摘要
以甲基三甲氧基硅烷(MTMS)、乙烯基三甲氧基硅烷(VTMOS)、乙烯基三乙氧基(VTEOS)、辛基三甲氧基硅烷(OTMOS)和四甲氧基硅烷(TMOS)为前趋体制备4种不同的固定化脂肪酶,并系统考察了烷基侧链对sol-gel固定化酶胶体结构和酶活性的影响。结果表明,随着烷基侧链的增长和数目的增加,固定化酶活力均逐渐增加,固定化脂肪酶颗粒平均孔径逐渐增大,孔体积逐渐增加,对底物的传质阻力逐渐降低;同时颗粒逐渐由球形变成不定形或团块状结构。脂肪酶活性的增加不仅来源于疏水性烷基侧链引起的脂肪酶的界面激活效应,同时固定化颗粒结构的改变了增加了底物和酶分子的结合,提高了固定化酶的表观活性。
Four silane precursors, methyltrimethoxysilane （MTMS）, vinyltrimethoxysilane （VTMOS）, vinyltrimethoxysilane （VTEOS）, and n-octyltrimethoxysilane （OTMOS）, are used as precursors to prepare various kinds of immobilized lipases, and the correlation between the alkyl of silane and the activity of the gel-encapsulated lipases are studied. The results show that with the increase of the chain length and the number of alkyl groups, the total activity of the immobilized lipase, its average pore size, and pore volume are increasing, while the mass transfer resistance of substrate is going down gradually. Meanwhile, the particles become amorphous or clumpy from sphere. The improvement of the activity may be caused by the opener conformation of the lipase triggered by the hydrophobic octyl groups and texture change of the gel matrices. And the change of particle morphology may increase the substrates concentration close to the active sites of the enzyme that increases the apparent activity of them.
出处
《现代化工》
CAS
CSCD
北大核心
2009年第11期56-58,60,共4页
Modern Chemical Industry
基金
国家"863"项目(2007AA05Z417)
关键词
脂肪酶
有机硅烷
界面激活
表面积
孔径
lipase
silane
interfacial activation
surface area
pore diameter
