, and individual fatty acid concentrations were expressed as a percentage of total fatty acids. Incident T2D cases were identified by self-reports and confirmed by a validated supplementary questionnaire. Cox proportional hazards regression was used to evaluate the association between VLCSFAs and T2D, adjusting for demographic, lifestyle, and dietary variables.Results: During 39,941 person-years of follow-up, we documented 243 cases of T2D. Intakes of peanuts, peanut butter, vegetable fat, dairy fat, and palmitic/stearic (16:0-18:0) fatty acids were significantly, albeit weakly, correlated with plasma and erythrocyte VLCSFA concentrations (|rs| ≤ 0.19). Comparing the highest with the lowest quartiles of plasma concentrations, pooled HRs (95% CIs) were 0.51 (0.35, 0.75) for arachidic acid, 0.43 (0.28, 0.64) for behenic acid, 0.40 (0.27, 0.61) for lignoceric acid, and 0.41 (0.27, 0.61) for the sum of VLCSFAs, after multivariate adjustments for demographic, lifestyle, and dietary factors. For erythrocyte VLCSFAs, only arachidic acid and behenic acid concentrations were inversely associated with T2D risk.Conclusions: Our findings suggest that, in US men and women, higher plasma concentrations of VLCSFAs are associated with lower risk of T2D. More research is needed to understand the mechanistic pathways underlying these associations. [ABSTRACT FROM AUTHOR]

The temperature of an electronic device is one of the most important parameters to deal with. Any increase above the temperature limits results in a failure in the device. Thus, to ensure good operation, an electronic device should be cooled. One promising technique is the use of Phase Change Materials (PCMs) for their well-known ability to absorb the heat dissipated by the device, thanks to their high latent heat of fusion. Arachidic acid is a fatty acid that, when mixed with sodium decanoate and potassium oleate salts, can be used as a promising PCM due to its high latent heat. This paper aims to shed light on the use such mixtures of Arachidic acid for cooling in a heat sink. An experimental setup was built for this purpose. The results show that the Arachidic acid mixtures are suitable for applications requiring intermediate heat dissipation.

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Very long-chain saturated fatty acids (VLSFAs) are saturated fatty acids with 20 or more carbons. In contrast to the more abundant saturated fatty acids, such as palmitic acid, there is growing evidence that circulating VLSFAs may have beneficial biological properties. Whether genetic factors influence circulating levels of VLSFAs is not known. We investigated the association of common genetic variation with plasma phospholipid/erythrocyte levels of three VLSFAs by performing genome-wide association studies in seven population-based cohorts comprising 10,129 subjects of European ancestry. We observed associations of circulating VLSFA concentrations with common variants in two genes, serine palmitoyl-transferase long-chain base subunit 3 (SPTLC3), a gene involved in the rate-limiting step of de novo sphingolipid synthesis, and ceramide synthase 4 (CERS4). The SPTLC3 variant at rs680379 was associated with higher arachidic acid (20:0 , P = 5.81 × 10−13). The CERS4 variant at rs2100944 was associated with higher levels of 20:0 (P = 2.65 × 10−40) and in analyses that adjusted for 20:0, with lower levels of behenic acid (P = 4.22 × 10−26) and lignoceric acid (P = 3.20 × 10−21). These novel associations suggest an inter-relationship of circulating VLSFAs and sphingolipid synthesis.

Abstract: Toll‐like receptors (TLRs) induce an innate immune system. In general, there are two main pathways in TLRs: the myeloid differentiation primary response protein 88 (MyD88)‐dependent and toll‐interleukin‐1 receptor domain‐containing adapter‐inducing interferon‐β (TRIF)‐dependent pathways. In this study, it has been investigated whether eicosapentaenoic acid (EPA), a polyunsaturated fatty acid (PUFA), and arachidic acid (ACA), a saturated fatty acid (SFA), can modulate the TLR signaling pathways. EPA suppressed the activation of interferon regulatory factor 3 (IRF3) and the expression of Interferon gamma‐induced protein (IP‐10) induced by Toll‐like receptor 3 (TLR3) or TLR4 agonists by targeting TANK‐binding kinase 1 (TBK1); however, ACA did not. These results demonstrate that EPA inhibits the TRIF‐dependent signaling in the TLR3 and TLR4 pathways. The results raise the possibility that certain dietary PUFAs can modulate TLR‐derived signaling and inflammatory target gene expression and can alter the susceptibility to microbial infection and chronic inflammatory diseases. Practical application: Eicosapentaenoic acid (EPA) is a bioactive lipid that modulates inflammation and immunity. TLRs play a central role as initiators of the innate immune responses. EPA regulates TRIF‐dependent pathways of TLRs by targeting TBK1. EPA may be a useful strategy to understand the mechanism of antiinflammatory activities. [ABSTRACT FROM AUTHOR]

Toll-like receptors (TLRs) play critical roles in the induction of immune and inflammatory responses by recognizing invading microbial pathogens. One of the most important proteins for inflammatory responses is inducible nitric oxide synthase (iNOS). The dysregulated iNOS activation play important roles in the development of certain inflammatory diseases. The present study investigated the effects of arachidic acid (ACA), which is a saturated fatty acid (SFA), and eicosapentanoic acid (EPA), which is polyunsaturated fatty acid (PUFA), on inflammation by modulating NF-κB activation and iNOS expression induced by TLRs agonists in murine macrophages. EPA suppressed NF-κB activation and iNOS expression induced by a lipopolysaccharide, macrophage-activating lipopeptide 2-kDa, and polyriboinosinic polyribocytidylic acid, but ACA did not. These results suggested that EPA can modulate TLR signaling pathways and subsequent chronic inflammatory responses, but ACA did not mediate these effects. All the results suggest that EPA is a promising novel agent for the treatment of inflammatory diseases. [ABSTRACT FROM AUTHOR]

Background and Aims Powdery mildew ( Erysiphe necator) reduces the quality of winegrapes, and objective methods for assessment are required. Mid-infrared spectroscopy and fatty acid analysis were investigated for rapid diagnosis of affected berries. Methods and Results Colonisation by E. necator reduced berry diameter and mass and increased the surface area : volume ratio. Mid-infrared spectra (1800-1185 cm−1) contained information on E. necator and compounds related to infection, but spectral similarity of visually healthy and partly infected berries confounded differentiation between these groups. Fatty acids in E. necator and berries were identified and quantified by gas chromatography. Six saturated even-chain fatty acids were prevalent in E. necator, arachidic acid being most abundant. Following stepwise linear discriminant analysis, four saturated fatty acids distinguished 97% of healthy berries and assigned approximately 75% of partly and fully infected berries to their original groups. Arachidic acid concentration, which changed amongst healthy, partly and fully infected berries ( P = 0.001), correctly classified 90% of healthy berries. Conclusions Analysis of fatty acids allowed discrimination of healthy and infected berries whereas mid-infrared spectroscopy proved less informative. Arachidic acid concentration increased with disease severity. Significance of the Study Fatty acid analysis offers a new approach for objective measurement of powdery mildew. Arachidic acid is proposed as a biomarker for powdery mildew on grapes. [ABSTRACT FROM AUTHOR]

Purpose: We aimed to characterize common genetic variants that influence saturated fatty acid concentrations in East Asians. Methods: Meta-analysis of genome-wide association studies for circulating SFAs was conducted in two population-based cohorts comprising 3521 participants of Chinese ancestry. Results: We identified two novel 14:0-associated loci at LMX1A (LIM homeobox transcription factor 1) and AMPD3 (AMP deaminase 3) ( P = 5.08 × 10 and P = 4.33 × 10, respectively), and a novel 20:0-associated locus at CERS4 (ceramide synthase 4) ( P = 1.76 × 10). We also confirmed the previously reported association of FADS1/2-rs102275 with 18:0 ( P = 1.12 × 10). In addition, the A alleles of rs11042834 in AMPD3 and rs17159388 in CERS4 also exhibited evidence of associations with high-density lipoprotein cholesterol ( P = 0.0162 and P = 0.0161, respectively). Conclusions: To our knowledge, this is the first GWAS analysis to examine SFA concentrations in East Asian populations. Our findings provide novel evidence that genetic variations of several genes from multiple pathways are associated with SFA concentrations in human body. [ABSTRACT FROM AUTHOR]

This paper considers some approaches to the technology of the synthesis of a graphene monolayer at a phase interface. A surfactant monolayer on an aqueous subphase is proposed as the substrate for graphene synthesis. A monolayer is formed by the Langmuir-Blodgett method. Simple polyaromatic molecules, in particular, naphthalene, are considered as the basic substance for the synthesis of graphene. Arachidic acid is used as the basic surfactant molecule. To confirm the possibility of synthesizing graphene by the mentioned method, both experimental and theoretical studies are performed. In the course of experiemnts, it is shown that naphthalene molecules are pressed into the space above arachidic acid molecules upon the compression of monolayer of arachidic acid-naphthalene mixtures (such an assumption is made due to the characteristic value of the surface areas attributed to different phases of the monolayer and also to its characteristic parameters). The formation of a layer of naphthalene molecules on the surface of a monolayer is modeled by the molecular dynamics method (Amber potential). Different variants of the initial distribution of molecules are considered. [ABSTRACT FROM AUTHOR]

The photocatalytic process of arachidic acid decomposition on titanium dioxide in the form of polycrystalline anatase and on titanium dioxide modified by silver nanoparticles (AgNPs/TiO 2 ) was observed using atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR). Arachidic acid (AA) was chosen as a model pollutant because its molecules have an ability to organize in the form of Langmuir – Blodgett monolayers on a water/air interface and, subsequently, may be transferred onto the surface of TiO 2 and AgNPs/TiO 2 coatings. Such a system is easily observable by AFM technique. As expected, titanium dioxide coatings induced the photocatalytic degradation of AA under UV illumination, however, in the presence of AgNPs this process ran either more rapidly or slower. The decomposition of AA proceeded through the continuous disappearance of AA layers while preserving the layer thickness. The received results allowed us to reach a conclusion about the mechanism which occurred during AA photodegradation on both types of coatings. It was suggested that the process was initiated in active surface sites and subsequently propagated until the whole amount of AA was decomposed. The linear dependence of the surface coverage vs. the time of illumination showing the degradation rate of AA layers indicates a zero kinetics order of reaction. [ABSTRACT FROM AUTHOR]