Chemo-enzymatic synthesis, in vitro antioxidant activities and positive effects on oil-in-water emulsion Stabilization of phenolic acid-esterified phosphatidylcholines.

The industrial application of phenolic acids (PAs) is significantly limited by their low solubility and poor bioavailability in lipid-rich systems. Lipophilization via esterification of PAs with lipid matrices offers a promising approach to address these challenges. In this study, an efficient lipase-chemical catalytic method was developed for synthesizing phenolic acid-esterified phosphatidylcholines (PA-EPCs) from PAs and phosphatidylcholine (PC). Three derivatives-caffeic acid-esterified phosphatidylcholines (CA-EPC), ferulic acid-esterified phosphatidylcholines (FA-EPC), and p-hydroxycinnamic acid-esterified phosphatidylcholines (p-HCA-EPC)-were successfully obtained with isolated yields of 67.5 %, 84.5 %, and 85.3 %, respectively. Their structures were confirmed by 1H/13C NMR and ESI-MS analyses. Compared with unmodified PC, PA-EPCs, especially CA-EPC, showed significantly enhanced in vitro antioxidant activity, as demonstrated by assays of lipid peroxide value, DPPH/ABTS radical scavenging capacity, and ferric reducing antioxidant power (FRAP). Due to the incorporation of PC into PAs, PA-EPCs exhibited enhanced lipophilicity, which significantly improved the stability of oil-in-water (O/W) emulsions. This improvement was evidenced by higher emulsifying activity indices, smaller droplet sizes, more homogeneous distribution, and a slower increase in thiobarbituric acid reactive substances (TBARs) over time. Collectively, these findings indicate that PA-EPCs possess remarkable potential as effective antioxidants and emulsifiers in food, cosmetic, and pharmaceutical industries.