Green efficient approach for the synthesis of feruloylated acylglycerols using amberlyst-35 as a novel catalyst: optimization and function evaluation

Abstract

Ferulic acid (FA) is a natural phenolic compound with antioxidant and UV-absorbing properties. However, its poor lipophilicity limits its application in lipid-based systems. In this study, a sustainable and efficient approach was proposed for synthesizing lipophilic feruloylated acylglycerols (FAGs). The reaction was carried out through the esterification of FA with glycerides, catalyzed by the heterogeneous cation exchange resin Amberlyst-35. A range of reaction variables, including pressure, catalyst type, acyl acceptor, temperature, catalyst dosage, and substrate molar ratio, were systematically investigated. The results showed that A-35 and glycerol monostearate (GMS) were identified as the optimal catalyst and acyl acceptor, respectively. Response surface methodology was used to optimize the process. Under mild vacuum conditions (105 °C, 18 % catalyst dosage, FA:GMS = 1:7, reaction time 16 h), the FAGs yield could reach as high as 95.01 %. Kinetic analysis indicated Arrhenius-type behavior with an activation energy of 58.96 kJ/mol. The obtained FAGs exhibited strong UV absorption (λ_max = 328 nm) and maintained more than 67 % photostability after 96 h of irradiation, which demonstrated its potential as a natural multifunctional additive. This study presents a practical method to produce lipophilic ferulic acid derivatives, helping develop sustainable ingredients for food and cosmetics.