Isolation of 6,9,12,15-Hexadecatetraenoic Fatty Acid (16:4n-1) Methyl Ester from Transesterified Fish Oil by HSCCC

Fish oil is considered a healthy food due to the presence of large amounts of polyunsaturated fatty acids (PUFAs), especially in the form of n-3 fatty acids 5,8,11,14,17-eicosapentaenoic acid (20:5n-3; EPA) and 4,7,10,13,16,19-docosahexaenoic acid (22:6n-3; DHA). However, fish oil is known to contain many other PUFAs, some of which are uncommon and whose bioactivity is scarcely investigated. In this study, we isolated the rare PUFA 6,9,12,15-hexadecatetraenoic fatty acid (16:4n-1) which bears a double bond on the terminal carbon from fish oil in form of its methyl ester. We used high-speed counter-current chromatography (HSCCC) for the fractionation of 500 mg-portions of fatty acid methyl esters prepared from a fish oil capsule and investigated the fractions by GC/MS. Twenty-eight 13-mL fractions were collected and fatty acid methyl esters were detected in fractions 11–23. The elution was carried out in normal phase mode, providing the long-chained saturated and monoenoic fatty acids first. More than 100 fatty acids ranging from 10:0 to 26:0 could be identified in the HSCCC fractions, and most of them were polyunsaturated. The reproducibility of the HSCCC method was shown by repeated injection of the fish oil and the fractions containing 6,9,12,15-hexadecatetraenoic fatty acid (16:4n-1). The late eluting 16:4n-1 methyl ester was isolated in pure form and its structure was verified.

     

Optimization of Fatty Acid Determination in Selected Fish and Microalgal Oils

The use of ten fatty acid methyl ester reference standards coupled with a detailed quantification method was shown to significantly optimize the fatty acid determination of selected fish and microalgal oils when compared to methods that use only one reference standard (C19:0 or C23:0) as a relative response factor. When using the mixture of ten reference standards after transesterifying oils with NaOH/BF₃, determination of total fatty acids, eicosapentaenoic acid and docosahexaenoic acid improved by an average of 7.3, 11.5 and 8.4%, respectively. Furthermore, improvements of 13.9, 18.9 and 6.8% of total fatty acids, EPA and DHA, respectively, were obtained when using the mixture of reference standards for fatty acid determination after directly extracting and transesterifying oil contained in microalgal cells with a mixture of methanol, HCl and chloroform. Fatty acid methyl ester standards dissolved in isooctane showed <5% variability throughout 130 days of stability testing when stored at ?20 °C. The optimized method can be used for improving the quantification of fatty acids in both oils (fish and microalgal oils) and dry microalgal cells.     

Antioxidant,Antimicrobial Activities and Fatty Acid Compositions of Wild Berberis spp. by Different Techniques Combined with Chemometrics (PCA and HCA)

Interest in medicinal plants and fruits has increased in recent years due to people beginning to consume natural foods. This study aims to investigate the total phenolic flavonoid content, antioxidant activity, condensed tannin content, oil content, and fatty acid compositions of five local breeds of Berberis spp. from Bayburt, Turkey, and their antioxidant and antimicrobial activities. The fatty acid composition of samples was performed with gas chromatography-mass spectrometry (GC-MS), and the total fatty acid content of samples was between 6.12% and 8.60%. The main fatty acids in Berberis spp. samples were α-linolenic acid (32.85–37.88%) and linoleic acid (30.98–34.28%) followed by oleic acid (12.85–19.56%). Two antioxidant assays produced similar results, demonstrating that extracts of wild B. vulgaris L. had the highest ferric reducing antioxidant power (FRAP) (621.02 μmol FeSO₄.7H₂O/g) and 1,1-diphenyl-2-picrylhydrazyl radical (DPPH) (0.10 SC₅₀ mg/mL) values. According to principal component analysis (PCA), four components were determined. In addition, two main groups were determined according to hierarchical cluster analysis (HCA), and wild and culture of B. vulgaris L. were in different subgroups. This is the first original report about the fatty acid composition and oil content of Berberis spp. grown in Bayburt, Turkey. The obtained results indicate that B. integerrima Bunge and B. vulgaris, which have especially remarkable fatty acid content, antioxidant, and antimicrobial activity, could be potential sources for these properties in different areas of use.     

Surface Activity of Fatty Acid Salts in Aqueous Solutions

The surface activity of sodium, potassium and, ammonium salts of fatty acids [stearic, oleic, synthetic fatty acids (C_{1 3}-C_{1 5} fractions), higher fatty acids contained in bottoms after separation of volatile fatty acids from cotton oil] in aqueous solutions was studied and analyzed.     

GC Analysis of the Fatty Acid Composition of Yak Kidney

To obtain valuable information for development of potential commercial products from yak kidney, which is usually treated as waste, the fatty acid composition of kidneys from yak reared in Gansu province, China, was investigated by gas chromatography. Fifteen different fatty acids were identified. The major fatty acids are oleic acid (33.3%), stearic acid (20.2%), and palmitic acid (18.4%). More interestingly, several important and essential fatty acids were also identified, including conjugated linoleic acid (2.94%), omega-3 fatty acids, for example docosahexaenoic acid (1.47%), eicosapentaenoic acid (1.11%) and alpha linolenic acid (0.37%), and omega-6 fatty acids, for example arachidonic acid (2.86%) and linoleic acid (1.98%). The results show that the fatty acid composition of yak kidney is of reasonable value and is suitable for further development of possible commercial products. This is the first report of the fatty acid profile of yak kidney.

     

Effect of Irrigation on the Oil Content and Fatty Acid Composition of Some Sunflower Seeds

The effect of irrigation on the seed yield, oil yield, and oil composition of sunflower in populations of Ekiz1 and VNIIMK 8931, a mixture of N₂, N₃, and N₄ lines, and a synthetic variety obtained from these lines has been studied. The major fatty acid was found to be oleic acid, in addition to linoleic, palmitic, and stearic acids. Irrigation increased seed yield, oil yield, and oil content of all samples. In two of them, the synthetic variety and VNIIMK 8931, the increase was found to be statistically significant. In addition, irrigation of the samples did not increase significantly the amount of oleic and linoleic acids. On the contrary, the amount of linoleic acid in the mixture of N₂, N₃, and N₄ lines and oleic acid in VNIIMK 8931 decreased statistically significantly.     

Epoxidation of Polyunsaturated Fatty Acid Double Bonds by Dioxirane Reagent: Regioselectivity and Lipid Supramolecular Organization

The use of dimethyldioxirane (DMD) as the epoxidizing agent for polyunsaturated fatty acids was investigated. With fatty acid methyl esters, this is a convenient method for avoiding acidic conditions, using different solvents, and simplifying the isolation procedures, with less contamination due to by‐products. The reagent was also tested with free fatty acids in water. In this case, the supramolecular organization of fatty acids influenced the reaction outcome, and the epoxidation showed interesting regioselective features. The C?C bonds closest to the aqueous‐micelle interface is the most favored for the interaction with dimethyldioxirane. The preferential epoxidation of linoleic acid (= (9Z,12Z)‐octadeca‐9,12‐dienoic acid) to the 9,10‐monoepoxy derivative was achieved, with a high yield and 65% regioselectivity. In case of arachidonic acid (= (5Z,8Z,11Z,14Z)‐eicosa‐5,8,11,14‐tetraenoic acid) micelles, the regioselective outcome with formation of the four possible monoepoxy isomers was studied under different conditions. It resulted to be a convenient synthesis of ‘cis‐5,6‐epoxyeicosatrienoic acid’ (= 3‐[(2Z,5Z,8Z)‐tetradeca‐2,5,8‐trienyl]oxiran‐2‐butanoic acid), whereas in reverse micelles, epoxidation mostly gave ‘cis‐14,15‐epoxyeicosatrienoic acid (= (5Z,8Z,11Z)‐13‐(3‐pentyloxiran‐2‐yl)trideca‐5,8,11‐trienoic acid).     

Analysis of the Dynamic Decomposition of Unsaturated Fatty Acids and Tocopherols in Commercial Oils During Deep Frying

The decomposition of unsaturated fatty acids and tocopherols in 10 commercial edible oils during deep frying was investigated. The dominant tocopherol in oils rich in polyunsaturated fatty acids (PUFAs) was γ-tocopherol, except for natural perilla oil (δ-tocopherol dominant), and the main tocopherol in oleic acid-rich oils was α-tocopherol. The PUFA-rich oils had higher tocopherol contents than the oleic acid-rich oils. Both the reduction rate of total unsaturated fatty acid (TUFA) and total tocopherol (TToc) were linear with frying time (t). The decomposition rate of TToc is faster than that of TUFA since the slope values obtained from fitting equations (Y?=?k t) k_TToc (1.520–14.483) were obviously larger than for k_TUFA (0.155–0.270). By establishing a dynamic decomposition index, unsaturated fatty acids and tocopherol in oils showed dynamic decomposition over multiple frying cycles. The obtained results showed that decomposition characteristics of oils are related to their fatty acid compositions.     

Fatty Acid Composition of Tobacco Seed Oil and Synthesis of Alkyd Resin

The fatty acid composition of tobacco seed oil revealed that the oil is rich in unsaturated fatty acids, having linoleic acid （71.63%）, oleic acid （13.46%） and palmitic acid （8.72%） as the most abundant unsaturated and saturated fatty acids respectively. So the tobacco oil was characterized as semi-drying type on the basis of fatty acid composition. The synthesis of alkyd resin was carried out by alcoholysis or monoglyceride process using an alkali refined tobacco seed oil, pentaerythritol, cis-1,2,3,6-tetrahydrophthalic anhydride along with lithium hydroxide as catalyst. The alkyd resin so prepared was found to be bright and of low color with high gloss. The drying and hardness properties and adhesion of the tobacco seed oil derived alkyd resin were also found a bit superior to those of other alkyd resins of the same oil length. In addition, the water and acid resistance of the said alkyd was also found comparable to the other alkyds.     

高效液相色谱-质谱分离鉴定荧光试剂标记的脂肪酸

以2-(2-(10-蒽基)-萘[2,3-d]咪唑)-乙基-对甲苯磺酸酯(ANITS)作为柱前衍生化试剂,在Eclipse XDB-C8色谱柱上,梯度洗脱实现了20种游离脂肪酸(FFA)衍生物的完全基线分离。90℃下在DMF溶剂中以K2CO3作催化剂,选取衍生试剂摩尔数为脂肪酸的7倍,衍生反应40min可获得稳定的荧光产物。激发和发射波长分别为250nm和512nm。采用大气压化学电离源(APCI)正离子模式,实现了油菜蜂花粉中游离脂肪酸的质谱鉴定。所有脂肪酸的线性相关系数均大于0.9999,检出限为24.76~98.79fmol。     

Gibberellic acid production by solid-state fermentation in coffee husk

Five strains of Gibberella fujikuroi and one of Fusarium moniliforme were screened for the production of gibberellic acid (GA₃) in coffee husk, and based on the results, one strain, G. fujikuroi LPB-06, was selected. The comparative production of GA₃ by solid-state fermentation and submerged fermentation indicated better productivity with the former technique, mainly with pretreated substrate. The GA₃ accumulation was 6.1 times higher in the case of solid-state fermentation. Considering the C:N relation, higher yields of GA₃ were achieved using a mixed substrate comprising coffee husk and cassava bagasse (7:3, dry wt), increasing the results twice. Supplementation of an optimized saline solution containing 0.03% FeSO₄ and 0.01% (NH₄)₂SO₄ enhanced the accumulation of GA₃ 1.7 times in the fermented substrate. Under the finally optimized condition, the culture gave a maximum of 492.5 mg of GA₃/kg of dry substrate, with a pH of 5.3, moisture of 75%, and incubation temperature of 29°C. GA₃ yield was almost 13 times more than the initial results.     

Determination of 30 Free Fatty Acids in Two Famous Tibetan Medicines by HPLC with Fluorescence Detection and Mass Spectrometric Identification

A simple and sensitive high-performance liquid chromatographic (HPLC) method with fluorescence detection and mass spectrometric identification has been developed for analysis of 30 long-chain and short-chain free fatty acids (FFAs). The fatty acids were derivatized to their esters with 1-[2-(p-toluenesulfonate)ethyl]-2-phenylimidazole-[4,5-f]-9,10-phenanthrene (TSPP) in N,N-dimethylformamide (DMF) at 90 °C with anhydrous K₂CO₃ as catalyst. A mixture of C₁–C₃₀ fatty acids was completely separated within 60 min by gradient elution on a reversed-phase C₈ column. Qualitative identification of the acids was performed by atmospheric-pressure chemical ionization mass spectrometry (APCI–MS) in positive-ion mode. The fluorescence excitation and emission wavelengths were 260 and 380 nm, respectively. Quantitative determination of the 30 acids in two Tibetan medicines Gentiana straminea and G. dahurica was performed. The results indicated that the medicines contained many FFAs. Linear correlation coefficients for the FFA derivatives were >0.9991. Relative standard deviations (RSDs, n = 6) for the fatty acid derivatives were <3%. Detection limits (at a signal-to-noise ratio of 3:1) were 3.1–38 fmol. When the fatty acid derivatives were determined in the two real samples results were satisfactory and the sensitivity and reproducibility of the method were good.     

Analysis of Free Fatty Acids on the Fingertips by High Performance Liquid Chromatography

Abstract

This investigation studied the efficiency of high performance liquid chromatography in the determination of free fatty acids present on the fingertips, and assessed the quantitative relationship between skin fatty acids and the degree of microbial contamination. Automated surgical scrub was utilized to eliminate the microbial contamination.

The high performance liquid chromatography provided excellent separation of skin fatty acids for evaluation with the bacterial counts. The fatty acid peaks identified ranged in chain length from C12 through C32. All the fatty acids evaluated showed positive correlation with the bacterial counts with the exception of one acid which had an inverse relationship but none were statistically significant. Finally, the surgical scrub chromatograms showed that the straight chain acids C19 and C21 were lower in concentration than C23 and C25; also, C26 was lower in concentration than C28 and C30.

It was evident from the data that fatty acids which have been shown to be bacteriostatic in vitro do not demonstrate the same property on the fingertips. The finding of lower concentration of C19, C21, and C26 than longer chain acids is inconsistent with simple two carbon addition, and indicates there is possible branching at these points in metabolic pathway of fatty acid synthesis.     

Seed Oil Fatty Acids of Mongolian Compositae: The trans‐Fatty Acids of Heteropappus hispidus,Asterothamnus centrali‐asiaticus and Artemisia palustris

Seed oils from the Compositae plant family are known to contain a variety of unusual fatty acids. Subsequent to the recent discovery of γ‐linolenic acid in Saussurea and Youngia, further Mongolian Compositae species were investigated for their seed oil fatty acid composition. A number of δ3trans‐fatty acids (16 : 1δ3t, 18 : 1δ3t and 18 : 3δ3t, 9c, 12c) were found in the seed oils of Heteropappus hispidus and Asterothamnus centrali‐asiaticus. The latter fatty acid, but not the trans‐monoenes, was also found in one species of Artemisia. These unusual fatty acid isomers were characterized by capillary gas‐liquid chromatographic (GLC) separations in combination with other chromatographic techniques (analytical thin layer chromatography, TLC and preparative argentation TLC), and infrared spectrocsopy (IR). Their identity was further confirmed by co‐chromatography with other seed oils known to contain these trans‐fatty acids. The fact that within the Compositae plant family there are apparently two or three distinct groups of genera containing δ3trans‐fatty acids is discussed.     

Long Chain Fatty Acid Affects Excited State Branching in Bilirubin-Human Serum Protein Complex?

After binding to human serum albumin, bilirubin could undergo photo-isomerization and photo-induced cyclization process. The latter process would result the formation of a product, named as lumirubin. These photo induced behaviors are the fundamental of clinical therapy for neonatal jaundice. Previous studies have reported that the addition of long chain fatty acids is beneficial to the generation of lumirubin, yet no kinetic study has revealed the mechanism behind. In this study, how palmitic acid affects the photochemical reaction process of bilirubin in Human serum albumin (HSA) is studied by using femtosecond transient absorption and fluorescence up-conversion techniques. With the addition of palmitic acid, the excited population of bilirubin prefers to return to its hot ground state (S₀) through a 4 ps decay channel rather than the intrinsic ultrafast decay pathways (< 1 ps). This effect prompts the Z-Z to E-Z isomerization at the S$_0$ state and then further increases the production yield of lumirubin. This is the first time to characterize the promoting effect of long chain fatty acid in the process of phototherapy with femtosecond time resolution spectroscopy and the results can provide useful information to benefit the relevant clinical study.     

Self‐Assembled Monolayer of L‐Cysteine on a Gold Electrode as a Support for Fatty Acid. Application to the Electroanalytical Determination of Unsaturated Fatty Acid

This article describes the formation of a SAM with chemisorbed cysteine to a gold surface by the thiol group to obtain a surface electrode with an amino and an acid group free for later reaction and accumulation with other molecules on the electrode surface. We explore the accumulation of unsaturated fatty acid and the electrochemical response of the electrode after modification with cysteine. The electrochemical study confirmed the accumulation of linoleic acid on the modified electrode. The optimum conditions for the determination of linoleic acid by differential pulse voltammetry of linoleic acid are studied a detection limit (3σ) of 0.03 μg mL^?1 and a determination limit (10σ) of 0.10 μg mL^?1 were obtained and applied to determination in olive oil and ham from Iberian breed hams.     

Analytical Characterization of Fatty Acids Composition of Datura alba Seed Oil by Gas Chromatography Mass Spectrometry

Methyl ester derivatives of fatty acids were analyzed for the determination of the constituents of Datura alba seed oil. Gas chromatography coupled to mass spectrometer was used for these analyses. Results delivered that there were saturated as well as unsaturated fatty acids in Datura alba seed oil. Total of 15 different fatty acid components were identified and quantified. Methyl linoleate was found in highest concentration (16.22%) among the identified analytes of interest. In addition methyl esters of Palmitic acid (6.59%), Oleic acid (5.41%) and Stearic acid (1.35%) were found. Concentrations of rest of the detected fatty acids were less than 1%. From the literature it appears that no such work has been performed for the determination of fatty acids in Datura alba seed oil.     

Analytical Characterization of Fatty Acids Composition of Bioactive Stem Oil of Maytenus royleanus by Gas Chromatography Mass Spectrometry

The significant inhibition and selectivity for human solid tumor cell by oily fraction of Maytenus royleanus, was subjected to GC‐MS analysis for determination of its chemical constituents. GC‐MS profile of methyl ester derivatives of fatty acids, showed that Palmitic acid (35.41%), Oleic acid (10.91%), Stearic acid (5.31%), Margaric acid (5.13%), Behenic acid (5.18%) and Hexanoic acid (4.97%) were the major components in the isolated oily fraction, while rest of the other fatty acids were present in minor concentration. The literature revealed that no such work has been done for the determination of fatty acids in M. royleanus stem oil.     

Investigation of Fatty Acid Composition of Ammi majus Seed Oil by Gas Chromatography Mass Spectrometry

The Ammi majus seeds oil constituents of methyl ester derivatives of fatty acids were analyzed using Gas Chromatography coupled to mass spectrometer. The results obtained containing the saturated as well as unsaturated fatty acids of majus seeds oils. A total of 18 different components were identified and quantified. Methyl ester of linoleic acid was found in high concentration 9.00%, among the identified analytes of interest. In addition methyl ester of Oleic acid 5.60%, Palmitic acid 3.98% Linolenic acids 1.42% were found. Concentration of the rest of identified fatty acids analytes were less than 1%. Thus from the results it is apparent that due to the presence of high percentage of valuable analytes concentrations detected in the fatty acid of A. majus, has increased its importance for the consumption in the pharmaceuticals as well as its applications in the new formulations for various skin diseases to prevent and cure from different infections.     

Fatty Acid Composition of Sideritis Species

Seed oils of 15Sideritisspecies collected from different regions in Turkey(S. athoa, S. brevidens, S. caesarea, S. condensata, S. congesta, S. dichotoma, S. erythrantha var. cedretorum, S. germanicopolitana ssp. germanicopolitana, S. hololeuca, S. lanata, S. libanotica ssp. violascens, S. lycia, S. niveotomentosa, S. perfoliata, S. phrygia, S. pisidica)were obtained by a Soxhlet apparatus using hexane. The oil yields were found to be between 5.6-36.3%. Fatty acids in the oils were converted to methyl esters and their compositions were determined by GC/MS. The main fatty acid components of the oils from all the species are linoleic (45.4-64.0%), oleic (12.3-26.5%), 6-octadecynoic (4.5-26.8%), palmitic (0.3-9.4%), and linolenic (0.8-2.0%) acids.