Heart‐Cut Two‐Dimensional Countercurrent Chromatography for the Isolation of a Furan Fatty Acid Triacylglycerol from Latex Gloves and Identification of Further Lipid Compounds

Abstract

Hevea brasiliensis latex from specific genotypes such as RRIM501 or PB235 is one of the richest natural sources of furan fatty acid 9-(3-methyl-5-pentylfuran-2-yl)nonanoic acid (9M5), which is mainly present in the form of triacylglycerols. In this study, we successfully isolated a triacylglycerol esterified with three 9M5 molecules (tri-9M5) with a purity of 97% from the lipid extract of latex gloves by means of countercurrent chromatography (CCC). The gas chromatography with a mass spectrometry (GC/MS) spectrum of tri-9M5 not only featured the diagnostic fragment ion [M-RCOO] + of triacylglycerols but also a fragment ion shifted by 16 Da to higher mass which corresponded with [M-RCO] + . [M-RCO] + was only detected in triacylglycerols substituted with at least one furan fatty acid. Additionally, five γ-tocotrienyl fatty acid esters (γ-T 3 -FA esters), namely, γ-T 3 -16:0, γ-T 3 -18:0, γ-T 3 -18:1n-9, γ-T 3 -18:2n-6 and γ-T 3 -20:0, were detected in the sample. Contributions of γ-T 3 -FA esters with 18:1n-9 and 18:2n-6 which co-eluted in GC/MS could be calculated after mathematical correction for contributions of the 13 C 2 isotope peak of γ-T 3 -18:2n-6 to γ-T 3 -18:1n-9. This was necessary for quantitation of these two γ-T 3 -FA esters. Improved separation of the γ-T 3 -FA esters could be achieved by the novel heart-cut recycling CCC mode (four cycles). Sterols detected in disposable latex gloves were β-sitosterol, Δ 5avenasterol, and stigmasterol along with small quantities of 24-methylene-cycloartenol and Δ 5 -citrostadienol.Keywords Triacylglycerol Á Countercurrent chromatography Á Hevea brasiliensis latex Á 9M5 Á Furan fatty acid Á Tocotrienyl fatty acid ester J Am Oil Chem Soc (2020) 97: 463-474. Fig. 1 (a) General structure of a triacylglycerol with R 1 , R 2 , and R 3 being acyl moieties and structure of (b) the characteristic GC/MS fragment ion [M-RCOO] + of triacylglycerols, (c) the [M-RCO] + fragment ion additionally found only in the presence of at least one furan fatty acid, and (d) the furan fatty acid 9M5. R 1,2,3 = fatty acid residue (one or more furan fatty acids). The structure with R 1, R 2, R 3 = 9M5 corresponds with tri-9M5 464J Am Oil Chem Soc J Am Oil Chem Soc (2020) 97: 463-474

LC-Orbitrap-HRMS method for analysis of traces of triacylglycerols featuring furan fatty acids

“…Beyond that, the characteristic and abundant GC/MS fragment ions of FuFA-ME (e.g., m / z 165 (base peak)) are also present in the LC/MS spectra of FuFA-containing TAGs (FuFA-TAGs) [ 26 ].…”

Full Characterization of the UV Hydrodebromination Products of the Current-Use Brominated Flame Retardants Hexabromobenzene, Pentabromotoluene, and Pentabromoethylbenzene

“…and 0.1 μm d f , from Restek, Bad Homburg, Germany). Operating conditions were set as described in other studies. , Measurements were performed in full-scan mode ( m / z 50–550).…”

“…Operating conditions were set as described in other studies. 31,32 Measurements were performed in full-scan mode (m/z 50−550). 1 H NMR.…”

Enzymatische Synthese von Triacylglyceriden mit Furanfettsäuren (FuFAs) unter Einsatz der rekombinanten Lipase von Candida antarctica

“…Daher sollten in dieser Studie erstmals FuFA-haltige Triacylglyceride synthetisiert werden. Dazu wurde zunächst die FuFA 9-(3-Methyl-5-pentylfuran-2-yl)-nonansäure (9M5) und deren Triacylglycerid "tri9M5" aus Latex isoliert [6]. Bei Latex (Kautschuk) handelt es sich um die einzige natürliche Quelle mit hohem Anteil einer FuFA.…”

“…Zur enzymatischen Acidolyse wurde die immobilisierte Lipase von Candida antarctica, welche rekombinant in Aspergillus niger exprimiert wurde und kommerziell verfügbar ist, eingesetzt. Nach Inkubation von Triacylglyceriden mit drei identischen Fettsäuren, dem Enzym und freier 9M5 in n-Hexan (Schüttelbad, 22 h, 45 °C) wurden die Reaktionsprodukte nach Abfiltrieren des Enzyms und Aufarbeitung der Proben mittels GC/MS unter Berücksichtigung charakteristischer Fragmentionen untersucht [6]. Es ergab sich, dass das Enzym in der Lage war, FuFAs in ein bestehendes Triacylglycerid einzubauen, wobei die Positionen aufgrund selektiver Ionen eindeutig ermittelt werden konnten.…”