C<sub>18</sub>‐saturated cyclic acids from linseed oil: A structural study

Friedrich, J. P.

doi:10.1007/bf02639267

Cited by 31 publications

(11 citation statements)

References 18 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…ST A simple fragmentation was obtained for the CFAM 9T with a 6-carbon membered ring ( Table 4, peaks 6-4 and 10T 7-4). The different fragments observed (A,B,C and D) corresponded to a fragmentation in the a position as previously described (5,6,16). In that case, the fragment B + i was always more intense than the fragment B.…”

supporting

confidence: 74%

See 1 more Smart Citation

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Sébédio

Quéré²,

Sémon³

et al. 1987

J Americ Oil Chem Soc

View full text Add to dashboard Cite

Gas liquid chromatography coupled with mass spectrometry (GC-MS} showed that the cyclic fatty acid monomers tCFAM) isolated from a heated linseed oil have two ethylenic bonds, while the CFAM isolated from heated sunflower oils were saturated and monoethylenic isomers. GC-MS studies also showed the presence of cyclohexenic derivatives in the case of linseed oil.GLC coupled with Fourier transform infrared spectrometry IGC-FTIR) studies indicated that the CFAM isolated from linseed oil were of cis (Z), trans (E) structures except two components which were cis, cis {Z,Z) dienoic acids. The unsaturated CFAM isolated from sunflower oils were cis (Z) and trans {E) monoethylenic isomers. For sunflower oils, the major CFAM were isomers having a cis {Z) ethylenic bond. The saturated CFAM isolated from a heated sunflower oil had molecular weights of 296 and 294. The latter could correspond to some bicyclic isomers.Fractions containing 97-99% of cyclic fatty acid monomers have been isolated from heated linseed and sunflower oils {1,2). A combination of column chromatography, urea adduct fractionation and high performance liquid chromatography (HPLC) was used to isolate these components.In order to know the structure of a cyclic fatty acid, one has to determine the size of the ring, the nature of the substituents, the degree of unsaturation and the position and geometry of the ethylenic bonds. The size of the ring and the nature of the substituents usually are determined by gas liquid chromatography coupled with mass spectrometry, GC-MS (3-9) after total hydrogenation on platinum oxide. The position of the ethylenic bonds can be determined by GC-MS of the trimethylsilyl (TMS) derivatives (10). We are reporting the determination of the degree of unsaturation of the isolated cyclic fatty acid monomers by GC-MS and the geometry of the ethylenic bonds by GC coupled with Fourier transform infrared spectrometry (GC-FTIR). The cyclic fatty acid monomers isolated from a heated linseed oil appeared to have two ethylenic bonds, while the cyclic fatty acid monomers isolated from heated sunflower oils were saturated and monoethylenic isomers. The CFAM isolated from linseed oil were of cis (Z), trans (E) structures except for two components. Both cis (Z) and trans {E) monoethylenic CFAM were found in fractions isolated from sunflower oils. MATERIALS AND METHODS Gas liquid chromatography-mass spectrometry (GC-MS).All the GC-MS analyses were performed using a Ribermag R10-10C quadrupole mass spectrometer coupled to a Girdel 31 gas chromatograph fitted with a split-splitless injector and a Chrompack fused-silica capillary column (26 m X 0.32 mm i.d., stationary bonded phase: 1.2 ~m of CpWax 57 CB). Helium was used as the carrier gas at a flow rate of one ml/min. The injection port was maintained at 240 C, and splitless injections (1 t~l) of hexane solutions were used.The transfer line, consisting of a deactivated fused-silica capillary column (50 cm X 0.32 mm i.d.) connected to the analytical column with a zero-dead volume capillary buttconn...

show abstract

supporting

confidence: 74%

“…The characteristic A-D fragmentations for cyclic esters (5,6,16) were observed (Fig. 2, m/z 43, 124, 168, 249).…”

mentioning

confidence: 95%

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Sébédio

Quéré²,

Sémon³

et al. 1987

J Americ Oil Chem Soc

View full text Add to dashboard Cite

show abstract

“…Several decades ago, it was suspected that unsaturated cyclic fatty acid monomers (CFAM) are formed in frying oils. Consequently, several attempts were made to elucidate their structures by various analytical techniques (1)(2)(3)(4)(5)(6)(7)(8)(9)(10). CFAM, which are reported to be potentially toxic (6,(11)(12)(13) and are readily absorbed by the digestive system (14,15), were found at levels up to 0.5% in frying oils collected from restaurants in the United States (16).…”

Section: Lipids 29 893-896 (1994)mentioning

confidence: 99%

Rapid determination of double bond configuration and position along the hydrocarbon chain in cyclic fatty acid monomers

Mossoba

Yurawecz

Roach

et al. 1994

Lipids

View full text Add to dashboard Cite

This study reports the structural elucidation of diunsaturated 5- or 6-membered ring cyclic fatty acid monomers (CFAM) isolated from heated flaxseed oil by complementary gas chromatography (GC)-mass spectrometry (MS) and GC-matrix isolation-Fourier transform infrared spectroscopy (MI-FTIR). Infrared measurements of CFAM were carried out on methyl ester derivatives as well-resolved chromatograms were obtained on a polar 100% cyanopropyl polysiloxane capillary GC column. By contrast, electron ionization MS of methyl ester derivatives was of limited value because of double bond migration during the ionization process in the mass spectrometer. This communication reports definitive MS fragmentation patterns that can confirm ring position and double bond position along the fatty acid chain in 1,2-disubstituted CFAM determined as 2-alkenyl-4,4-dimethyl-oxazoline derivatives. Double bond configuration (cis, trans, or conjugated cis,cis) in CFAM was confirmed by GC-MI-FTIR. The presence of CFAM, degradation products found in used frying oils, is a potential source of dietary toxicity.

show abstract

“…Synthetic triglycerides containing a cyclic monomeric acid. All syntheses were done by ing to Friedrich (23). Its purity (> 98%) was verified by gas liquid chromatography (GLC) and its structure confirmed by infrared (IR) spectroscopy and nuclear magnetic resonance (NMR).…”

Section: Dietary Fatsmentioning

confidence: 99%

Lymphatic absorption of nonvolatile oxidation products of heated oils in the rat

Combe

Constantin

Entressangles

1981

Lipids

View full text Add to dashboard Cite

The lymphatic absorption of nonvolatile oxidation products (NVOP) formed during heating of fats was studied. Heated colza or soybean oils or synthetic triglycerides containing a definite aromatic or alicyclic fatty acid were fed to thoracic duct-cannulated rats. Tritium-labeled triolein was added to each dietary fat, as an internal standard, in order to calculate the percentage of lymphatic absorption of the ingested NVOP. Results show that 4% of the total polymeric acids, 53% of the total oxidized monomeric acids and 96% of the total cyclic monomeric acids were recovered in the lymphatic lipids. Gas liquid and quantitative thin layer chromatography of these 3 classes indicated that, within a NVOP class, the various constituents did not present the same absorption rate. The lymphatic absorptions of individual oxidized monomers were between 25 and 93%. Concerning the polymer fraction, the lymphatic recoveries were 1% (nonpolar dimers), 6.8% (polar dimers) and 12% (polar oligomers). Aromatic acids were absorbed to a lesser degree (50-60%) than cyclohexenic acids (91-98%).

show abstract

C₁₈‐saturated cyclic acids from linseed oil: A structural study

Cited by 31 publications

References 18 publications

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Rapid determination of double bond configuration and position along the hydrocarbon chain in cyclic fatty acid monomers

Lymphatic absorption of nonvolatile oxidation products of heated oils in the rat

Contact Info

Product

Resources

About

C18‐saturated cyclic acids from linseed oil: A structural study

Cited by 31 publications

References 18 publications

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Heat treatment of vegetable oils. II. GC‐MS and GC‐FTIR spectra of some isolated cyclic fatty acid monomers

Rapid determination of double bond configuration and position along the hydrocarbon chain in cyclic fatty acid monomers

Lymphatic absorption of nonvolatile oxidation products of heated oils in the rat

Contact Info

Product

Resources

About

C₁₈‐saturated cyclic acids from linseed oil: A structural study