In the present study, the formation and further reactions of intact steryl ester hydroperoxides were followed in a tripalmitin matrix maintained at 100°C. The effects of the acyl moiety and its unsaturation degree, and of the sterol structure were investigated. Intact steryl ester hydroperoxides were isolated from the lipid matrix by a developed solid-phase extraction (SPE) method and were determined by HPLC-ELSD. Further reactions of hydroperoxides were followed by determining secondary oxidation products of sterol by GC-FID/MS and oligomers by HPSEC-RI. The oxidation of sterol decreased when its solubility in the lipid medium was increased by introduction of acyl moiety. Increased unsaturation of the acyl or steryl moiety of steryl ester shortened the induction period and increased the oxidation of both steryl and acyl moieties. Thus, by changing the chemical and physical properties of sterols, their oxidation may be greatly affected.
Download full-text PDF |
Source |
|---|---|
| http://dx.doi.org/10.1016/j.foodchem.2012.04.007 | DOI Listing |
Publication Analysis
Top Keywords
Similar Publications
Differential impact of impaired steryl ester biosynthesis on the metabolome of tomato fruits and seeds.
Physiol Plant
December 2024
Plant Synthetic Biology and Metabolic Engineering Program, Centre for Research in Agricultural Genomics (CRAG), CSIC-IRTA-UAB-UB, Cerdanyola, Barcelona, Spain.
Steryl esters (SE) are a storage pool of sterols that accumulates in cytoplasmic lipid droplets and helps to maintain plasma membrane sterol homeostasis throughout plant growth and development. Ester formation in plant SE is catalyzed by phospholipid:sterol acyltransferase (PSAT) and acyl-CoA:sterol acyltransferase (ASAT), which transfer long-chain fatty acid groups to free sterols from phospholipids and acyl-CoA, respectively. Comparative mass spectrometry-based metabolomic analysis between ripe fruits and seeds of a tomato (Solanum lycopersicum cv Micro-Tom) mutant lacking functional PSAT and ASAT enzymes (slasat1xslpsat1) shows that disruption of SE biosynthesis has a differential impact on the metabolome of these organs, including changes in the composition of free and glycosylated sterols.
View Article and Find Full Text PDFA Procedure for Solid-Phase Extractions Using Metal-Oxide-Coated Silica Column in Lipidomics.
Anal Chem
October 2024
Department of Biotechnology and Life Science, Tokyo University of Agriculture and Technology, 2-24-16 Naka-cho, Koganei, Tokyo 184-8588, Japan.
Lipid enrichment is indispensable for enhancing the coverage of targeted molecules in mass spectrometry (MS)-based lipidomics studies. In this study, we developed a simple stepwise fractionation method using a titanium- and zirconium-dioxide-coated solid-phase extraction (SPE) silica column that separates neutral lipids, phospholipids, and other lipids, including fatty acids (FAs) and glycolipids. Chloroform was used to dissolve the lipids, and neutral lipids, including steryl esters, diacylglycerols, and triacylglycerols, were collected in the loading fraction.
View Article and Find Full Text PDFVirgin Olive oil Authenticity Assays in a Single Run Using Two-Dimensional Liquid Chromatography-High Resolution Mass Spectrometry.
Anal Chem
October 2024
Analytical Chemistry Research Group, Department of Physical and Analytical Chemistry, University of Jaén, Campus Las Lagunillas, 23071 Jaén, Spain.
Sterols and triterpenic alcohol analyses are one of the officially established parameters for assessing the authenticity of virgin olive oil (VOO). Most of the applications described for sterol analysis, including the official method, only allow the determination of the total sterol content but not its distribution in free or esterified form. This work proposes a two-dimensional liquid chromatography/high-resolution mass spectrometry (2D-LC-HRMS) method for the simultaneous analysis of triterpenic alcohols, free sterols and steryl esters.
View Article and Find Full Text PDFLipid droplets degradation mechanisms from microalgae to mammals, a comparative overview.
Biochimie
December 2024
Laboratoire de Physiologie Cellulaire et Végétale, Université Grenoble Alpes, Institut National de Recherche pour l'Agriculture, l'Alimentation et l'Environnement, Centre National de la Recherche Scientifique, Commissariat à l'Energie Atomique et Aux Energies Alternatives, IRIG, CEA-Grenoble, 17 Rue des Martyrs, 38000, Grenoble, France. Electronic address:
Lipid droplets (LDs) are organelles composed of a hydrophobic core (mostly triacylglycerols and steryl esters) delineated by a lipid monolayer and found throughout the tree of life. LDs were seen for a long time as simple energy storage organelles but recent works highlighted their versatile roles in several fundamental cellular processes, particularly during stress response. LDs biogenesis occurs in the ER and their number and size can be dynamically regulated depending on their function, e.
View Article and Find Full Text PDFRoles of plastoglobules and lipid droplets in leaf neutral lipid accumulation during senescence and nitrogen deprivation.
J Exp Bot
October 2024
Université Bordeaux, CNRS, Laboratoire de Biogenèse Membranaire, UMR 5200, F-33140 Villenave d'Ornon, France.
Upon abiotic stress or senescence, the size and/or abundance of plastid-localized plastoglobules and cytosolic lipid droplets, both compartments devoted to neutral lipid storage, increase in leaves. Meanwhile, plant lipid metabolism is also perturbed, notably with the degradation of thylakoidal monogalactosyldiacylglycerol (MGDG) and the accumulation of neutral lipids. Although these mechanisms are probably linked, they have never been jointly studied, and the respective roles of plastoglobules and lipid droplets in the plant response to stress are totally unknown.
View Article and Find Full Text PDFWant AI Summaries of new PubMed Abstracts delivered to your In-box?
Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!