微乳液中脂肪酶和含明胶的微乳液凝胶中固定化脂肪酶的催化特性

在双2-乙基己基琥珀酸酯磺酸钠(AOT)油包水微乳液中Calytical脂肪酶催化月桂酸和戊醇的酯化反应动力学研究表明,反应符合乒乓(BiBi)机制.表观速率常数k_m酸=0.13518mol/L,k_m醇=0.22423mol/L,最大反应速度v_max=1.3873×10^-5mol/(L·min·mg).将该脂肪酶固定于含明胶的微乳液凝胶(MBGs)中,制得固定化脂肪酶,含酶MBGs在非极性溶剂中可作为固相催化剂,并研究了其在辛烷中催化酯化的性能.所制得的含酶MBGs物理稳定性好,重复利用10次以上,其转化率仍达初始转化率的90%.

Catalytic Behavior of Lipase in W/O Microemulsion and Immobilized Lipase in Gelatin Microemulsion-Based Organogels

The kinetics of the esterification of lauric acid and 1 pentanol catalyzed by Calytical (CL) lipase, was studied in water/bis (2-ethylhexyl)sulfosuccinate sodium(AOT)/isooctane microemulsions. The kinetics studies showed that the reaction followed a Ping Pong Bi-Bi mechanism. The values of all apparent kinetic parameters were determined. The apparent kinetic parameters of the reaction were found to be k_m(lauric acid)=013518 mol/L, k_m(1 pentanol)=022423 mol/Land v_max=13873×10^-5 mol/(L·min·mg). Lipase has also been immobilized in gelatin containing AOT-microemulsion based organogels(MBGs). These lipase containing MBGs prove to be a novel solid-phase catalysts for the use in apolar organic solvents and have a good physical stability. These lipase containing MBGs retained its higher activity after 10 runs esterification reactions.