Synthesis of reusable lipases by immobilization on hexagonal mesoporous silica and encapsulation in calcium alginate : Transesterification in non-aqueous medium

摘要: Abstract Hexagonal mesoporous silica (HMS) was used for pre-immobilization of Candida antarctica lipase B (CAL B) and the effect calcium alginate encapsulation studied. Pseudomonas cepacia (PSL), rugosa (CRL) porcine pancreatic (PPL) were also studied, amongst which CAL found to be most active transesterification reaction. All lipases employed as biocatalysts in four different physical forms, such unsupported, immobilized on HMS, encapsulated (CA) pre-immobilized HMS using CA. Pre-immobilization hexagonal carried out by simple adsorption with an immobilization yield 62% maximum loading enzyme 100 mg per gram support. The recovered activity retained support 26%. when beads yields a highly reusable biocatalyst no leaching even after fourth reuse. This novel way preparation overcomes problem from avoiding direct shear involved within stirred reactor. activities all forms evaluated p-chlorobenzyl alcohol vinyl acetate give at 30 °C. A conversion 68% 100% selectivity obtained 30 °C 120 min, being CA B/HMS/Encap) equimolar concentrations reactants 1,4-dioxane solvent. B/HMS/Encap showed excellent reusability decrease only 4% overall reaction