Journal articles: 'Fatty acids (Analysis; Determination)'

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Gabriel, Hancu, Tero-Vescan Amelia, Filip Cristina, and Rusu Aura. "Capillary Electrophoresis in the Analysis of Polyunsaturated Fatty Acids." Acta Medica Marisiensis 61, no. 4 (December 1, 2015): 378–81. http://dx.doi.org/10.1515/amma-2015-0103.

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AbstractThe aim of this study to inventory the main electrophoretic methods for identification and quantitative determination of fatty acids from different biological matrices. Critical analysis of electrophoretic methods reported in the literature show that the determination of polyunsaturated fatty acids can be made by: capillary zone electrophoresis, micellar electrokinetic chromatography and microemulsion electrokinetic chromatography using different detection systems such as ultraviolet diode array detection, laser induced fluorescence or mass – spectrometry. Capillary electrophoresis is a fast, low-cost technique used for polyunsaturated fatty acids analysis although their determination is mostly based on gas chromatography.

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Preet, Raman, and Raghbir Chand Gupta. "DETERMINATION OF FATTY ACIDS IN SOLANUM SURATTENSE BURM. F. BY USING GAS CHROMATOGRAPHY." Asian Journal of Pharmaceutical and Clinical Research 10, no. 8 (August 1, 2017): 60. http://dx.doi.org/10.22159/ajpcr.2017.v10i8.18314.

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Objective: This study aims to document the fatty acid composition of Solanum surattense Burm. f. collected from hot desert of India, Rajasthan.Methods: The fatty acid analysis was performed by gas chromatography-flame ionization detector (GC-FID). The operating conditions used to examine methyl esters of fatty acids are as follows. Fatty acids were converted into methyl esters (FAMEs) before GC analysis according to the standard methods by Ranganna (1986). Quantitative determinations of FAMEs were conducted using GC-FID and capillary column HP-88 Agilent Technologies.Results: The most abundant fatty was palmitic acid (13.2%), oleic acid (22.9%), and linoleic acid (11.9%). This plant is good source of important fatty acids including all the groups of saturated, monounsaturated, and polyunsaturated fatty acids (MUFAs and PUFAs) and can be used as a commercial source of fatty acids especially MUFAs and PUFAs.Conclusion: The plant is well studied for various pharmacological activities such as antiasthmatic, anticancer, cardiovascular, and hepatoprotective. Determination of fatty acid profiles in nutritional and clinical research with precision and fastness has become popular for human health and basic research.

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Pörschmann, S., J. Pörschmann, L. Liebetrau, I. Kühn, and R. Pätz. "Gas chromatographic analysis of free fatty acids. Part 2: Determination of free fatty acids during anaerobic putrefaction." Acta Biotechnologica 7, no. 5 (1987): 479–83. http://dx.doi.org/10.1002/abio.370070523.

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Savych, Alona, Svetlana Marchyshyn, and Roksolana Basaraba. "Determination of fatty acid composition content in the herbal antidiabetic collections." Pharmacia 67, no. 3 (September 14, 2020): 153–59. http://dx.doi.org/10.3897/pharmacia.67.e51812.

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It was determined the qualitative composition and the quantitative content of fatty acids in the herbal antidiabetic collection № 3, № 4, № 7, № 13, № 19, which are used in folk medicine for prevention and treatment of diabetes mellitus type 2 in Ukraine by GC/MS method. According to the results it was identified 8 fatty acids in the herbal antidiabetic collection № 3, 13 fatty acids in the herbal antidiabetic collection № 4, 12 fatty acids in the herbal antidiabetic collection № 7, 13 fatty acids in the herbal antidiabetic collection № 13 and 11 fatty acids in the herbal antidiabetic collection № 19. The saturated fatty acids were found to be dominated in the raw plant material. The results of the quantitative research showed that the herbal antidiabetic collection № 3 contains 16.13 mg/g of fatty acids, the herbal antidiabetic collection № 4 – 27.17 mg/g, the herbal antidiabetic collection № 7 – 31.98 mg/g, the herbal antidiabetic collection № 13 – 27.37 mg/g, the herbal antidiabetic collection № 19 – 18.79 mg/g. The GC/MS analysis of the fatty acid composition in the herbal antidiabetic collections has shown that this raw material has a lot of fatty acids, which can have a positive effect for the treatment and prevention of diabetes mellitus type 2.

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Müller, M., Š. Horníčková, P. Hrabě, and J. Mařík. "Analysis of physical, mechanical and chemical properties of seeds and kernels of Jatropha curcas ." Research in Agricultural Engineering 61, No. 3 (June 2, 2016): 99–105. http://dx.doi.org/10.17221/10/2014-rae.

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The research was performed to examine the physical, mechanical and chemical properties of seeds and kernels of Jatropha curcas. The test parameters were the dimensions of the seeds and kernels, required energy for oil extraction, determination of fatty acids in the oil by gas chromatography method, determination of the iodine value, determination of the acid value, determination of total polyphenols by the Folin & Ciocault reagent and determination of tocopherols and tocotrienols (vitamin E) by High-performance liquid chromatography. It was ascertained that the size of the seed and kernel varies considerably. Pressing of whole seeds needs more energy (50%) than pressing of kernels. From a chemical point of view it seems to be very appropriate for a production of biofuels. Jatropha curcas contains more polyphenols and vitamin E, which act as antioxidants, than the rape. Due to the low content of unsaturated fatty acids it is chemically suitable to replace the rape-seed oil with Jatropha curcas oil.

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Belichovska, Daniela, Zehra Hajrulai-Musliu, Risto Uzunov, Katerina Belichovska, and Mila Arapcheska. "Fatty Acid Composition of Ostrich (Struthio Camelus) Abdominal Adipose Tissue." Macedonian Veterinary Review 38, no. 1 (March 1, 2015): 53–59. http://dx.doi.org/10.14432/j.macvetrev.2014.11.028.

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Abstract Fatty acid composition of foods has a great impact on nutrition and health. Therefore, thе determination and knowledge of the fatty acid composition of food is very important for nutrition. Due to the high nutritional characteristics of ostrich meat and its products, the research determining their quality is of topical interest. The aim of the present investigation was the determination of fatty acid composition of ostrich adipose tissue. The content of fatty acids was determined according to AOAC Official Methods of Analysis and determination was performed using a gas chromatograph with a flame-ionization detector (GC-FID). The results are expressed as a percentage of the total content of fatty acids. The method was validated and whereupon the following parameters were determined: linearity, precision, recovery, limit of detection and limit of quantification. The repeatability was within of 0.99 to 2.15%, reproducibility from 2.01 to 4.57%, while recovery ranged from 94.89 to 101.03%. According to these results, this method is accurate and precise and can be used for analysis of fatty acids in foods. It was concluded that the content of saturated fatty acids (SFA) accounted 34.75%, of monounsaturated fatty acids (MUFA) 38.37%, of polyunsaturated fatty acids (PUFA) 26.88%, of total unsaturated fatty acids (UFA) 65.25% and of desirable fatty acids (DFA) (total unsaturated + stearic acid) 70.37% of the analysed samples. The ratio polyunsaturated/saturated fatty acids accounted 0.77. The most present fatty acid is the oleic (C18:1n9c) with 28.31%, followed by palmitic (C16:0) with 27.12% and linoleic (C18:2n6c) acid with 25.08%. Other fatty acids are contained in significantly lower quantities.

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Nishiyama-Naruke, A., J. A. Souza, M. Carnelós, and R. Curi. "HPLC Determination of Underivatized Fatty Acids Saponified at 37°C Analysis of Fatty Acids in Oils and Tissues." Analytical Letters 31, no. 14 (November 1998): 2565–76. http://dx.doi.org/10.1080/00032719808005325.

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Taufik, Moh, Hanifah Nuryani Lioe, and Nancy Dewi Yuliana. "Evaluation of Major Fatty Acids Determination in Palm Oil by Gas Chromatography-Flame Ionization Detection." Jurnal Agritech 36, no. 03 (December 21, 2016): 308. http://dx.doi.org/10.22146/agritech.16603.

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The fatty acid composition of palm oil is the major factor influencing its physical and chemical properties. The purpose of this research was to evaluate the analytical performance of major fatty acids (palmitic acid, stearic acid, oleic acid, and linoleic acid) analysis in palm oil. Triglycerides of palm oil were derivatized to fatty acid methyl esters (FAMEs) by using boron trifluoride (BF3) in methanol. FAMEs were determined by gas chromatography-flame ionization detection (GC-FID) using DB-23 capillary column as stationary phase. The studied parameters were instrument performance analysis, the efficiency of fatty acid derivatization, stability of derivatized analytes, accuracy, repeatability, intra-lab reproducibility, ruggedness, and method uncertainty. The evaluation results showed the instrument linearity at a working range of 5 to 40 mg/mL marked by coefficient of determination (R2) between 0.991-0.995. Instrument limits of detection (LOD) and instrument limits of quantification (LOQ) for 4 major fatty acids analysis were 26-35 µg/mLand 86-128 µg/mL, respectively. The increase of fatty acid concentration led to the decrease of derivatization efficiency in the fatty acids analysis. The result also showed that derivatized analytes were stable during 24 h storage at freeze temperature. The average recovery values by spiking method with the spiking concentration at 50 and 90 mg/g sample were at 75-94 % for stearic and linoleic acids analysis, however those for palmitic and oleic acids analysis were considered very low (<40 %), due to their low derivatization efficiency. Repeatability and intra-lab reproducibility of 4 major fatty acids analysis were at acceptable ranges, 0.45-1.38 % and 1.15-2.03 %, respectively. Determination by varying the volume of derivatizing agent showed the rugged method. Uncertainty of repeatability (Ur) and uncertainty of reproducibility (Ur) were ranged at 1.84-9.02 mg/g and 1.40-10.65 mg/g, respectively. This method was considerably reliable for the analysis of less abundance fatty acids in palm oil, stearic and linoleic acids.

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Jensen, Nancy J., and Michael L. Gross. "Mass spectrometry methods for structural determination and analysis of fatty acids." Mass Spectrometry Reviews 6, no. 4 (1987): 497–536. http://dx.doi.org/10.1002/mas.1280060403.

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Zeile, W. L., D. A. Knauft, and C. B. Kelly. "A Rapid Non-Destructive Technique for Fatty Acid Determination in Individual Peanut Seed1." Peanut Science 20, no. 1 (January 1, 1993): 9–11. http://dx.doi.org/10.3146/i0095-3679-20-1-3.

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Abstract Modification of fatty acid composition can improve the keeping quality of peanut oil and may expand markets for peanut usage. Modification may involve hybridization to recombine existing genes, or the creation of new variability through mutagenesis or transformation with genes from other organisms. Identification of the fatty acid composition of individual seed could improve the chances of obtaining peanut genotypes with desired fatty acid composition. Published techniques for fatty acid analysis of individual peanut seed require the use of approximately half the cotyledonary seed tissue and utilize a process of solvent extraction and esterification. We have used a procedure that requires a small fraction of seed tissue and analyzes fatty acids through direct transmethylation. Comparisons were made between procedures using seven genotypes representing a wide range of fatty acid composition variability. Quantities of fatty acids with C<20 were not statistically different between tests. While some differences were observed in longer-chained fatty acids (C≥20), the relative values among genotypes were similar. This procedure maintains greater integrity of the seed for planting purposes, requires less time and cost for fatty acid analysis, and can improve efficiency of individual seed analysis.

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Agradi, Stella, Giulio Curone, Daniele Negroni, Daniele Vigo, Gabriele Brecchia, Valerio Bronzo, Sara Panseri, et al. "Determination of Fatty Acids Profile in Original Brown Cows Dairy Products and Relationship with Alpine Pasture Farming System." Animals 10, no. 7 (July 20, 2020): 1231. http://dx.doi.org/10.3390/ani10071231.

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This study aimed to evaluate the relationships between fatty acids and the pattern that most contributes to discriminate between two farming systems, in which the main difference was the practice, or not, of alpine summer-grazing. Milk and cheese were sampled every month in two farms of Original Brown cows identical under geographical location and management during no grazing season point of view in the 2018 season. Fatty acids concentrations were determined by gas chromatography. The principal component analysis extracted three components (PCs). Mammary gland de novo synthetized fatty acids (C14:0, C14:1 n9, and C16:0) and saturated and monosaturated C18 fatty acids (C18:0, C18:1 n9c) were inversely associated in the PC1; PC2 included polyunsaturated C18 fatty acids (C18:2 n6c, C18:3 n3) and C15:0 while conjugated linoleic acid (CLA n9c, n11t) and fatty acids containing 20 or more carbon atoms (C21:0, C20:5 n3) were associated in the PC3. The processes of rumen fermentation and de novo synthesis in mammary gland that are, in turn, influenced by diet, could explain the relationships between fatty acids within each PC. The discriminant analyses showed that the PC2 included the fatty acids profile that best discriminated between the two farming systems, followed by PC3 and, lastly, PC1. This model, if validated, could be an important tool to the dairy industry.

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Lolli, Veronica, Angela Marseglia, Gerardo Palla, Emanuela Zanardi, and Augusta Caligiani. "Determination of Cyclopropane Fatty Acids in Food of Animal Origin by 1H NMR." Journal of Analytical Methods in Chemistry 2018 (2018): 1–8. http://dx.doi.org/10.1155/2018/8034042.

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Cyclopropane fatty acids (CPFAs) are unusual fatty acids of microbial origin, recently detected in milk and dairy products. CPFAs have been demonstrated to be interesting molecular markers for authentication of dairy products obtained without ensiled feeds. Moreover, they can also be recognized as a new secondary component of human diet. Information is lacking on the presence of cyclic fatty acids in other food sources. Cyclopropane fatty acids have been detected by GC-MS analysis in cheese and other animal fats in concentration ranging from 200 to 1000 mg/kg fat, but in some cases, the complex fatty acid profile and the possible presence of interfering peaks make the separation not straightforward and the quantification uneasy. Therefore, a new reliable 1H NMR method was developed to detect and measure CPFA content in different foods of animal origin, based on the detection of the characteristic signals of cyclopropane ring. The 1H NMR (600 MHz) method showed detection limits comparable with those of full scan GC-MS, and it allowed the identification and quantitation of the cyclopropane fatty acids in different foods.

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Püttmann, M., H. Krug, E. von Ochsenstein, and R. Kattermann. "Fast HPLC determination of serum free fatty acids in the picomole range." Clinical Chemistry 39, no. 5 (May 1, 1993): 825–32. http://dx.doi.org/10.1093/clinchem/39.5.825.

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Abstract We developed a method for determining individual free fatty acids in serum by using a modified one-step Dole extraction, derivatization, and a new high-performance liquid chromatographic (HPLC) separation. Sample handling is minimized to a single transfer of the fatty acids (upper layer of the Dole extract), which are readily derivatized at 85 degrees C with p-bromophenacyl bromide without significant hydrolysis of esterified fatty acids. The derivatization mixture is directly injected into the HPLC apparatus. The new method, which uses C6 (3-microns particle) column material and an isocratic acetonitrile-water eluent, separates nearly to baseline 12 of the physiologically most abundant long-chain fatty acids (C12-C22) in < 20 min with a detection limit of approximately 2 pmol. It is therefore suitable for routine analysis even with basic HPLC equipment and can easily analyze a series of 10-20 samples in about 2 h including extraction until first results are available. The method is also applicable to other matrices than serum, e.g., for determination of precursor fatty acids such as arachidonic acid in platelets or of fatty acid patterns liberated by lipases or phospholipases A1/A2 in test systems.

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Pietrzak-Fiećko, R., R. Tomczyński, and S. S. Smoczyński. "Effect of lactation period on the fatty acid composition in mares’ milk from different breeds." Archives Animal Breeding 56, no. 1 (October 10, 2013): 335–43. http://dx.doi.org/10.7482/0003-9438-56-033.

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Abstract. Analyses were carried out on the fatty acid composition of milk fat originating from mares of three breeds: Polish Cold-Blooded, Wielkopolski and Konik Polski. Milk was collected from mares in the early, mid and late lactation. Determination of fatty acids was conducted with the gas chromatography method. The analysis of the fatty acid composition demonstrated that over the entire lactation period unsaturated fatty acids (from 52.96 % to 62.46 %), represented mainly by linolenic (22.15 %) and oleic (19.98 %) acid, were predominantly present only in samples originating from mares of the Wielkopolski breed. In milk of mares of Konik Polski, saturated fatty acids appeared to predominate (51.95 % and 52.95 %) in the early and mid lactation, whereas unsaturated fatty acids (62.28 %) predominated in the late lactation. In the case of milk samples of the Polish Cold-Blooded mares, saturated fatty acids (represented mainly by palmitic acid) were observed to prevail in the early and late lactation (55.77 % and 61.31 %), whereas unsaturated fatty acids (52.20 %) were found to negligibly prevail in the mid lactation. The study confirmed that fatty acid composition was determined by the period of lactation and breed of the mares.

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DECALLONNE, J., M. DELMEE, P. WAUTHOZ, M. EL LIOUI, and R. LAMBERT. "A Rapid Procedure for the Identification of Lactic Acid Bacteria Based on the Gas Chromatographic Analysis of the Cellular Fatty Acids." Journal of Food Protection 54, no. 3 (March 1, 1991): 217–24. http://dx.doi.org/10.4315/0362-028x-54.3.217.

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This study was conducted to develop a rapid numerical procedure for the analysis of gas chromatograms of lactic acid bacteria fatty acid methylesters (FAMEs), along with an examination of some experimental conditions which affect the fatty acid composition of these bacteria. FAME determination was carried out using high resolution gas chromatography (HRGC). Although the nature and the proportion of fatty acids differed among strains, some major components, n-C14:0, n-C16:1, n-C16:0, n-C18:1, n-C18:0, and C19 cycl, were found as a group to represent more than 90% of the whole cellular fatty acids. The differences found in the relative composition of the long-chain fatty acids in paired chromatograms were used to calculate a “distance coefficient”, based on the differences found for the most important fatty acids, after their prior ranking. The procedure was initially validated with identified species, used as reference strains; then, unknown lactic acid bacteria isolates were compared to these references. The method proved to be useful for rapid comparisons between strains, provided a strict standardization occcurred prior to routine application.

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Miwa, Hiroshi, and Magobei Yamamoto. "Rapid Liquid Chromatographic Determination of Fatty Acids as 2-Nitrophenylhydrazine Derivatives." Journal of AOAC INTERNATIONAL 79, no. 2 (March 1, 1996): 493–97. http://dx.doi.org/10.1093/jaoac/79.2.493.

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Abstract Direct derivatization of saponified fats and oils with 2-nitrophenylhydrazine hydrochloride produced corresponding fatty acid hydrazides without timeconsuming sample cleanup and/or extraction steps. Hydrazides were injected directly into a liquid chromatograph. Improved isocratic separation was achieved within only 22 min for 29 saturated and mono- and polyunsaturated fatty acids (C8:0- C22:6), including cis-trans isomers and doublebond positional isomers. The technique has good quantitative accuracy while reducing analysis time, cost, and labor.

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Butler, Gillian, and Sokratis Stergiadis. "Suitability of bronopol preservative treated milk for fatty acid determination." Journal of Dairy Research 78, no. 2 (March 17, 2011): 220–25. http://dx.doi.org/10.1017/s0022029911000082.

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This work aimed to test if milk preserved with bronopol can be reliably used for fatty acid determination. Dairy production and milk quality are often monitored regularly to assess performance and contribute to selection indices. With evidence that fat composition can be influenced by selective breeding, there might be an interest in using samples collected in routine testing to evaluate individual cow fatty acid profiles, contributing to breeding indices. However, most recording services use a preservative such as bronopol and there is no published record if this influences subsequent fatty acid analysis. This study used milk from an oil seed supplementation trial, generating a wide range of milk fatty acid profiles, to test if the concentration of 31 individual fatty acids determined by GC were influenced by bronopol. Provided preserved samples are subsequently frozen, milk treated with bronopol can reliably be used to evaluate fatty acid composition in most cases; however bronopol might influence a few long-chain fatty acids present in relatively low concentrations. This is one small step towards simplifying milk compositional analysis but it could ultimately streamline the inclusion of milk fat quality into breeding indices, either with a view to ‘healthier’ milk or potentially reducing methane output and the environmental impact of dairy production.

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Attaelmannan, M. A., A. A. Dahl, and R. S. Reid. "Analysis of volatile fatty acids in rumen fluid by proton NMR spectroscopy." Canadian Journal of Animal Science 79, no. 3 (September 1, 1999): 401–4. http://dx.doi.org/10.4141/a99-013.

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A study was conducted to quantify the volatile fatty acid (VFA) concentrations in aqueous and rumen fluid samples using a standard additions based quantitative proton nuclear magnetic resonance (NMR) spectroscopic method. Standard plots for acetic, propionic and butyric acids were all found to be linear (R2 > 0.99). Results obtained by NMR were compared with those obtained using the conventional gas chromatographic method. No significant differences were found between the means and precisions of the two techniques (P < 0.05). The method is well-suited for the routine quantification of these acids, requires no sample pretreatment and is more rapid than gas chromatography. Key words: Volatile fatty acid determination, rumen fluid, gas chromatography, nuclear magnetic resonance spectroscopy

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Cantellops, Dennis, Anne P. Reid, Ronald R. Eitenmiller, and Austin R. Long. "Determination of Lipids in Infant Formula Powder by Direct Extraction Methylation of Lipids and Fatty Acid Methyl Esters (FAME) Analysis by Gas Chromatography." Journal of AOAC INTERNATIONAL 82, no. 5 (September 1, 1999): 1128–39. http://dx.doi.org/10.1093/jaoac/82.5.1128.

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Abstract Fatty acid methyl esters (FAMEs) of pure triglyceride standards, oils, and fat from dry matrixes were formed by transesterification using sodium methoxide in methanol–hexane. FAMEs were produced by direct addition of sodium methoxide¯hexane to samples and heating to simultaneously extract and transesterify acyl lipids. FAMEs were quantitated by capillary gas chromatography (GC) over a fatty acid concentration range of 0 to 1.7 mg/mL (r ≥ 0.9997). Total fat was calculated as the sum of individual fatty acids expressed as triglyceride equivalents, in accordance with nutrition labeling guidelines. Saturated, polyunsaturated, and monounsaturated fats were calculated as sums of individual free fatty acids. Absolute recoveries determined from individual fatty acids in test samples ranged from 69.7 to 106%. Recoveries (relative to the C13:0 internal standard) for individual fatty acids in test samples ranged from 95 to 106%. Reproducibility was constant at each fatty acid level in the reaction mixture (n = 5, coefficient of variation [CV] <2%). Absolute recovery determined from the sum of total fatty acids in standard reference material (SRM) 1846 (powdered infant formula) was 96.4%. Analysis of SRM 1846 gave results that agreed closely with the certified fat and fatty acid values. Analysis of commercial infant formula gave results that were comparable to those obtained with AOAC Method 996.01. The direct extraction methylation procedure is rapid, and the transesterification of acyl lipids to form FAMEs is complete within 15 min. Classical saponification and refluxing are not required. This method provides FAMEs free of interferences and easily quantitated by GC or confirmed by GC/mass spectrometry (MS). Unambiguous MS identification of individual FAMEs derived from pure standards, SRM 1846, and powdered infant formula product was obtained.

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Qadir, Abdul, Athar Ali, Muhammad Arif, Abdulmohsen Al-Rohaimi, Satya Singh, Usama Ahmad, Mohd Khalid, and Arun Kumar. "Solvent Extraction and GC-MS Analysis of Sesame Seeds for Determination of Bioactive Antioxidant Fatty Acid/Fatty Oil Components." Drug Research 68, no. 06 (December 12, 2017): 344–48. http://dx.doi.org/10.1055/s-0043-123466.

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AbstractThe seed kernels of Sesamum indicum L. (family: Pedaliaceae) were extracted with ethanol and yield of components determined by Gas Chromatography/Mass Spectrometry (GC/MS). The free radical scavenging activities of ethanolic extract against1, 1-Diphenyl-2-picrylhydrazyl (DPPH) were determined by UV spectrophotometer at 517 nm. Phytochemical screening revealed the presence of numerous bioactive compounds including steroids, phenolic, terpenoids, fatty acids and different types of ester compounds. The ethanolic extract was purified and analyzed by GC MS.The prevailing compounds found in ethanolic extract were Carvacrol (0.04%),Sesamol (0.11%), 4-Allyl-2-methoxy-phenol(0.04%),Palmitic acid (1.08%), cis-9-Hexadecenal (85.40%), Lineoleoyl chloride (0.52%), Palmitic acid β-monoglyceride (0.40%), Dihydro-aplotaxene (0.61%), Oleoyl chloride (1.11%), (+)-Sesamin (4.73%), 1,3-Benzodioxole, 5-[4-(1,3-benzodioxol-5-yloxy)tetrahydro-1 H,3 H-furo [3,4-c]furan-1-yl], [1 S-(1,3,4,6α.), (2.01%)], 6-Nitrocholest-5-en-3-yl acetate (0.22%), Ergost-5-en-3β-ol (2.35%) and 24-Propylidenecholesterol (0.16%). The presence ofsaturated and unsaturated fatty acids in ethanolicextract justifies the use of this plant to treat many ailments in folk and traditional medicine. Ethanolic extract have shown significant antioxidant activity(IC50120.38±2.8 µg/ml). The presence of phenolic (Sesamol), lignin (Sesamin) compounds and unsaturated fatty acids are reported as possible contributor for antioxidantactivity of seed extract.

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Menéndez, Luis García, Ana L. Fernández, Alfredo Enguix, Constanza Ciriza, and Juan Amador. "Effect of storage of plasma and serum on enzymatic determination of non-esterified fatty acids." Annals of Clinical Biochemistry: International Journal of Laboratory Medicine 38, no. 3 (May 1, 2001): 252–55. http://dx.doi.org/10.1258/0004563011900470.

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Many contradictory results have been published on the stability of total non-esterified fatty acids in blood, plasma and serum under different storage conditions. The present study was undertaken to investigate the stability of non-esterified fatty acids, measured with an enzymatic method, in samples of EDTA-treated plasma and serum under different temperature conditions. We conclude that EDTA-treated plasma and serum can both be used for analysis. Specific reference values should be established depending on the type of sample chosen. Samples that cannot be analysed immediately can be stored at -20°C for at least 14 days without significant changes in the concentration of total non-esterified fatty acids. None of the other storage conditions and periods studied are suitable for the measurement of non-esterified fatty acid concentration.

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Ratnayake, W. M. N., J. Conway, and R. G. Ackman. "Determination of Cyclopropenoic Fatty Acids in Oils by Hydrazine Reduction Followed Glc Analysis." Canadian Institute of Food Science and Technology Journal 18, no. 3 (September 1985): xxxix. http://dx.doi.org/10.1016/s0315-5463(85)71865-2.

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Bahadori, Mir Babak, Solmaz Asnaashari, and Hossein Nazemiyeh. "Fatty Acid Profile of Roots and Aerial Parts of Ruscus hyrcanus Woronow." Pharmaceutical Sciences 25, no. 1 (March 18, 2019): 78–81. http://dx.doi.org/10.15171/ps.2019.12.

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Background: Ruscus specie are used as traditional medicine, food, and foliage. The aim of this work is the determination of fatty acid composition of Ruscus hyrcanus as a native medicinal plant of Iran for the first time together with comparison of different esterification methods. Methods: Two different esterification methods were used for preparation of esterified fatty acids from different extracts of underground and aerial parts of the herb. GC/MS analysis were used for identification and quantification of fatty acids. Finally, the results were compared. Results: Findings showed that R. hyrcanus is rich in essential fatty acids such as linoleic acid (13-25%) and linolenic acid (23-44%). Also, oil samples contain remarkable amount of palmitic acid (19-57%). Conclusion: The results showed that R. hyrcanus could be considered as a source of essential fatty acids. Also, it could be concluded that a simple esterification method with methanolic KOH and 2 min vortex is suitable for fatty acid analysis of Ruscus species.

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Sundaram, Jaya, Chari V. Kandala, Christopher L. Butts, Charles Y. Chen, and Victor Sobolev. "Nondestructive NIR Reflectance Spectroscopic Method for Rapid Fatty Acid Analysis of Peanut Seeds." Peanut Science 38, no. 2 (July 1, 2011): 85–92. http://dx.doi.org/10.3146/ps10-3.1.

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ABSTRACT Near Infrared Reflectance Spectroscopy (NIRS) was used to rapidly and nondestructively analyze the fatty acid concentration present in peanut seeds samples. Absorbance spectra were collected in the wavelength range from 400 nm to 2500 nm using NIRS. The oleic, linoleic and palmitic fatty acids were converted to their corresponding methyl esters and their concentrations were measured using a gas chromatograph (GC). Partial least square (PLS) analysis was performed on a calibration set, and models were developed for prediction of fatty acid concentrations. The best model was selected based on the coefficient of determination (R2), Root Mean Square Error of Prediction, residual percent deviation (RPD) and correlation coefficient percentage between the gas chromatography measured values and the NIR predicted values. The NIR reflectance model developed yielded RPD values of three and above for prediction of the three fatty acids, indicating that this nondestructive method would be suitable for fatty acid predictions in peanut seeds.

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Ming, Lang, Zhe Chen, Jun Zhang, Fu Rong Huang, Meng Yuan Xie, Yong Wang, and Er Pei Wang. "The Detection of Glycerate and Free Fatty Acids by the Method of Near-Infrared Spectroscopy." Applied Mechanics and Materials 333-335 (July 2013): 1586–90. http://dx.doi.org/10.4028/www.scientific.net/amm.333-335.1586.

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The monoglyceride, diglyceride, triglyceride and free fatty acids in vegetable oil was detected by the analysis method of near-infrared spectroscopy. The near-infrared spectrograms of 77 oil samples were collected, including 67 samples for calibration set and 10 samples for prediction set. The Partial Least Squares (PLS) optimized models were established with OPUS chemical analysis software. The results demonstrated that the determination coefficient of monoglyceride, diglyceride, triglyceride and free fatty acids was 0.9691,0.8627,0.8742 and 0.9194, respectively. And the standard error of prediction for the four components was 0.0104, 0.1830.201 and 0.0106, respectively. The presented results showed that the analysis method of near-infrared spectroscopy can be used to identify the diglycerides and triglycerides, but as for monoglyceride and free fatty acids, further experimental verification is needed.

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Liu, Liyan, Ying Li, Rennan Feng, and Changhao Sun. "Direct ultrasound-assisted methylation of fatty acids in serum for free fatty acid determinations." Canadian Journal of Chemistry 88, no. 9 (September 2010): 898–905. http://dx.doi.org/10.1139/v10-077.

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A method for simultaneous determination of 16 free fatty acids (FFAs) in serum is described. The method involves conversion of FFAs to fatty acid methyl esters (FAMEs) using the heat of ultrasonic waves followed by gas chromatography and mass spectrometry (GC–MS) analysis. Optimum levels of the variables affecting the yield of FAMEs were investigated. The results indicate that the optimal levels are 55 °C, 60 W, 10% H2SO4/CH3OH, and 50 min. Recoveries ranged from 85.32% to 112.11%, with a detection limit ranging from 0.03 to 0.08 μg mL–1. The linearity, using the linear correlation coefficient, was higher than 0.9914.

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Dhalani, Jayesh, Gaurang Dubal, Chirag Rathod, and Pankaj Nariya. "Evaluation of Non-polar Composition in Plumbago Zeylanica Leaves by Gas Chromatography and Mass Spectrometry." Folia Medica 62, no. 2 (June 30, 2020): 308–13. http://dx.doi.org/10.3897/folmed.62.e47647.

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Background:Plumbago zeylanica plant belongs to Plumbaginaceae. The plant is reported for many pharmacological activities. Aim: The objective of the study was to identify fatty acids and non-polar chemical compounds in Plumbago zeylanica leaves. Materials and methods: Petroleum ether extract was prepared using soxhlet apparatus. Saponifiable and unsaponifiable matter was separated with saponification process. To identify fatty acids in saponifiable matter further esterification was performed. Gas chromatography and mass spectrometry analysis was performed of both saponifiable and unsaponifiable fractions. All the fatty acid methyl esters and non-polar chemical compounds were identified using NIST library data. Results: A total of 14 compounds were identified with comparison of NIST data. From that, 8 fatty acid methyl esters and 6 non-polar chemical compounds were identified. Here we have analyzed fatty acids and non-polar chemical compounds by the same GC-MS method. Conclusions: The present analysis showed that Plumbago Zeylanica leaves contain 8 fatty acids and 6 non-polar chemical compounds. Principal determination of the research was development of efficient method to identify non-polar compound from plant by single injection using chromatographic technique.

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Gliszczyńska-Świgło, Anna, Żaneta Jajor, and Dominik Kmiecik. "Fourier-transform near infrared spectroscopy and chemometrics for discrimination of cold-pressed oils and determination of their chemical parameters." Journal of Near Infrared Spectroscopy 26, no. 4 (August 2018): 262–72. http://dx.doi.org/10.1177/0967033518796701.

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Principal component analysis was performed to discriminate commercial cold-pressed cosmetic oils based on their Fourier-transform near infrared spectroscopy spectra and chemical parameters such as the composition of fatty acids, content of tocopherols, total carotenoids, polyphenols, and chlorophylls, as well as calculated oxidizability and iodine values. It was found that the oils analyzed differed significantly in the chemical composition. The level of total unsaturated fatty acids ranged from 74.0 to 93.4%. The content of carotenoids in oils ranged from 3.1 to 197.1 mg/kg, total chlorophylls from 0.04 to 46.3 mg/kg, and total phenolics from 36 to 596 mg/kg. The oils tested differed also in the content of tocopherols (from 11 to 3836 mg/kg). Principal component analysis based on Fourier-transform near infrared spectroscopy spectra revealed a different pattern of discrimination of the oils compared to principal component analysis based on the chemical parameters. However, using partial least squares regression, good correlations were found between Fourier-transform near infrared spectroscopy spectra and the contribution of linoleic acid (18:2), monounsaturated fatty acids, polyunsaturated fatty acids, unsaturated fatty acids, calculated oxidizability, or calculated iodine values. Good models with coefficients of determination not lower than 0.989 and with low root-mean-square error for cross-validation were obtained when the range from 4800 to 4500 cm−1 was applied. Values of residual predictive deviation for these models were higher than 3.0 indicating very good prediction accuracy. The models obtained were successfully used to predict these parameters for new selected oils.

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Su, Ning, Fangfang Pan, Liusan Wang, and Shizhuang Weng. "Rapid Detection of Fatty Acids in Edible Oils Using Vis-NIR Reflectance Spectroscopy with Multivariate Methods." Biosensors 11, no. 8 (August 3, 2021): 261. http://dx.doi.org/10.3390/bios11080261.

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The composition and content of fatty acids are critical indicators to identify the quality of edible oils. This study was undertaken to establish a rapid determination method for quality detection of edible oils based on quantitative analysis of palmitic acid, stearic acid, arachidic acid, and behenic acid. Seven kinds of oils were measured to obtain Vis-NIR spectra. Multivariate methods combined with pretreatment methods were adopted to establish quantitative analysis models for the four fatty acids. The model of support vector machine (SVM) with standard normal variate (SNV) pretreatment showed the best predictive performance for the four fatty acids. For the palmitic acid, the determination coefficient of prediction (RP2) was 0.9504 and the root mean square error of prediction (RMSEP) was 0.8181. For the stearic acid, RP2 and RMSEP were 0.9636 and 0.2965. In the prediction of arachidic acid, RP2 and RMSEP were 0.9576 and 0.0577. In the prediction of behenic acid, the RP2 and RMSEP were 0.9521 and 0.1486. Furthermore, the effective wavelengths selected by successive projections algorithm (SPA) were useful for establishing simplified prediction models. The results demonstrate that Vis-NIR spectroscopy combined with multivariate methods can provide a rapid and accurate approach for fatty acids detection of edible oils.

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Pinkevych, Viktoriia O., Moeen F. Dababneh, Nadiia Ye Burda, and Iryna O. Zhuravel. "Fatty acid composition of night-scented stock (Matthiola bicornis (Sibth. & Sm.) DC.) raw materials." Current Issues in Pharmacy and Medical Sciences 34, no. 1 (March 1, 2021): 34–41. http://dx.doi.org/10.2478/cipms-2021-0007.

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Abstract Introduction. With due consideration of the properties of fatty acids, as well as their importance for normal life activity and human development, research into the fatty acid composition of poorly studied plants and the search for new domestic plant sources of polyunsaturated fatty acids is a mainstream trend in modern pharmacy. Aim. Aim of research – determination of fatty acid qualitative composition and content in threshed grass, stalks, roots and seeds of Night-scented stock ‘Queen of Night’ and ‘Evening Scent’ cultivars as grown in Ukraine. Methods. Gas chromatography. Results. Both cultivars of Night-scented stock taken for analysis had similar fatty acid composition – 5 saturated, 5 (4 for seeds) monounsaturated and 2 polyunsaturated fatty acids, Quantitatively, in all tested parts of the herb polyunsaturated and monounsaturated fatty acid dominated, making in total 88.92% and 88.62% in the seeds of Queen of Night and Evening Scent cultivars, respectively, and averaging 65% in other parts of the tested cultivars. Linolenic and linoleic acids prevailed among the polyunsaturated fatty acids, whereas oleic acid prevailed among the monounsaturated. Conclusion. Night-scented stock can be utilized as a source of polyunsaturated fatty acids for the development of drugs and for standardization of tested raw materials.

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Štěrba, Karel, Pavel Čejka, and Jana Olšovská. "Influence of beer and wort sample freezing on the result of analysis." KVASNY PRUMYSL 66, no. 4 (July 31, 2020): 307–13. http://dx.doi.org/10.18832/kp2019.66.307.

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Freezing is a common way of storing samples including beer samples. To verify the suitability of this procedure, the results of determination of alcohol (% v/v), original gravity, color, pH, thiobarbituric acid index, total polyphenols, saccharides, limit of attenuation, free amino nitrogen, protein nitrogen by coomassie brilliant blue, iso-α-bitter acids, diacetyl, higher alcohols, esters, fatty acids, carbonyl compounds and hop oils in beer, and protein nitrogen by coomassie brilliant blue and total polyphenols in wort were compared before and after freezing the sample. It was found that most determinations were not affected by sample freezing, but the determinations of alcohol, original gravity and total polyphenols were affected. In case these very frequent determinations would need to be performed after freezing, a new uncertainty of the method was calculated for these analyzes. From the spectrum of fifteen tested carbonyl compounds, there was a statistically significant increase in the concentration of four compounds (2-methylpropanal, 2-methylbutanal, 3-methylbutanal, phenylacetaldehyde). A significant decrease after sample freezing was observed for most of the analyzed essential oils.

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Conte, L. S., O. Leoni, S. Palmieri, P. Capella, and G. Lercker. "Half-Seed Analysis: Rapid Chromatographic Determination of the Main Fatty Acids of Sunflower Seed*." Plant Breeding 102, no. 2 (March 1989): 158–65. http://dx.doi.org/10.1111/j.1439-0523.1989.tb00330.x.

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Mitchell, Barb, Brent Rozema, Thomas Vennard, and Jane Sabbatini. "Determination of Nutritional and Cyclopropenoid Fatty Acids in Cottonseed by a Single GC Analysis." Journal of the American Oil Chemists' Society 92, no. 7 (June 21, 2015): 947–56. http://dx.doi.org/10.1007/s11746-015-2669-5.

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Jarukas, Laurynas, Greta Kuraite, Juste Baranauskaite, Mindaugas Marksa, Ivan Bezruk, and Liudas Ivanauskas. "Optimization and Validation of the GC/FID Method for the Quantification of Fatty Acids in Bee Products." Applied Sciences 11, no. 1 (December 24, 2020): 83. http://dx.doi.org/10.3390/app11010083.

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To the best of our knowledge, so far, no study has been conducted about the comparison of the total fatty acid concentration in the four bee products (honey, bee pollen, bee bread, and propolis) collected from Lithuania. Therefore, we aimed to optimize the derivatization parameters and to investigate a simple and sensitive gas chromatography-flame ionization detection (GC-FID) method to determine fatty acids. The optimal derivatization parameters were used to analyze fatty acids in the bee products. Regarding sample preparation, three derivatization parameters were compared (temperature and extraction time with BF3/MeOH reagent) in order to obtain a high amount of the total fatty acids of interest from the fatty acid methyl ester (FAME) standard. The results showed that the highest total yield of fatty acids was conducted by using the conventional heating process at 70 °C for 90 min. Under optimal conditions, there was obtained excellent linearity for fatty acids with determination coefficients of r2 > 0.9998. The LODs and LOQs ranged from 0.21 to 0.54 µg/mL and 0.63 to 1.63 µg/mL, respectively. This method has been successfully applied to the qualitative analysis of fatty acids in bee products. The above findings might provide a scientific basis for evaluating the nutritional values of bee products.

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35

Lee, M. J., T. Crook, C. Noel, and U. M. Levinson. "Detergent extraction and enzymatic analysis for fecal long-chain fatty acids, triglycerides, and cholesterol." Clinical Chemistry 40, no. 12 (December 1, 1994): 2230–34. http://dx.doi.org/10.1093/clinchem/40.12.2230.

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Abstract We report a procedure for determining fecal long-chain fatty acids (LCFA), triglycerides, and cholesterol after detergent extraction with 10 mL/L Triton X-100, 6 mL/L Brij 30, and 0.1 mol/L HCl in isotonic saline by enzymatic analysis of the extraction supernates. Mean recoveries of calibrators ranged from 105% to 117%. Assays of fecal extracts were linear with concentration from 0 to 1000 mumol/L for LCFA, from 10 to 90 mumol/L for triglycerides, and from 0 to 300 mumol/L for cholesterol. Within-run CVs were < 3% for medium and high concentrations, and 3%, 14%, and 28% for low concentrations of LCFA, cholesterol, and triglycerides, respectively. Correlation with gravimetric determination resulted in coefficients (r2) of 0.72 for total fat, 0.63 for neutral fat, and 0.66 for nonesterified fat. Assays of extracts and residues prepared for gravimetric determination indicated that approximately 90% of triglycerides, cholesterol, and LCFA were extracted by organic solvents and that the extracts contain a significant amount of other fats. The proposed method appears accurate, precise, specific, and suitable for routine analysis.

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36

Akinyemi, Olufunmilola, Geza Bruckner, John Johnson, Terry A. Lennie, and David Hildebrand. "A Rapid and Simple Method for Fatty Acid Profiling and Determination of ω-3 Index in Red Blood Cells." Open Nutrition Journal 11, no. 1 (January 31, 2017): 17–26. http://dx.doi.org/10.2174/1874288201711010017.

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Fatty acid profiling has become a very useful and effective tool in the diagnosis, prevention and treatment of several diseases with cardiovascular disease being particularly important. In order to arrive at accurate conclusions that would help promote the health of individuals plagued by such diseases, not only excellent laboratory methods are required, but also very important monitoring responses to treatment. Improvements in methods of fatty acid profiling in biological systems regarding safety of extraction, precision and time for analysis are valuable. The ω-3 index (a measure of the amount of eicosapentaenoic acid, EPA, and docosahexaenoic acid, DHA, in Red Blood Cell membranes expressed as the percent of total fatty acids) is of growing interest because it has been reported to provide prognostic information regarding the risk for heart diseases. Sodium methoxide has been widely used for the determination of ω -3 fatty acids in food samples. This study demonstrates that sodium methoxide can be used effectively in RBC fatty acid profiling and determination of the ω-3 index. Briefly, the fatty acid profiles and ω-3 index of red blood cell samples were analyzed and results compared using three different methods: a two- step extraction and methylation method described by Hara and Radin, a single step extraction and methylation method described by Harris et al. and the sodium methoxide method. Our results revealed that there were no statistically significant differences (p<0.05) between the three methods for the representative fatty acids, [16:0 (p = 0.10), 18:0 (p=0.40), 18:1(ω9) (p = 0.29), 18:2(ω6) (p = 0.95), 18:3(ω3) (p = 0.50), 20:5(ω3) (p=0.56), 22:6(ω3) (p = 0.06)] and ω-3 index (p = 0.11) except for 20:4(ω6), (P = 0.02). In conclusion, we show that sodium methoxide can be used effectively in a one-step extraction and methylation procedure for high throughput analysis of fatty acids in red blood cell membranes. It is rapid (10 minute extraction and methylation), simple, safer than and as accurate as other commonly reported methods.

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Temesgen, Melese, Negussie Retta, and Etalem Tesfaye. "AMINO ACID AND FATTY ACID COMPOSITION OF ETHIOPIAN TARO." American Journal of Food Sciences and Nutrition 3, no. 1 (October 5, 2017): 46–58. http://dx.doi.org/10.47672/ajfsn.217.

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The purpose of this study was designed to investigate the amino acid and fatty acid composition of taro leaf and corm samples. An UHPLC and GC-FID method was used for the determination of amino acids and fatty acid composition, respectively. Taro leaf was processed as a powder and pre-curd concentrates while the corm was pre-gelatinized with and without peel prior to the analysis. The amino acid and fatty acid composition (%) of the analyzed samples were quantified with their relative area comparing with respective standards. In the present study, the leaf and corm of taro contained the three essential amino acids leucine, lysine and methionine. For the study, the calculated amino acid values were low in corm samples, but amino acid composition was higher in the leaf samples. Concerning fatty acids, the dominant fatty acid in the leaf and corm was oleic acid (C18:1, n-9) which ranged from 140.697 ± 0.054 to 216.775 ± 0.043 and 101.932 ± 0.023 to 101.950 ± 0. 04 mg/100 g, respectively. In the study, the fatty acid compositions in leaf were higher than the corm. This means that taro leaf would be considered as a good source of essential amino acid and fatty acid than the corm. Finally, from the proportion (mg/100 g) of saturated, monounsaturated and polyunsaturated fatty acids, the unsaturated fatty acids were the predominant fatty acids observed. The presence of high levels of unsaturated fatty acids in the entire investigation of our study taro is nutritionally rich.

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Ch, Muhammad Ishtiaq, Yang F. Wen, and YiYu Cheng. "Gas Chromatographic/Mass Spectrometric Analysis of the Essential Oil of Houttuynia cordata Thunb by Using On-Column Methylation with Tetramethylammonium Acetate." Journal of AOAC INTERNATIONAL 90, no. 1 (January 1, 2007): 60–67. http://dx.doi.org/10.1093/jaoac/90.1.60.

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Abstract This paper describes a simple and novel on-column derivatization procedure used with gas chromatography/mass spectrometry (GC/MS) for the analysis of essential oil of Houttuynia cordata Thunb (HCT), a traditional Chinese medicine. In the procedure, the essential oil was obtained by hydrodistillation, and the fatty acid components were derivatized with tetramethylammonium acetate (TMAA) at 250°C and identified by GC/MS. Methylation improved the determination of both the fatty acids and the other components in the essential oil of HCT. To obtain optimum methylation conditions, several important factors were investigated with pentadecane as the internal standard and a GC inlet temperature of 250°C. Tetramethylammonium hydroxide (TMAH) and TMAA were compared as the derivatization agent, and a 2:1 ratio of TMAA to capric acid was evaluated. Fatty acid methyl esters produced good chromatographic peak shapes and did not interfere with the determination of dodecanal and caryophyllene. TMAA is a neutral methylation reagent, and it yielded no side reactions during derivatization. It was found that the fatty acid content of the essential oil was about 81%; among the methylated fatty acids found were capric acid, methyl (43.66%), methyl laurate (16.15%), methyl hexadecanoate (9.27%), undecanoic acid, methyl (5.62%), methyl oleate (1.98%), and methyl linoleate (1.40%). Other major constituents were (-)-β-pinene (1.02%), β-myrcene (1.62%), 1-terpinen-4-ol (1.59%), decanal (1.49%), and 2-undecanone (1.47%). The results obtained demonstrated good efficiency for the procedure. Pure chromatograms allowed quantitation, which was obtained by total volume integration. The on-column derivatization procedure was simple to perform, and it improved the sensitivity, the peak resolution, and the selectivity of the GC/MS determination.

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Gorodyska, Olena, Nataliya Grevtseva, Olga Samokhvalova, and Sergey Gubsky. "DETERMINATION OF THE CHEMICAL COMPOSITION OF GRAPE SEED POWDERS BY GC-MS ANALYSIS." EUREKA: Life Sciences 6 (November 30, 2018): 3–8. http://dx.doi.org/10.21303/2504-5695.2018.00780.

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Substantiation of the expedience of using of natural antioxidants for inhibiting of oxidative and hydrolytic rancidity in confectionary industry is an urgent direction. The offered way of solving the problem is to use a fat-less grape seed powder, a product, obtained as wastes of vine-making as a source of antioxidants. For this aim, there were realized experimental studies of water-alcohol extracts (ethanol, isopropanol) by the method of gas chromatography with mass-spectroscopic detection (CG-MS) of the chemical composition of grape seed powders under industrial conditions. The obtained data allowed to establish that the studied extracts contain an essential amount of phenol compounds of the different origin: aromatic acids – gallic and egallic acids; resveratrol; flavonoids – quercetin and its derivatives, catechine, epicatechine, campferol and others alongside with esters of fatty acids. These components are strong antioxidants, and their introduction to a grape seed powder must favor inhibition of the oxidizing process of fats in fat-containing confectionary products, so increasing shelf-life of products.

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Martinez-Force, E., and R. Garcés. "Metabolic control analysis of de novo sunflower fatty acid biosynthesis." Biochemical Society Transactions 28, no. 6 (December 1, 2000): 669–71. http://dx.doi.org/10.1042/bst0280669.

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We have obtained a simulation of the final steps of de novo fatty acid biosynthesis in sunflower control line RHA-274. For this simulation, we have used data from the evolution of fatty acids during seed formation and from the biochemical characterization of β-keto-acyl-ACP synthetase II (FASII), stearoyl-ACP desaturase (SAD) and acyl-ACP thioesterase activities and the program GEPASI (based on the metabolic control-analysis theory). When physiological data from high- and mediumstearic acid mutants seed development were used with this model the predicted changes in SAD and TE were very similar to those actually found in the biochemical characterization of these mutants. However, the model had to be modified when results from high-palmitic mutants, accumulating unusual fatty acids like palmitoleic, asclepic and palmitolinoleic acids, were used. The emerging model, that fits all of our results, predicts the existence of a dynamic channelling between the FASII complex and SAD, that channelling being responsible for the alternative pathway starting with the desaturation of palmitic acid by the stearoyl-ACP desaturase. This channelling is consistent with our previous results. For instance, the determination of SAD activity on sunflower seed crude extracts only rendered oleic acid when the stearic acid used as a substrate was obtained from a KASII assay, but not when the stearic acid came from in vitro synthesis using acyl-ACP synthetase from Escherichia coli. This theoretical approximation will be very useful in predicting the evolution of the system when introducing new or modified activities; similar approximations in other oil-seed crops could be of great interest.

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Watanabe, Atsushi, Chu Watanabe, Robert Freeman, Mari Nakajima, Norio Teramae, and Hajime Ohtani. "QUANTITATIVE ANALYSIS OF FATTY ACIDS IN VULCANIZED STYRENE–BUTADIENE RUBBER BY THERMAL DESORPTION AND THERMALLY ASSISTED HYDROLYSIS AND METHYLATION-GC/MS." Rubber Chemistry and Technology 87, no. 3 (September 1, 2014): 516–25. http://dx.doi.org/10.5254/rct.14.86941.

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ABSTRACT Determination of stearic acid in rubber is very important from the viewpoint of quality control of products. In place of the conventional liquid-phase extraction procedures for the analysis of additives in rubber, stearic and palmitic acids in vulcanized styrene–butadiene rubber (SBR) samples were directly analyzed in the solid state by thermal desorption (TD)–gas chromatography (GC)/mass spectrometry (MS) and thermally assisted hydrolysis and methylation (THM)–GC/MS. It was found that the precision of analytical data was only fair in the TD-GC/MS analysis, with 7.8% relative standard deviation (RSD), because of the interaction between the polar fatty acids and basic sites in the GC chromatographic system. On the other hand, THM-GC/MS, in which the fatty acids are derivatized to the methyl esters using tetramethylammonium hydroxide, can overcome this problem. Under the optimized measurement conditions of this study for THM-GC/MS, the average determined value (0.62 wt%) of total fatty acids in the SBR samples was found to agree well with the compounded amount (0.64 wt%) used in the preparation stage of the SBR samples, and the RSD was 3.2%.

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Ha, Jaeho, Minseon Koo, and Hyunee Ok. "Determination of the Constituents of Sesame Oil by near Infrared Spectroscopy." Journal of Near Infrared Spectroscopy 6, A (January 1998): A371—A373. http://dx.doi.org/10.1255/jnirs.227.

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The important factors of sesame oil on its quality are acid value, peroxide value, and fatty acid composition. Acid value and peroxide value are determined by a wet analysis and fatty acid compositions by a gas chromatographic method. This study was carried out to ascertain the potential for utilizing NIR spectrophotometry as a means of rapid and non-destructive method to determine the constituent of sesame oil. Using both a fixed type and a grating-type device, the calibration obtained from the samples of sesame oil was successfully applied to the determination of the constituents such as acid value, peroxide value and fatty acids.

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Cañada, María Jose Ayora, Antonio Ruiz Medina, and Bernhard Lendl. "Determination of Free Fatty Acids in Edible Oils by Continuous-Flow Analysis with FT-IR Spectroscopic Detection." Applied Spectroscopy 55, no. 3 (March 2001): 356–60. http://dx.doi.org/10.1366/0003702011951777.

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A flow injection system with Fourier transform infrared spectroscopic detection was developed for the rapid determination of the free fatty acid content in edible oils. The method is based on complete deprotonation of the free fatty acids and evaluation of the intensity of the vas-(COO−) band formed at 1570 cm−1 with respect to a baseline point at 1534 cm−1. Upon deprotonation the absorption of the carboxylic acid moieties is shifted toward lower frequency, thus avoiding spectral interferences of the v-C=O from esters, ketones, or aldehydes also present in the sample. Optimum operational conditions were obtained by merging the sample stream first with a carrier stream of 25% (v/v) toluene in 2-propanol followed by merging with a 0.3 M solution of KOH in the same solvent mixture and measurement of the obtained solution after a short (2 s) reaction time. In this way saponification of the oil could be reduced to a minimum, whereas deprotonation was already completed. The obtained calibration curve was linear from 0 to 2.5% oleic acid, and the coefficient of variation of the method was 3.3%. The developed method was applied to the determination of the total amount of free fatty acids in olive, sunflower, and corn oils, delivering results that were in good agreement with those obtained by the official reference method proposed by the European Community. Furthermore, due to its high degree of automation and throughput (40 samples h−1), the developed method is suitable for quality control in routine applications.

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Pavlík, Zdeněk, Alena Saláková, Josef Kameník, Jan Pospíšil, Michaela Králová, and Iva Steinhauserová. "Effect of micro-encapsulated n-3 fatty acids on quality properties of two types of dry sausages." Acta Veterinaria Brno 83, no. 2 (2014): 163–69. http://dx.doi.org/10.2754/avb201483020163.

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Dry sausages are popular traditional meat products. As these products are a rich source of animal fat, there is an effort to improve their fatty acid ratio. The aim of this work was to study the effect of micro-encapsulated n-3 fatty acids added into dry sausages. Samples of dry sausages (Poličan and Vysočina) enriched with unsaturated fatty acids (36 g for 6 kg of mixture) and rosemary extract (0.3 g·kg-1) were made along with control samples. Physicochemical, instrumental analyses were performed, fatty acid profile was measured by gas chromatography, and oxidation processes were monitored by determination of thiobarbituric acid reactive substances. No significant differences (P ≥ 0.05) in quality indicators were found between samples, however, there were differences in oxidation processes. Sausages enriched with unsaturated fatty acids showed an increase in thiobarbituric acid reactive substances (> 2 mg·kg-1 and > 3 mg·kg-1 in Poličan and Vysočina, respectively, compared to control). Sausages enriched with unsaturated fatty acids and also with rosemary extract have the similar concentration of thiobarbituric acid reactive substances as the control. An increase in the proportion of monounsaturated fatty acids and polyunsaturated fatty acids was seen in samples of Poličan supplemented with unsaturated fatty acids in combination with rosemary extract. The addition of rosemary extract had also a significant effect in increasing the proportion of unsaturated fatty acids in samples of Vysočina. From the viewpoint of quality indicators, changes in the properties of the product were not seen in any samples.

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Windham, William R., and W. H. Morrison. "Prediction of Fatty Acid Content in Beef Neck Lean by near Infrared Reflectance Analysis." Journal of Near Infrared Spectroscopy 6, no. 1 (January 1998): 229–34. http://dx.doi.org/10.1255/jnirs.141.

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Near infrared (NIR) spectroscopy in the prediction of individual and total fatty acids of bovine M. Longissimus dorsi neck muscles has been studied. Beef neck lean was collected from meat processing establishments using advanced meat recovery systems and hand-deboning. Samples ( n = 302) were analysed to determine fatty acid (FA) composition and scanned from 400 to 2498 nm. Total saturated and unsaturated FA values ranged from 43.2 to 62.0% and 38.3 to 56.2%, respectively. Results of partial least squares (PLS) modeling shown reasonably accurate models were attained for total saturate content [standard error of performance ( SEP = 1.10%); coefficient of determination on the validation set ( r2 = 0.77)], palmitic ( SEP = 0.94%; r2 = 0.69), unsaturate ( SEP = 1.13%; r2 = 0.77), and oleic ( SEP = 0.97; r2 = 0.78). Prediction of other individual saturated and unsaturated FAs was less accurate with an r2 range of 0.10 to 0.53. However, the sum of individual predicted saturated and unsaturated FA was acceptable compared with the reference method ( SEP = 1.10 and 1.12%, respectively). This study shows that NIR can be used to predict accurately total fatty acids in M. Longissimus dorsi muscle.

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Aziz, Abdul, and Faisal Abu-Dagga. "A Single Cell Protein as Standard Reference Material for Determination of Amino Acids, Fatty Acids, and Elements in Foods." Journal of AOAC INTERNATIONAL 74, no. 1 (January 1, 1991): 104–6. http://dx.doi.org/10.1093/jaoac/74.1.104.

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Abstract A commercially available single-cell protein (Pruteen) was analyzed for amino acids, fatty acids, and major, minor, and trace-element composition after storage at room temperature and at 4°C over a period of 5 years. The purpose was to assess its suitability as an organic-nutrient standard reference material for food analysis. The material showed longterm stability and is, therefore, recommended for interlaboratory certification studies.

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Zhizhin, N. A. "Application of the “fast” gas chromatography method for regular analysis of fatty acids in milk and dairy products." Proceedings of the Voronezh State University of Engineering Technologies 82, no. 1 (May 15, 2020): 164–68. http://dx.doi.org/10.20914/2310-1202-2020-1-164-168.

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The paper presents one of the approaches for identifying fatty acids using gas chromatography, which significantly reduces the analysis time, and is equally effective when compared with the traditional method of studying the fatty acid composition. The determination of the composition of fatty acids today is a guarantee of quality in identifying various conformations and modifications of milk fat, the bioactive properties of individual acids of the omega-3 and omega-6 families, etc. Moreover, this method is time-consuming, therefore, the goal of this work is to optimize the parameters of this methodology for quick and regular analysis of fatty acid composition in laboratories and dairy enterprises. The analysis of the fatty acid composition was carried out using two columns with different stationary phases. A comparative evaluation of the analytical characteristics was carried out on two capillary chromatographic columns: SP-2560 100 ? 0.25 mm ID, 0.2 ?m with a stationary phase FFAP (traditional) and a gas chromatographic column BPX-70: stationary phase 70% cyanopropylphenyl dimethylpolysiloxane, 10 m ? 0.1 m ? 0.20 ?m. Detection was carried out using a flame ionization detector. A mixture of Supelco® 37 FAME Mix fatty acid methyl esters and Sigma-Aldrich methyl decanoate analytical standard was used as the standard. For data processing, the NetChrom software was used, the composition of fatty acid methyl esters was calculated by the internal normalization method. The analysis time of the first column was 49.07 minutes, for the second 8.44, respectively. The use of a stationary phase column of cyanopropylphenyl dimethylpolysiloxane significantly reduced the analysis time when eluting a complex composition of fatty acids. The studies were carried out using modern analytical techniques and arbitration methods of analysis in the laboratory of technochemical control of the All-Russian Scientific Research Institute of the Dairy Industry. This adapted analysis method will be of interest to specialists in the field of laboratory research and processing enterprises.

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SHIBAHARA, Akira, Kohei YAMAMOTO, Takao NAKAYAMA, and Goro KAJIMOTO. "Rapid Determination of Double Bond Positions in Monounsaturated Fatty Acids by GC-MS and Its Application to Fatty Acid Analysis." Journal of Japan Oil Chemists' Society 34, no. 8 (1985): 618–25. http://dx.doi.org/10.5650/jos1956.34.618.

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CHAVARRI, FELISA, MAILO VIRTO, CELIA MARTIN, ANA I. NÁJERA, ARANTZA SANTISTEBAN, LUIS J. R. BARRÓN, and MERTXE DE RENOBALES. "Determination of free fatty acids in cheese: comparison of two analytical methods." Journal of Dairy Research 64, no. 3 (August 1997): 445–52. http://dx.doi.org/10.1017/s0022029997002197.

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Two methods were compared for the determination of free fatty acids (FFA) from acetic to long-chain acids in samples with a large excess of triacylglycerols (TG) (1[ratio ]200, w/w), such as cheese and other dairy products. In method 1, after fat extraction, FFA were separated from TG by aminopropyl-bonded phase chromatography, injecting the fraction containing FFA directly into the gas chromatograph. In method 2, extracted fat was treated with tetramethylammonium hydroxide, the methyl ester derivatives being formed in the injector. Cheese samples and standard mixtures of FFA and TG in different proportions were analysed by both methods. The cheese sample contained 2·4 times more FFA when analysed by method 2 as compared with the result obtained with method 1. The composition of the standard mixtures analysed by method 1 closely reflected that of the original mixture and gave 90–100% recovery of FFA, regardless of their chain length and the ratio of FFA[ratio ]TG (1[ratio ]1 or 1[ratio ]200, w/w). The composition of samples with a FFA[ratio ]TG ratio of 1[ratio ]200 (w/v) was severely distorted (as compared with the original composition of the sample) when analysed by method 2. Varying recoveries of FFA were also obtained, the largest differences being found for the shorter-chain components. We conclude that the FFA fraction should be separated from the TG fraction before derivatization and chromatographic analysis, particularly for samples in which the FFA represent a minor fraction of the TG.

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DOGARIS, IOANNIS, MIKAEL LINDSTROM, and GUNNAR HENRIKSSON. "Critical parameters for tall oil separation I: The importance of the ratio of fatty acids to rosin acids." TAPPI Journal 18, no. 9 (October 1, 2019): 547–55. http://dx.doi.org/10.32964/tj18.9.547.

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Tall oil is a valuable byproduct in chemical pulping of wood, and its fractions have a large spectrum of applications as chemical precursors, detergents, and fuel. High recovery of tall oil is important for the economic and environmental profile of chemical pulp mills. The purpose of this study was to investigate critical parameters of tall oil separation from black liquor. To investigate this in a controlled way, we developed a model test system using a “synthetic” black liquor (active cooking chemicals OH- and HS- ions), a complete process for soap skimming, and determination of recovered tall oil based on solvent extraction and colorimetric analysis, with good reproducibility. We used the developed system to study the effect of the ratio of fatty acids to rosin acids on tall oil separation. When high amounts of rosin acids were present, tall oil recovery was low, while high content of fatty acids above 60% significantly promoted tall oil separation. Therefore, manipulating the content of fatty acids in black liquor before the soap skimming step can significantly affect the tall oil solubility, and hence its separation. The findings open up chemical ways to improve the tall oil yield.

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Journal articles on the topic 'Fatty acids (Analysis; Determination)'

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