Green synthesis of polydopamine functionalized magnetic mesoporous biochar for lipase immobilization and its application in interesterification for novel structured lipids production

In this study, the polydopamine functionalized magnetic mesoporous biochar (MPCB-DA) was prepared for immobilization of Bacillus licheniformis lipase via covalent immobilization. Under optimized immobilization conditions, the maximum immobilization yield, efficiency and immobilized lipase amount were found to be 45%, 54% and 36.9 mg/g, respectively. The immobilized lipase, MPCB-DA-Lipase showed good thermal stability and alkali resistance. The MPCB-DA-Lipase retained 56% initial activity after 10 reuse cycles, with more than 85% relative activity after 70 days' storage at 4 or 25 °C. The MPCB-DA-Lipase was efficiently applied in the interesterification of Cinnamomum camphora seed kernel oil and perilla seed oil, with maximum interesterification efficiency of 46%. The produced structured lipids belong to the S2U and U2S triacylglycerols, a novel medium-and long-chain triacylglycerol. These results demonstrated that the MPCB-DA-Lipase may be used as an efficient biocatalyst in lipid processing applications of food industries.