Carbon Nanoparticle-Stabilized Pickering Emulsion as a Sustainable and High-Performance Interfacial Catalysis Platform for Enzymatic Esterification/Transesterification

A sustainable and efficient reaction system for enzymatic oil modification is imperative for the food industry. Given the interfacial activation effect of lipase, the sufficient oil–water interface is vital for excellent catalytic activity of lipase. In the present study, a Pickering emulsion reaction system was prepared through directly using reactants as the oil phase and stabilized by mesoporous carbon spheres (MCS) after immobilization of lipase AYS (Candida rugosa, lipase@MCS). Lipase@MCS worked as both the emulsifier and catalyst. Each droplet in the Pickering emulsion was regarded as a microreactor with the reactants in the oil phase, and the removal of the product H2O “pushed” the reaction forward. Taking advantage of the adequate oil–water interface for “lid” opening of lipase and rapid mass transfer in MCS, the Pickering emulsion exhibited excellent enzymatic activity toward phytosterol esterification and transesterification, achieving 95.0% conversion after 1.5 h and catalytic efficiency (CE) o...