Lipase‐catalyzed transesterification of virgin and refined hemp seed oil with ferulic acid ethyl ester

Abstract

The transesterification of ethyl ferulate (EF) and unrefined, virgin, cold pressed hemp seed oil (HOV) and refined, bleached, deodorized cold pressed hemp seed oil (HOR) using a commercial lipase, Novozym 435 (Candida antarctica B lipase immobilized on an acrylic resin), was examined in 150‐mL, shaken, batch reactions at 60°C for 2 weeks. The reactions produced feruloylated hemp seed oils, FHOV and FHOR, respectively, and the reactions were monitored to determine the difference between virgin and refined hemp seed oil on the transesterifications. The FHOV and FHOR reactions both reached EF conversion equilibrium of 58% after ca. 168 h. Ultraviolet (UV) absorbing and antioxidant capacity of the FHOV and FHOR were determined. Both FHOV and FHOR (50 μM in ethanol) were excellent UVA II absorbers, λmax 322 nm, and exhibited absorption into the UVB. The DDPH* radical (200 μM) scavenging of the FHOV and FHOR (0.25–2.5 mM) were both shown to be rapid antioxidants (50% DDPH* radical scavenged in <5 min) at 1.0 and 2.5 mM suggesting that inherent components contained in the HOV did not adversely affect enzyme activity relative to transesterification using HOR. Overall, using less expensive, unrefined, virgin hemp seed oil versus more expensive, refined hemp seed oil did not appreciably affect the enzyme kinetics of the transesterification reactions nor the UV absorbing and antioxidant efficacy of the resultant feruloylated hemp seed oils, making FHOV a less expensively produced feruloylated hemp seed oil for cosmetic and personal care applications.