Studies on the enzymatic synthesis and free radical scavenging ability of phenolic acid glycerols

The potentially wide application of Phenolic acids (PAs) in industries was severely limited by their inadequate solubility and stability in polar/non-polar media. To overcome these limits, studies on the enzymatic esterification of PAs with glycerol were carried out to reach a yield of 95% of phenolic acid glycerols (PAGs) under the following reaction conditions: 1:150 molar ratio of caffeic acid (CA) to glycerol; 25% Lipozyme 435 relative to the weight of total substrates; temperature 80 C, 500 rpm; 86.7 kPa and reaction time 10 h. Three resulting PAGs including caffeoyl glycerol (CG), feruloyl glycerol (FG) and p -hydroxycinnamoyl glycerol ( p -HCG) were confirmed by MS, H NMR and C NMR. Among them, CG showed a comparative free radical scavenging ability to CA, indicating its potential use as a water-soluble antioxidant alternative to CA for food and cosmetic applications.