Comparison of Separation of Seed Oil Triglycerides Containing Isomeric Conjugated Octadecatrienoic Acid Moieties by Reversed-Phase HPLC

Abstract

Abstract:Relative retention analysis and increment approach were applied for the comparison of triglycerides (TGs) retention of a broad set of plant seed oils with isomeric conjugated octadecatrienoic acids (CLnA) by reversed-phase HPLC for "propanol-2-acetonitrile" mobile phases and Kromasil 100-5C18 stationary phase with diode array detection (DAD) and mass spectrometric (MS) detection. The subjects of investigation were TGs of seed oils: Calendula officinalis, Catalpa ovata, Jacaranda mimosifolia, Centranthus ruber, Momordica charantia, Trichosanthes anguina, Punica granatum, Thladiantha dubia, Valeriana officinalis, and Vernicia montana. It was found that a sequence of elution of TGs of the same types is the same without any inversions for full range of mobile phase compositions: punicic (C18:3 9Z11E13Z ) < jacaric (C18:3 8Z10E12Z ) < catalpic (C18:3 9E11E13Z ) < α-eleostearic (C18:3 9Z11E13E ) < calendic (C18:3 8E10E12Z ) < β-eleostearic (C18:3 9E11E13E ) < all-E calendic (C18:3 8E10E12E ) acids. TGs and fatty acid compositions were calculated for all oil samples. Regularities of solute retentions as a function of isomeric conjugated octadecatrienoic acid moiety structure are discussed. Thus, it was proven that it is possible to differentiate TGs of complex composition with moieties of all natural CLnA by retention control accomplished by electronic spectra comparison, even though there are only three types of electronic-vibration spectra for seven isomeric CLnA.

Determination of triacylglycerols and fatty acid composition ofChilopsis linearisseed oil by reverse-phase high-performance liquid chromatography

“…Thus, first of all, octadecatrienoic acid was proved to be a catalpic one. Then the increment for the replacement of linoleic with (9-trans,12-trans)-octadeca-9,12-dienoic acid substituents, found for catalpa seed oil TAGs [14], coincides with the increment ∆ (L→ Y) being the sum of two consecutive increments ∆(L → X) and ∆(X → Y) for Chilopsis linearis oil TAG. Thus, acid Y is the (9-trans,12-trans)-octadeca-9,12-dienoic acid substituent.…”

“…To determine the specific TAGs of Chilopsis linearis seed oil, chromatograms were registered at two wavelengths with subsequent comparison with the chromatogram of the catalpa seed oil. The composition of the latter oil had been determined by us earlier [14].…”

<i>Thladiantha</i> Seed Oils - New Source of Conjugated Fatty Acids: Characterization of Triacylglycerols and Fatty Acids

“…In our preliminary study 17 , we reported that the molar fraction of punicic acid of Thladiantha dubia seed oil slightly exceeds 35 . In the present work, composition of 15 TAGs that are listed in Fig.…”

“…The spectra of Thladiantha seed oils Fig. 1 is characterized by the absorption maxima at 263, 272 and 283 nm, being characteristic to that of conjugated trienoic compound 17 .…”

Rare fatty acids and lipids in plant oilseeds: occurrence and bioactivity

“…In addition, the two positional isomers trans,trans,cis-8,10,12-octadecatrienoic acid (calendic acid) and cis, trans,cis-8,10,12-octadecatrienoic acid (jacaric acid) (Fig. 1) have been identified in some Calendula and Jacaranda species (Chisholm and Hopkins 1965;Dulf et al 2013;Nguyen et al 2017).…”