Direct determination of saturated fatty acids in fats, oils, and methyl esters

1958 ◽  
Vol 35 (1) ◽  
pp. 41-45 ◽  
Author(s):  
D. F. Kuemmel
Marine Drugs ◽  
2020 ◽  
Vol 18 (3) ◽  
pp. 169
Author(s):  
Roberto Barone ◽  
Lorenzo De Napoli ◽  
Luciano Mayol ◽  
Marina Paolucci ◽  
Maria Grazia Volpe ◽  
...  

Algae have multiple similarities with fungi, with both belonging to the Thallophyte, a polyphyletic group of non-mobile organisms grouped together on the basis of similar characteristics, but not sharing a common ancestor. The main difference between algae and fungi is noted in their metabolism. In fact, although algae have chlorophyll-bearing thalloids and are autotrophic organisms, fungi lack chlorophyll and are heterotrophic, not able to synthesize their own nutrients. However, our studies have shown that the extremophilic microalga Galderia sulphuraria (GS) can also grow very well in heterotrophic conditions like fungi. This study was carried out using several approaches such as scanning electron microscope (SEM), gas chromatography/mass spectrometry (GC/MS), and infrared spectrophotometry (ATR-FTIR). Results showed that the GS, strain ACUF 064, cultured in autotrophic (AGS) and heterotrophic (HGS) conditions, produced different biomolecules. In particular, when grown in HGS, the algae (i) was 30% larger, with an increase in carbon mass that was 20% greater than AGS; (ii) produced higher quantities of stearic acid, oleic acid, monounsaturated fatty acids (MUFAs), and ergosterol; (iii) produced lower quantities of fatty acid methyl esters (FAMEs) such as methyl palmytate, and methyl linoleate, saturated fatty acids (SFAs), and poyliunsaturated fatty acids (PUFAs). ATR-FTIR and principal component analysis (PCA) statistical analysis confirmed that the macromolecular content of HGS was significantly different from AGS. The ability to produce different macromolecules by changing the trophic conditions may represent an interesting strategy to induce microalgae to produce different biomolecules that can find applications in several fields such as food, feed, nutraceutical, or energy production.


Weed Science ◽  
1992 ◽  
Vol 40 (4) ◽  
pp. 558-562 ◽  
Author(s):  
Frank A. Manthey ◽  
Edward F. Szelezniak ◽  
Zbigniew M. Anyszka ◽  
John D. Nalewaja

Experiments were conducted to determine the effect of triglycerides, free fatty acids (FFA), and fatty acid methyl esters (FAME) on the foliar absorption, translocation, and phytotoxicity of quizalofop. Absorption, translocation, and phytotoxicity of quizalofop in oats were greater when quizalofop was applied with FFA or FAME than with their respective triglycerides. Triglycerides and FFA generally enhanced quizalofop absorption and translocation more when they contained unsaturated than saturated fatty acids. Methylation of the fatty acids reduced differences among fatty acids, but methyl stearate and methyl linolenate enhanced absorption of quizalofop less than the other FAME for oats and yellow foxtail. Quizalofop absorption and phytotoxicity to oats were greater when applied with sunflower oil, sunflower oil FFA, and sunflower oil FAME than with the corresponding linseed oil derivatives. Emulsifier generally reduced differences between linseed oil and sunflower oil derivatives in their enhancement of absorption, translocation, and phytotoxicity of quizalofop.


1971 ◽  
Vol 54 (6) ◽  
pp. 1288-1292
Author(s):  
Anita Huang ◽  
David Firestone

Abstract A study was made to compare the rapid method reported by Allen with the tentative method of the American Oil Chemists’ Society for the determination of isolated (unconjugated) trans isomers of unsaturated fatty acids. The rapid method was found to be less accurate. The accuracy of the rapid method can be improved by using an oil or methyl ester matrix with the same composition as the sample matrix for the determination of K-and f-values used for calculation of per cent trans isomers. Results obtained with both methods for methyl esters were more accurate than results for vegetable oils. An analysis of variance was performed to compare the methods.


2019 ◽  
Vol 3 (Supplement_1) ◽  
Author(s):  
Sesha Durga Kumar Kothapalli ◽  
Zhen Wang ◽  
Dong Hao Wang ◽  
Hui Gyu Park ◽  
Yuanyuan Yan ◽  
...  

Abstract Objectives Saturated branched chain fatty acids (BCFA) terminating with either an isopropyl or sec-butyl group, are common bioactive food components consumed from beef, fish, and dairy products. Little is known about their endogenous metabolism and the enzymes mediating their interconversion. Our main objective was to test the substrate specificity of the fatty acid elongases (ELOVL1–7) towards elongation of representative BCFA, anteiso-15:0 and iso-18:0. We also assessed competition between BCFA and normal saturated fatty acid (n-SFA). Methods MCF7 human breast cancer cells are used for functional studies. PcDNA3.1 expression vector was used to clone seven open reading frames of ELOVL transcripts (ELOVL1–7). MCF7 cells were transiently transfected with specific ELOVL1–7 transgene vector or empty vector (control). After 24 h incubation, the transfected MCF7 cells were treated with BSA-bound substrates. After additional 24 h incubation, cells were harvested by trypsinization, fatty acid methyl esters prepared and analyzed quantitatively by GC-FID. Fatty acid composition was characterized by gas chromatography (GC) –electron ionization mass spectrometry (EIMS) and EIMS/MS for branched carbon chain. Results Transient transfection of ELOVL1–7 into MCF7 cells show that ELOVL6 had highest activity towards elongation of anteiso-15:0→anteiso-17:0, followed by ELOVL5 which showed moderate activity. ELOVL3 was found to be most active ELOVL mediating elongation of iso-18:0→iso-20:0. Our competition results show in ELOVL6 cells anteiso-15:0 competes with n-SFA n-16:0, whereas, in ELOVL3 cells iso-18:0 competes with n-18:0. Conclusions The elongation of anteiso-15:0 and iso-18:0 BCFA is predominantly operated by the ELOVL6 and ELOVL3, respectively that are well known to operate on normal saturated fatty acids, rather than the ELOVL2 and ELOVL5 which operate on lower-melting polyunsaturated fatty acids. The competition between BCFA and n-SFA for ELOVL1–7 mediated elongation may have implications in the skin, sebaceous, and meibomian glands where both normal and BCFA are present at comparable levels. Funding Sources NIH grant R01 AT007003.


1986 ◽  
Vol 69 (1) ◽  
pp. 65-67
Author(s):  
Albert K Athnasios ◽  
Edward J Healy ◽  
Anthony F Gross ◽  
Gareth J Templeman

Abstract A capillary gas chromatographic (CGC) method is described for the determination of cis,cis-methylene interrupted polyunsaturated fatty acids (cis-PUFA) in fats and oils. The sample is saponified and the liberated fatty acids are esterified to the corresponding methyl esters. The latter are analyzed by CGC using a 60M SP2340 capillary column. Area percent values for 9,12-cis,cis-C18:2 and 9,12,15-cis,cis,cis-C18:3 fatty acid methyl esters are summed to give the total cis-PUFA content. Gas chromatographic results agreed well with those obtained by an enzymatic lipoxygenase method at the 31-48% cis-PUFA levels with a correlation coefficient of 0.98. The method has a precision (relative standard deviation) of 0.33% at a 44.4% cis-PUFA level in margarine oil.


Plant Disease ◽  
2000 ◽  
Vol 84 (7) ◽  
pp. 785-788 ◽  
Author(s):  
R. E. Baird ◽  
R. D. Gitaitis ◽  
D. E. Carling ◽  
S. M. Baird ◽  
P. J. Alt ◽  
...  

Fatty acid methyl esters (FAMEs) of isolates of Rhizoctonia solani AG-4 and AG-7 were characterized by gas chromatography and analyzed with Microbial Identification System software. Palmitic, stearic, and oleic acids were common in all isolates from both anastomosis groups (AGs) and accounted for 95% of the C14 to C18 fatty acids present. Oleic acid, most common in both R. solani AG-4 and AG-7 isolates, accounted for the greatest percentages of total FAMEs. The presence, quantities, or absence of individual fatty acids could not be used for distinguishing AG-4 and AG-7 isolates. Anteisopentadecanoic and 9-heptadecanoic acids, however, were specific to all three AG-7 isolates from Japan but absent in other AG-7 isolates and all AG-4 isolates. Pentadecanoic acid occurred in only two of the R. solani AG-4 isolates, but was not found in any of the AG-7 isolates. The AG-4 isolates could be distinguished from AG-7 isolates when quantities of FAMEs and key FAME ratios were analyzed with cluster analysis and principle components were plotted. Isolates of AG-7 from Arkansas, Indiana, and Georgia appeared to be more closely related to each other than to AG-7 isolates from Japan and Mexico. These differences in FAMEs were sufficiently distinct that isolate geographical variability could be determined. A dendrogram analysis cluster constructed from the FAMEs data showed results similar to that of the principal component analysis. Euclidean distances of total AG-4 isolates were distinct from total AG-7 isolates. The Arkansas and Indiana AG-7 isolates had a similar Euclidean distance to each another but the percentages were different for the AG-7 isolates from Japan and Mexico. In conclusion, variability of the FAMEs identified in this study would not be suitable as the main diagnostic tool for distinguishing individual isolates of R. solaniAG-4 from AG-7.


1976 ◽  
Vol 59 (4) ◽  
pp. 855-858
Author(s):  
Jean P Barrette

Abstract A rapid gas-liquid chromatographic (GLC) procedure was developed for the determination of C22 fatty acids (mostly erucic acid) in rapeseeds containing less than 5% erucic acid. The method involves an oil extraction from a representative sample of rapeseeds, a vigorous boron trifluoride-methanol transesterification of the oil to methyl esters, and analysis by GLC with the aid of an electronic integrator. Six laboratories participated in a monthly check sample program. By adjusting the GLC detector response with 2 synthetic reference standard mixtures containing 1.0 and 3.0% methyl behenate, interlaboratory agreement within 0.3% C22 was consistently obtained.


2015 ◽  
Vol 4 (2) ◽  
Author(s):  
Monica Panozzo ◽  
Luciano Magro ◽  
Ilario Erle ◽  
Stefano Ferrarini ◽  
Riccardo Murari ◽  
...  

The sampling activity for this study was performed between September and October 2012. It involved seven shops in Verona, eleven in Vicenza and two in its province (Bassano del Grappa), northern Italy. The scope was to measure the values of energy and nutritional components and to identify the profile of fatty acids in a serving of ready to eat Döner Kebab. The samples were collected according to the usual proportions of this preparation, keeping all the components (bread, meat, vegetables and sauces) separated in different bags. In the laboratory, each component was weighed and, after pooling, processed for the analytical determination of humidity, crude protein, lipid content and fatty acid profile, ashes, sodium (salt), carbohydrate, collagen (measured only in meat) and fibre. The results showed a highly standardized recipe, while the comparison between the two towns showed a significant difference in carbohydrate concentration (mainly due to the quantity of bread used). By observing data on the serving sizes sampled (274 to 618 g) and the nutritional values obtained, Döner Kebab can be seen as a ready to eat dish providing much energy: on average a serving size covers 45 and 36% of the recommended daily intake of energy, 95.7 and 82.1% of protein, 42.5 and 33.4% of saturated fatty acids for females and males, respectively, and 85.5% of salt regardless of gender. Döner Kebab can be considered as an occasional substitute to one of the two main meals of the day.


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