Interdisciplinary Nanoscience Center (iNANO), Aarhus University, Aarhus C DK-8000, Denmark.
Langmuir. 2012 Apr 10;28(14):6157-62. doi: 10.1021/la300469s. Epub 2012 Mar 21.
Use of biocatalysis for industrial synthetic chemistry is on the verge of significant growth. Enzyme immobilization as an effective strategy for improving the enzyme activity has emerged from developments especially in nanoscience and nanotechnology. Here, lipase from Burkholderia cepacia (LBC), as an example of the luxuriant enzymes, was successfully encapsulated in polycaprolactone (PCL) nanofibers, proven by X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM). Evaluated in both organic and aqueous medium, the activation factor of the encapsulated enzymes in the hydrolysis reaction was generally higher than that in the transesterification reaction. Enhanced catalytic activities were found when 5-20 w/w % of LBC was loaded. The effect of different solvents pretreatment on the activity of immobilized LBC was also investigated. The highest activation factor was found up to 14 for the sample containing acetone-treated LBC/PCL (10 w/w %). The encapsulated lipase reserved 50% of its original activity after the 10th run in the transesterification reaction in hexane medium. The mechanism of activation of lipase catalytic ability based on active PCL nanofiberous matrix is proposed.
生物催化在工业合成化学中的应用正处于显著增长的边缘。酶固定化作为提高酶活性的有效策略，特别是在纳米科学和纳米技术的发展中已经出现。在这里，以洋葱伯克霍尔德氏菌脂肪酶（LBC）为例，它是一种丰富的酶，成功地被包裹在聚己内酯（PCL）纳米纤维中，这一点通过 X 射线光电子能谱（XPS）和原子力显微镜（AFM）得到了证明。在有机和水介质中进行评估时，包裹酶在水解反应中的活性因子通常高于在酯交换反应中的活性因子。当负载 5-20 w/w %的 LBC 时，发现了增强的催化活性。还研究了不同溶剂预处理对固定化 LBC 活性的影响。在含有丙酮处理的 LBC/PCL（10 w/w %）的样品中，发现最高的活性因子高达 14。在正己烷介质中的酯交换反应中，第 10 次循环后，包裹脂肪酶保留了其原始活性的 50%。提出了基于活性 PCL 纳米纤维基质的脂肪酶催化能力的激活机制。
