An Evaluation of Five Methods for the Quantitative Determination of Cyclopropenoid Fatty Acids

1970 ◽  
Vol 53 (6) ◽  
pp. 1209-1213
Author(s):  
Eugene C Coleman
Keyword(s):  
Fatty Acids ◽  
Silver Nitrate ◽  
Hydrobromic Acid ◽  
Internal Standard ◽  
Cyclopropenoid Fatty Acid ◽  
Titration Method ◽  
Cyclopropenoid Fatty Acids ◽  
Peak Area Normalization ◽  
Back Titration

Abstract An evaluation of 5 methods for determining 5% or less cyclopropenoid fatty acids was made in terms of accuracy, precision, and sensitivity. GLC of the methyl mercaptan derivatives of cyclopropenoid fatty acids and titration with hydrobromic acid in toluene were found to be unsuitable. GLC of the silver nitratemethanol derivatives (quantitation by an internal standard) and titration with hydrobromic acid in acetic acid were equally precise, and the former required less sample; however, both methods gave low recoveries. GLC of silver nitrate-methanol derivatives (quantitation by peak area normalization) and a hydrobromic acid-benzene back-titration method gave good recoveries. The Halphen test was found to be the best general method when calibrated with a cyclopropenoid fatty acid standard analyzed by the silver nitrate-methanol GLC method (quantitation by peak area normalization) or the hydrobromic acid-benzene back-titration method.

scholarly journals Exploitation of HPLC Analytical Method for Simultaneous Determination of Six Principal Unsaturated Fatty Acids in Oviductus Ranae Based on Quantitative Analysis of Multi-Components by Single-Marker (QAMS)

Molecules ◽  
2021 ◽  
Vol 26 (2) ◽  
pp. 479
Author(s):  
Shihan Wang ◽  
Yuanshuai Gan ◽  
Hong Kan ◽  
Xinxin Mao ◽  
Yongsheng Wang
Keyword(s):  
Fatty Acids ◽  
Quantitative Analysis ◽  
Unsaturated Fatty Acids ◽  
Internal Standard ◽  
Active Components ◽  
Reliable Determination ◽  
External Standard Method ◽  
Single Marker ◽  
Oviductus Ranae

As one of the featured products in northeast China, Oviductus Ranae has been widely used as a nutritious food, which contains a variety of bioactive unsaturated fatty acids (UFAs). It is necessary to establish a scientific and reliable determination method of UFA contents in Oviductus Ranae. In this work, six principal UFAs in Oviductus Ranae, namely eicosapentaenoic acid (EPA), linolenic acid (ALA), docosahexaenoic acid (DHA), arachidonic acid (ARA), linoleic acid (LA) and oleic acid (OA), were identified using UPLC-MS/MS. The UFAs identified in Oviductus Ranae were further separated based on the optimized RP-HPLC conditions. Quantitative analysis of multi-components by single-marker (QAMS) method was implemented in content determination of EPA, ALA, DHA, ARA and OA, where LA was used as the internal standard. The experiments based on Taguchi design verified the robustness of the QAMS method on different HPLC instruments and chromatographic columns. The QAMS and external standard method (ESM) were used to calculate the UFA content of 15 batches of Oviductus Ranae samples from different regions. The relative error (r < 0.73%) and cosine coefficient showed that the two methods obtained similar contents, and the method validations met the requirements. The results showed that QAMS can comprehensively and effectively control the quality of UFAs in Oviductus Ranae which provides new ideas and solutions for studying the active components in Oviductus Ranae.

A modified two-point titration method for the determination of volatile fatty acids in anaerobic systems

Chemosphere ◽  
2018 ◽  
Vol 204 ◽  
pp. 251-256 ◽  
Author(s):  
Zhe-Xuan Mu ◽  
Chuan-Shu He ◽  
Jian-Kai Jiang ◽  
Jie Zhang ◽  
Hou-Yun Yang ◽  
...  
Keyword(s):  
Fatty Acids ◽  
Volatile Fatty Acids ◽  
Titration Method

Quantitative Gas-Chromatographic Determination of Short-Chain Fatty Acids in Aqueous Samples

1974 ◽  
Vol 20 (9) ◽  
pp. 1235-1237 ◽  
Author(s):  
Dennis P Collin ◽  
Patrick G McCormick ◽  
Milton G Schmitt
Keyword(s):  
Fatty Acids ◽  
Free Acid ◽  
Internal Standard ◽  
Short Chain Fatty Acids ◽  
Chromatographic Determination ◽  
Short Chain ◽  
Aqueous Samples ◽  
Peak Areas ◽  
Chain Fatty Acids

Abstract We report the use of SP-1200 (Supelco Inc.) for quantitative gas-chromatographic determination of short-chain fatty acids (C2-C5) in stool water. The ratio of peak areas for these acids to that for 2-methylvaleric acid (internal standard) is linear for each acid from 60 to 1800 mg/liter. Lactic acid, occasionally present in stool in abnormally high amounts, is not detectable as the free acid on SP-1200, but is determined as its propyl ester on diethyleneglycolsuccinate.

Liquid Chromatographic Method for Quantitative Determination of Free Fatty Acids in Butter

1984 ◽  
Vol 67 (4) ◽  
pp. 718-721 ◽  
Author(s):  
Alan W Reed ◽  
Hilton C Deeth ◽  
Donald E Clegg
Keyword(s):  
Fatty Acids ◽  
Free Fatty Acids ◽  
Chromatographic Method ◽  
Water System ◽  
Internal Standard ◽  
Detection Range ◽  
Water Solvent ◽  
Liquid Chromatographic Method ◽  
Liquid Chromatographic

Abstract A liquid chromatographic method has been developed for the determination of free fatty acids in butter. The fatty acids are converted to the p-bromophenacyl esters, via a crown ether-catalyzed reaction, without separation from the other butter components. The esters are separated on a Cis-bonded silica column by using an acetonitrile-water solvent gradient and quantitated using the ester of heptadecanoic acid as internal standard. Cu, and C ,S:i co-elute in the acetonitrile-water system but are separated using an isocratic methanol-acetonitrile-water system. Limits of detection range from 7 ng for butyric acid to 45 ng for linoleic acid. The average coefficient of variation (n = 10) for 10 free fatty acids from,a butter was 5.83%.

scholarly journals Determination of Cyclopropenoid Fatty Acids in Ewe Milk Fat by GC-MS after Intravenous Administration of Sterculic Acid

Foods ◽  
2020 ◽  
Vol 9 (7) ◽  
pp. 901
Author(s):  
Veronica Lolli ◽  
Pablo G. Toral ◽  
Augusta Caligiani ◽  
Pilar Gómez-Cortés
Keyword(s):  
Fatty Acids ◽  
Milk Fat ◽  
Sterculic Acid ◽  
Bioactive Lipids ◽  
Cyclopropenoid Fatty Acids ◽  
Δ9 Desaturase ◽  
First Time ◽  
Endogenous Synthesis

Cyclopropenoid fatty acids (CPEFA), found in oilseeds from Malvaceae and Sterculiaceae, have been shown to interfere with the endogenous synthesis of several bioactive lipids of dairy fat, such as cis-9, trans-11 18:2 and cis-9 18:1, by inhibiting Δ9-desaturase. No previous study has reported the presence of sterculic acid in animal fat and its incorporation in tissues after its administration, due to the lack of a proper methodology. In the present research, a GC-MS method based on cold base derivatization to fatty acids methylesters was developed to determine CPEFA in ewe milk triglycerides, after infusing sterculic acid (0.5 g/day) to six lactating ewes. An alternative derivatization based on silanyzation followed by GC-MS analysis was also tested, showing its possible applicability when CPEFA are present in the form of free fatty acids. Sterculic acid was detected in ewe milk triglycerides, demonstrating its incorporation from the bloodstream into milk by the mammary gland. The mean transfer rate represented 8.0 ± 1.0% of the daily dose. This study provides, for the first time, the presence of sterculic acid in milk fat, supporting the importance of understanding its occurrence in vivo and encouraging further research to determine whether it can be present in foods, such as dairy products, obtained under practical farming conditions.

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