Characterization of hydrophobic sol-gel materials containing entrapped lipases
Characterization of hydrophobic sol-gel materials containing entrapped lipases
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DOI：
10.1007/bf00401881
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发表时间：
1996-01-01
影响因子：
2.5
通讯作者：
Tesche, B
中科院分区：
文献类型：
--
作者：
Reetz, MT;Zonta, A;Tesche, B
将脂肪酶包埋在 RSi(OCH3)(3) 或 RSi(OCH3)(3) 和 Si(OCH3)(4) 的混合物的疏水性溶胶-凝胶材料中，产生的异质生物催化剂具有显着增强的酶活性（通过异辛烷中的正辛醇对月桂酸进行酯化来测量）。这些材料已通过固态核磁共振研究进行了表征，揭示了交联程度。结果表明，该参数通常与相对酶活性不相关。同样，比表面积或孔径似乎并不是确定含脂肪酶的混合凝胶和从 Si(OCH3)(4) 获得的相应 SiO2 凝胶的相对酶活性的决定性因素。扫描电子显微镜研究（SEM）表明，混合凝胶都具有相似的形态。在这些研究的基础上，提出了一个模型，根据该模型，大部分脂肪酶被捕获在凝胶颗粒的表面附近，在那里它很容易被底物分子接近。
The entrapment of lipases in hydrophobic sol-gel materials of RSi(OCH3)(3) or mixtures of RSi(OCH3)(3) and Si(OCH3)(4) results in heterogeneous biocatalysts having dramatically enhanced enzyme activities as measured by the esterification of lauric acid by n-octanol in isooctane. These materials have been characterized by solid state NMR studies, revealing the degree of cross-linking. It is shown that this parameter generally does not correlate with relative enzyme activity. Likewise, the specific surface area or the pore size does not seem to be the decisive factor in determining the relative enzyme activities of the lipase-containing hybrid gels and the corresponding SiO2-gels obtained from Si(OCH3)(4). Scanning electron microscopic studies (SEM) show that the hybrid gels all have a similar morphology. On the basis of these studies a model is proposed according to which most of the lipase enzyme is entrapped near the surface of the gel particles, where it is readily accessible by substrate molecules.