Immobilization of Aspergillus niger lipase onto a novel macroporous acrylic resin: Stable and recyclable biocatalysis for deacidification of high-acid soy sauce residue oil

Abstract

Deacidification of high-acid soy sauce residue (SSR) oil is crucial to utilization of SSR oil. Aspergillus niger lipase (ANL) has been widely applied for such purpose while its immobilization still has large room for improvement. ANL was immobilized onto six different macroporous acrylic resins, accounting the effect of the different textural properties of resins on stability and their potential for application in enzymatic deacidification. The resin MARE with lower porosity, higher bulk density, and medium hydrophobicity, was chosen as the best carrier for the best thermostability and reusability. ANL-MARE is a promising catalyst than Novozym 40086, which not only exhibited higher deacidification activity and good thermostability, but also was continuously reused for 15 cycles and efficiently catalyzed from high-acid SSR oil into diacylglycerol-enriched oil. Therefore, immobilized ANL was a novel, low-cost and recyclable biocatalyst that could be used as a good alternative to higher-cost commercial lipases in industrial applications.