两种微球载体固定化脂肪酶的研究

发布时间：2018-04-19 00:08

本文选题：脂肪酶 + 微球　；参考：《河北大学》2014年硕士论文

【摘要】：脂肪酶在实际应用中的催化能力具有高效性，在反应过程中副反应和副产物比非生物催化剂少，且在较温和的环境下就能进行催化反应，因此，被广泛地应用到了工业化生产中。然而其稳定性差和难回收等缺点限制了其在生产中的应用，为了克服这些缺点，将游离酶通过物理吸附法、包埋法或共价结合法进行固定化研究。本文分为两部分。第一部分，首先以苯乙烯（St）和丙烯酸（AA）为单体，通过乳液聚合法，制备出具有羧基功能基团的P(St-AA)磁性微球，再以所制备的磁性微球为载体，通过共价结合的方法对Candida rugosa lipase进行固定化，，考察了不同长度的间隔臂链（乙二胺和PEG400/800/4000）修饰到磁性微球上对克服空间位阻的影响。结果表明，当使用PEG800/4000作为间隔臂链时，可以有效地克服空间位阻。结果还表明，过高的酶载量会产生空间位阻而影响酶的活性。并进一步研究了PEG800在磁性微球上的修饰量对固定化酶活性的影响。第二部分，以乙酸乙烯酯（VAC）、丙烯酰胺（AM）为单体，通过悬浮聚合法制备了P(VAC-AM)高分子微球，并以此高分子微球为载体，通过环氧氯丙烷共价结合Candidarugosa lipase，考察了高分子微球环氧基的修饰条件和脂肪酶的固定化条件。由结果可以看出，转速为600r/min，环氧氯丙烷的用量为3mL，酶的用量为5mg，并且固定化时间为2h时，固定化酶的活性回收率达到最大为48%。
[Abstract]:The catalytic ability of lipase in practical application is effective, the side reaction in the process and the by-product of non biological catalyst, and can be carried out under mild reaction conditions, therefore, it is widely applied in industrial production. However, its poor stability and difficult recovery in their application is limited. In the production, in order to overcome these shortcomings, the free enzyme by physical adsorption or covalent binding method of embedding immobilization.
This paper is divided into two parts. The first part, firstly, using styrene (St) and acrylic acid (AA) as the monomer by emulsion polymerization, prepared with carboxyl functional groups of P (St-AA) magnetic microspheres, magnetic microspheres with the prepared as the carrier, by covalent coupling method for immobilization Candida rugosa lipase, investigated the spacer chains of different lengths (ethylenediamine and PEG400/800/4000) modified magnetic microspheres to overcome the steric effects. The results show that when using PEG800/4000 as the spacer chain, can effectively overcome the steric hindrance. The results also showed that high enzyme loading produces influence enzyme the activity of steric hindrance. And further study the effects of modified PEG800 on the magnetic microspheres on the activity of immobilized enzyme.
The second part, with vinyl acetate (VAC), acrylamide (AM) monomers were prepared by suspension polymerization of P (VAC-AM) microspheres, and the polymer microspheres by epoxy chloropropane covalently bound Candidarugosa lipase immobilized conditions investigated polymer microspheres epoxy modification conditions and lipase. The test results show that the speed of 600r/min, epichlorohydrin dosage is 3mL, the dosage of enzyme is 5mg, and the immobilization time of 2h, the activity recovery rate of immobilized enzyme reached 48%.

【学位授予单位】：河北大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：R917

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