Preparation of vacuum-assisted conjugated linoleic acid phospholipids under nitrogen: Mechanism of acyl migration of lysophospholipids.

[Display omitted] • Sn-1-lysophosphatidylcholine underwent acyl migration due to structural instability. • Acyl migration rate was higher under acidic or alkaline conditions. • Nitrogen/vacuum increased yield of conjugated linoleic acid lysophosphatidylcholine. • The maximum yield was achieved when the vacuum pressure was 13.3 KPa. Sn -Glycerol-3 - phosphatidylcholine (GPC) was prepared by hydrolysis of phosphatidylcholine (PC) catalyzed by phospholipase A 1 (PLA 1). Nitrogen flow assisted the esterification of conjugated linoleic acid (CLA) and GPC to produce conjugated linoleic acid lysophosphatidylcholine (LPC − CLA). The effects of different reaction conditions on the PC conversion and acyl migration rates were investigated, and the acyl migration mechanism under acidic and alkaline conditions was studied. In addition, the optimum conditions for the esterification of CLA and GPC were selected. The optimal condition for the hydrolysis of PC was an enzyme loading of 5 %, pH of 5, reaction temperature of 50 ℃, and reaction time of 3 h. The results also showed that the maximum esterification rate reached 82.37 % at an enzyme loading of 15 %, CLA/GPC molar ratio of 50:1, and vacuum pressure of 13.3 kPa. This study not only improved the bioavailability of PC but also effectively increased the content of LPC − CLA. [ABSTRACT FROM AUTHOR]