Construction of biocatalytic colloidosome using lipase-containing dendritic mesoporous silica nanospheres for enhanced enzyme catalysis

The synthesis of silica-based colloidosome with a magnetic solid core via Pickering emulsification and its use as an immobilized enzyme system is described in this work. Lipase B from Candida antarctica (CALB) was physically adsorbed on the material to form the immobilized enzyme (LP@colloidosome) and the enzyme loading was 166.3   mg/g support . The specific hydrolytic activity of LP@colloidosome was 209.6   U/g support and its immobilization yield was 22.08%. The stability test indicated that LP@colloidosome can retain 49% of original activity after incubation at 50   °C for 6   h and 105.6% of original activity after incubation in t -butanol for 96   h, while the free lipase lost most the initial activity under the same condition. These findings showed that LP@colloidosome had the enhanced thermal stability and tolerance in organic solvents. Meanwhile, LP@colloidosome can be easily recovered by magnet due to the addition of modified Fe 3 O 4 nanoparticles in the solid core. LP@colloidosome was successfully used to catalyze the esterification of fatty acids and alcohols with different length in organic solvent. The yields of the corresponding esters that catalyzed by LP@colloidosome were significantly higher than those catalyzed by free lipase. Additionally, the versatility of LP@colloidosome was also verified in the synthesis of glycerol carbonate through transesterification. The results indicated that biosynthesis of glycerol carbonate from glycerol using the LP@colloidosome (6.1   wt%) as catalyst afforded 85.20% of conversion rate at 60   °C. This work offers insight into the design of colloidosome for efficient immobilization of lipase as well as improvement of the lipase’s properties.