Exploring the Automatic Oxidation Process of Antarctic Krill Oil Using Traditional Methods Coupled with Uplc-Esi-Ms/Ms Technology

Abstract

The rules and molecular mechanisms of lipids changes during automatic oxidation of Antarctic krill oil (AKO) were investigated using traditional methods coupled with untargeted lipidomics in this study. A total of 2967 lipids (6 lipid categories and 41 lipid subclasses) were identified. The oxidation process of AKO was divided into three stages, rapid oxidation, co-oxidation, and deep oxidation stage. The rapid oxidative stage was dominated by astaxanthin and glycerophospholipids degradation, with significant decreases in the abundance of lysophosphatidylethanolamine (LPE, 20:5) and LPE (22:6). Co-oxidation of glycerophospholipids and glycerolipids subsequently occurred, with significant decrease of phosphatidylethanolamine (PE), phosphatidylglycerol, phosphatidylinositol, cardiolipin and triglycerides. Especially, the abundance of LPE (20:5), LPE (22:6), PE (20:5/22:6) and PE (20:5/20:5) were significantly decreased. The percentage of lipids containing only FA with the number of double bonds ＜2 in the significantly increased abundance lipids was as high as 83.87% during this period.

Keywords: Antarctic krill oil, Lipid oxidation, Free radical, Untargeted lipidomics, Astaxanthin, Molecular mechanisms