Department of Bio- and Chemical Engineering, TU Dortmund, Emil-Figge-Strasse 66, Dortmund, Germany.
Biotechnol Bioeng. 2013 Sep;110(9):2333-42. doi: 10.1002/bit.24906. Epub 2013 May 14.
The use of enzymes as biocatalysts in organic media is an important issue in modern white biotechnology. However, their low activity and stability in those media often limits their full-scale application. Amphiphilic polymer conetworks (APCNs) have been shown to greatly activate entrapped enzymes in organic solvents. Since these nanostructured materials are not porous, the bioactivity of the conetworks is strongly limited by diffusion of substrate and product. The present manuscript describes two different APCNs as nanostructured microparticles, which showed greatly increased activities of entrapped enzymes compared to those of the already activating membranes and larger particles. We demonstrated this on the example of APCN particles based on PHEA-l-PDMS loaded with α-Chymotrypsin, which resulted in an up to 28,000-fold higher activity of the enzyme compared to the enzyme powder. Furthermore, lipase from Rhizomucor miehei entrapped in particles based on PHEA-l-PEtOx was tested in n-heptane, chloroform, and substrate. Specific activities in smaller particles were 10- to 100-fold higher in comparison to the native enzyme. The carrier activity of PHEA-l-PEtOx microparticles was tenfold higher with some 25-50-fold lower enzyme content compared to a commercial product.
在有机介质中使用酶作为生物催化剂是现代白色生物技术中的一个重要问题。然而，它们在这些介质中的低活性和稳定性常常限制了它们的全面应用。两亲聚合物互穿网络 (APCNs) 已被证明可以大大激活有机溶剂中的包埋酶。由于这些纳米结构材料是非多孔的，所以网络的生物活性受到底物和产物扩散的强烈限制。本文描述了两种不同的作为纳米结构化微粒的 APCN，与已经具有激活作用的膜和较大颗粒相比，它们包埋的酶的活性大大提高。我们以基于 PHEA-l-PDMS 的负载α-糜蛋白酶的 APCN 颗粒为例证明了这一点，结果表明，与酶粉相比，该酶的活性提高了 28000 倍。此外，在正庚烷、氯仿和底物中测试了基于 PHEA-l-PEtOx 的颗粒中固定化的里氏木霉脂肪酶。与天然酶相比，较小颗粒中的比活性提高了 10-100 倍。与商业产品相比，PHEA-l-PEtOx 微粒的载体活性高 10 倍，而酶含量低 25-50 倍。
