乙酰胆碱酯酶固定化方法的研究

以戊二醛为交联剂,牛血清白蛋白(BSA)为保护剂,将乙酰胆碱酯酶(AchE)交联固定到商品载体上,制备固定化酶片。对影响酶固定化的重要因素进行了考察,获得了最佳固定化条件。实验结果表明,以孔径为0．45μm的硝酸纤维素滤膜作栽体,乙酰胆碱酯酶用量10U,5％(体积分数)戊二醛2μL,1％(质量分数)BSA10μL,配成70μL的酶溶液,3℃固定8h,可获得较好的固定化效果。不同批次制备的酶片,其活力值标准偏差为3.27％～5．03％,酶片在0．1mol／L pH8．5磷酸盐缓冲溶液中3℃下可保存60d。‘     

固定化猪肝酯酶法制备S-4-甲基哌啶酸的研究

S-4-甲基哌啶酸是重要的药物中间体,本文考察了海藻酸钠、壳聚糖等制备固定化猪肝酯酶的工艺稳定性,确定了最适酶浓度、底物浓度、温度和pH。壳聚糖法固定化猪肝酯酶选择性水解制备S-4-甲基-哌啶甲酸,de值高达99%,固定化酶重复利用率高,工艺稳定。     

乙酰胆碱酯酶分子生物学研究进展

乙酰胆碱酯酶是一种在神经传导中起关键作用的酶。它对有机磷农药十分敏感,可作为生物传感器监测环境中有机磷农药的含量。因此对乙酰胆碱酯酶的分子生物学研究是十分必要的。文章介绍了乙酰胆碱酯酶的分子形式、三维结构、基因结构,变构乙酰胆碱酯酶与抗药性的关系以及乙酰胆碱酯酶分子领域应用等方面的研究进展,并对乙酰胆碱酯酶的进一步研究提出了展望。     

乙酰胆碱酯酶在尼龙网上的固定化研究

以尼龙网为载体,分别用硫酸二甲酯和三乙基肟四氟化硼作烷基化试剂使尼龙网活化,然后将尼龙网浸入一定浓度的乙酰胆碱酯酶溶液中,置于4°C条件下进行固定化,获得了较好的固定化效果,酶膜活性分别达到4.2 U/cm2和11.1 U/cm2,固定化效率分别达到24.2%和64.1%,重现性好,稳定性好,5个月后活性无明显下降。     

固定化乙酰胆碱酯酶的制备及其在中药抑制剂筛选中的应用

采用固定化酶的方法从治疗阿尔茨海默病的常用中药中筛选出具有乙酰胆碱酯酶(acetylcholinesterase, AChE)抑制活性的品种。结果表明,AChE能较好的固定在修饰羧基的磁珠表面,在酶浓度8 mg/mL、固定时间4 h、缓冲液pH5.0、固定温度20℃的条件下,固定的AChE具有最佳的酶固载量及酶活性;将所合成的固定化酶与高效液相色谱-质谱(LC-MS/MS)技术相结合,成功筛选出石菖蒲、川芎、茯苓、当归等4味具有较好AChE抑制活性的药材。     

固定化植物酯酶的制备及应用

以麦草秸秆为原料,经环氧氯丙烷和乙二胺改性,戊二醛交联,制备了植物酯酶的固定化材料,研究了固定化植物酯酶的最优条件和固定化酶的酶学性质。结果表明,加酶量为20 m L/g(改性麦杆),固定化时间为6 h,温度为35℃,p H为7.0条件下,固定化效果最好,酶活回收率可达46%。固定化酶的p H稳定性、热稳定性和贮存稳定性都明显优于游离酶。固定化酶的米氏常数为41 mmol/L,固定化酶与底物的亲合力低于游离酶。建立了酶抑制反应的标准曲线和检测敌敌畏的方法,线性范围为1.0×10-4~6.25×10-4mg/L,检测下限为0.06μg/L。     

利用植物酯酶快速检测有机磷农药残留的研究进展

植物酯酶与动物乙酰胆碱酯酶一样可以有效地检测有机磷农药残留,介绍了利用植物酯酶快速检测有机磷农药残留的原理、酶源的选择、使用的优缺点以及存在的问题和解决的方法。     

新烟碱类杀虫剂的回顾和展望

到目前为止 ,世界杀虫剂市场 (2 0世纪 90年代初 >70亿美元 )主要由乙酰胆碱酯酶 (AChE)抑制剂统治。乙酰胆碱酯酶是昆虫中枢神经系统 (CNS)中最重要的酶之一 ,乙酰胆碱是重要的神经传递剂 ,而乙酰胆碱酯酶负责乙酰胆碱的降解作用。然而 ,乙酰胆碱酯酶抑制剂 ,如 :有机磷和氨基甲酸酯的市场份额从 1 987年的 71 %下降到 1 999年的 4 7%。AChE抑制剂与那些作用于压敏钠通道的杀虫剂 (尤其是拟除虫菊酯类杀虫剂 )构成了世界杀虫剂市场的 6 4% ,也就是说这两种作用机制的杀虫剂占世界杀虫剂市场的 2 / 3。烟碱乙酰胆碱受体 (nAChR)作为杀…     

沙棘叶提取物的体外抗氧化及乙酰胆碱酯酶抑制能力

以沙棘叶为原料,以DPPH?清除能力、总还原力为指标,评估沙棘叶提取物的体外抗氧化活性,并以沙棘叶提取物对乙酰胆碱酯酶的抑制能力为指标,考察其成为乙酰胆碱酯酶抑制剂的潜力。研究结果表明：5种不同乙醇体积分数的（40%、50%、60%、70%、80%）沙棘叶提取物均有较好的抗氧化活性与对乙酰胆碱酯酶抑制能力。以60%乙醇提取的沙棘叶提取物的DPPH?清除率、总还原力及乙酰胆碱酯酶抑制能力最强,分别为（85.80±1.39）%,3.06±0.18,（97.14±0.809）%,可作为抗氧化剂与乙酰胆碱酯酶抑制剂。筛选后的沙棘叶提取物对乙酰胆碱酯酶有较强的抑制能力,半数抑制质量浓度（IC50）值为（1.086±0.144）mg/mL,并且根据酶的抑制动力学分析得出对乙酰胆碱酯酶是竞争性大于非竞争性的混合可逆抑制类型。AutoDock分子对接结果也表明,沙棘叶活性成分与乙酰胆碱酯酶具有一定的对接亲和力。剂效相关性分析表明沙棘叶提取物的抗氧化、酶抑制活性与功能成分之间均存在良好的正相关性（P<0.05）,沙棘叶提取物中起主要抗氧化与酶抑制作用的成分为多酚类化合物.     

固定化酶技术及其载体材料研究

固定化酶技术已经成为酶应用领域中的一个重要研究方向，此技术可以有效地提高酶的催化性能和操作稳定性，为酶在大规模生产中提供有利条件。载体作为固定化酶技术的关键组成部分，其材料的选择对于固定化酶技术的性能至关重要。本文对比了目前载体材料的特点并总结了固定化酶筛选方法，以期为后续固定化酶技术的研究提供基础。     

酶固定化技术研究进展

酶的固定化技术是酶工程领域研究的重点和热点之一,本文阐述了传统的酶固定化技术,并对定向固定、多酶共固、新型载体等前沿技术做了介绍,另外还对固定化酶的应用前景和发展趋势进行了预测.     

A novel electron beam-based method for the immobilization of trypsin on poly(ethersulfone) and poly(vinylidene fluoride) membranes

A novel technique for the covalent immobilization of trypsin in a one-step reaction using low-energy electron beam is described. The enzyme immobilization was applied on poly(ethersulfone) and poly(vinylidene fluoride) microfiltration membranes. For this purpose, the membranes were dipped in an aqueous solution of trypsin followed by electron beam treatment.The effect of irradiation conditions on the immobilization was investigated, as well as the resulting membrane properties with respect to enzymatic activity, immobilized enzyme concentration, pure water flux, scanning electron microscopy, and porosimetry. This technique shall provide a simple, inexpensive method for enzyme immobilization on various polymer membranes and offer a tool for the application in enzymatic membrane reactors.     

Bioinformatic Analysis of Immobilized Enzymes: Towards a Better Understanding of The Guiding Forces

Protein bioinformatics has been applied to a myriad of opportunities in biocatalysis from enzyme engineering to enzyme discovery, but its application in enzyme immobilization is still very limited. Enzyme immobilization brings clear advantages in terms of sustainability and cost-efficiency but is still limited in its implementation. This, because it is a technique that remains tied to a quasi-blind protocol of trial and error, and therefore, is regarded as a time-intensive and costly approach. Here, we present the use of a set of bioinformatic tools to rationalize the results of protein immobilization that have been previously described. The study of proteins with these new tools allows the discovery of key driving forces in the process of immobilization that explain the obtained results, moving us a step closer to the final goal: predictive enzyme immobilization protocols.     

固定化酶制备技术的研究进展

固定化酶便于运输和贮存,有利于自动化生产,是近十余年发展起来的酶应用技术,在工业生产、化学分析和医药等方面有诱人的应用前景。本文对传统固定化技术的改进,载体材料的改性以及新型固定化技术的开发等方面的研究进展进行了综述。     

固定化细胞载体材料的研究进展

固定化细胞技术是在固定化酶的基础上发展起来的高新技术,所用载体材料的性能是此项技术的关键。详细介绍了固定化细胞技术中常用载体材料的种类及其性能,概述了新近出现的载体材料及其应用,最后对载体材料的未来发展进行了预测。     

UV polymerization‐based surface modification technique for the production of bioactive packaging

The term bio‐active packaging refers to a packaging material that has been modified by the attachment or immobilization of bioactive components on the food contact surface. This article describes a novel, economical, and feasible technique for embedding bioactive components in energy curable food contact resins. While the technique is versatile and potentially applicable to any antimicrobial or bioactive compound; the proof of concept discussed in this article has focused on enzyme immobilization. Glucose oxidase (GOx) and catalase were used as representative enzymes. These oxidoreductases are very sensitive to inactivation by extrinsic factors and therefore present a challenging model for immobilization. Embedding of activity occurred via UV polymerization of commercial polymer coatings. The efficiency of immobilization and the performance of bioactive packaging were tested in both food simulants and actual food products. In both cases immobilization resulted in food contact surfaces with high retained enzyme activity as demonstrated by oxygen removal. © 2007 Wiley Periodicals, Inc. J Appl Polym Sci, 2008     

酶工程在医药工业中的应用

酶工程是现代生物技术的重要组成部分,它作为一项高新技术将为各工业的发展起重要推动作用。介绍了酶固定化、基因工程菌(细胞)的固定化、植物细胞培养产酶、酶的化学修饰、核酸酶、抗体酶、酶标药物的理论和技术研究的最新进展以及酶工程在医药工业中的应用,对酶工程的发展前景进行了探讨。     

Preparation and characterization of polymer-coated mesoporous silica nanoparticles and their application in Subtilisin immobilization

The preparation and characterization of polymer-coated mesoporous silica nanoparticles (MSNs) and their application in Subtilisin (Alcalase®) immobilization were investigated. For the synthesis of polymer-coated MSNs, acrylic acid (AA) and chitosan (CS) mixture were blended as poly(acrylic acid) (PAA) and CS polymer layer onto MSNs via in-situ polymerization technique. Then, both uncoated MSNs and polymer-coated mesoporous silica nanoparticles (CS-PAA/MSNs) were characterized by taking into account properties such as morphologic pattern, size distribution, surface charge of the particles as well as thermogravimetric stability with SEM, TEM, Zetasizer and TGA analyses. Subtilisin was immobilized onto polymer-coated mesoporous silica nanoparticles via adsorption technique. For optimizing the enzyme immobilization process, the percent enzyme loading depending on the matrix amount, immobilization time and pH were investigated. Then, the activity values of immobilized enzyme and free enzyme were compared at various pH and temperature values. The maximum enzyme activity was achieved at pH 9.0 for both immobilized and free enzyme. Immobilized enzyme showed more stability at higher temperatures compared with free enzyme. Furthermore, the operational and storage stability of immobilized enzyme were determined. The activity of immobilized enzyme was reduced from 100% to 45.83% after five repeated uses. The storage stability of immobilized enzyme was found to be higher than that of free enzyme. The activity of immobilized enzyme was reduced from 100% to 60% after 28 days of storage time. We concluded that the polymer-coated MSNs were a suitable matrix for Subtilisin immobilization compared to uncoated MSNs.     

无机材料在酶固定化中的应用

综述了近年来无机材料在国内外酶固定化研究中的应用,着重介绍了载体材料的表面处理方法及相应的酶固定化方法,并对无机材料在酶固定化中的应用作了展望。     

固定化酶研究进展

固定化酶有许多优点,尤其是稳定性和可重复使用性使其在许多领域得到广泛应用.固定化酶技术是一门交叉学科技术,目前已得到长足的发展.介绍了固定化酶制备的传统方法以及一些新方法,同时对酶在一些性能优良的载体上的固定进行了综述.