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。     

酶工程研究及应用

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各工业中的应用，对酶工程的发展前景进行了探讨。     

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.     

酶工程技术与进展

简述了酶工程研究领域的主要内容。包括酶的分离与纯化，固定化酶、人工合成酶、模拟酶、ribozyme、抗体酶、杂交酶、非水系酶等的开发与应用，基因工程和蛋白质工程技术、分子压印技术、酶定向固定化技术、酶化学技术以及极端环境微生物和不可培养微生物的新酶种等现代酶工程技术研究领域的新进展及酶工程的应用。     

酶生物传感器中的胆碱酯酶固定化技术

乙酰胆碱酯酶(AChE)是一种重要的工具酶,酶的固定化技术研究已成为酶工程的重要组成部分。综述了酶固定化技术发展概况,介绍了酶生物传感器中酶的固定化方法、固定化技术、乙酰胆碱酯酶固定化所用载体及固定化技术的研究进展。     

酶在环境保护方面的应用

介绍了酶工程基本技术,包括酶制剂的生产、酶的分离纯化、酶的固定化技术、酶的改造和修饰等,综述了酶在环境保护方面,包括水净化、石油和工业废油的处理、白色污染的治理和环境监测等方面的研究和应用现状.     

细胞固定化载体材料的研究进展及应用

文章简述了细胞固定化技术,介绍了近年来国内外细胞固定化载体材料研究的新进展,常用的载体材料的比较分类,选择及它们在固定化技术中的应用,并展望了细胞固定化材料的发展前景。     

藻类固定化技术研究进展及发展趋势

本文综述了固定化藻类细胞的制备技术、载体特性及固定化对藻类生理的影响,并分析了藻类固定化技术在污水处理中的应用,及目前存在的问题和今后的发展趋势.     

固定化细胞技术发酵产氢的应用研究

微生物发酵产氢的固定化细胞技术与其非固定化细胞技术相比,前者具有很大的优越性,能显著提高发酵系统的产氢量。对微生物发酵产氢固定化细胞的制备方法及其应用载体进行了介绍,分析了国内外固定化细胞技术在厌氧产氢中的最新进展,指出了固定化细胞技术发酵产氢存在的问题,并对其发展进行了探讨。     

生物技术应用的进展与前景（Ⅱ）

4 轻化生物技术 轻化生物技术以生产特定产品的酶工程和发酵工程为重点,与基因工程、细胞工程融为一体,成为应用面广、投入产出比高的领域,在为人类解决食品、能源和环境污染等危机中起着举足轻重的作用。 4.1 酶与细胞固定化技术 生物技术是既古老又年轻的科学。古时候人们     

Immobilization of microbial cells on cellulose–polymer surfaces by radiation polymerization

Streptomyces phaeochromogenes cells were immobilized on cellulose–polymer surfaces by radiation polymerization using hydrophilic monomers and paper. The enzyme activity of immobilized cell sheets was higher than that of immobilized cell composites obtained by the usual radiation polymerization technique. The enzyme activity of the sheets was affected by monomer concentration, the thickness of paper, and the degree of polymerization of paper. The copolymerization of hydroxyethyl methacrylate and methoxytetraethyleneglycol methacrylate in the sheets led to a further increase of the enzyme activity due to the increase of the hydrophilicity of the polymer matrix. The Michaelis constant of the sheets from low monomer concentration was close to that of intact cells.     

Immobilization of mortierella vinacea cells by radiation polymerization

Immobilization of Mortierella vinacea cells, which contain active α-galactosidase, by radiation polymerization at low temperatures was studied. The durability of the enzymatic activity of the immobilized cells was examined by repeating the batch enzyme reaction. The enzymatic activities of the immobilized cells obtained with hydrophilic monomers was affected by the concentrations of the cells and monomer in which optimum conditions were observed. The enzymatic activity of the immobilized cells obtained with hydrophilic monomer was compared to that of hydrophobic monomers. Michaelis constants of the immobilized cells varied with monomer concentration. The effect of addition of porous solid substances on the immobilization of the cells was studied.     

固定化微生物处理造纸漂白废水

将驯化6个月后所得的、对氯代芳香类有机物（AOX）具有高效降解作用的混合菌,用聚乙烯醇（PVA）包埋后,在厌氧条件下处理含AOX废水,并与自由菌液做比较。结果表明：固定化细胞的酶活性及AOX去除率均高于自由菌液,对温度和pH的适应范围较宽;菌体包埋量及反应液中湿菌含量是影响固定化细胞处理AOX废水酶活性的主要因素。在对造纸漂白废水为期1个月的连续处理试验表明,在停留时间为2．4h时,其去除率可稳定在65％－81％。     

固定床反应器培养固定化大肠杆菌生产β-葡聚糖酶

以多孔陶瓷为载体吸附法固定重组大肠杆菌E. coli JM 109-pLF3表达胞外β-葡聚糖酶。考察了固定床间歇培养时循环流速和曝气量对发酵液酶活力的影响。当循环流速达到44.19 mL/min,曝气量达到0.6 mL/min时,培养48 h后,发酵液的酶活力达100.3 U/mL。固定化细胞具有良好的重复使用能力,在连续5批次实验中,培养48 h后的酶活力均在100 U/mL左右。固定床连续培养时,固定化细胞能够保持恒定的产酶效率,当稀释率为0.05 h－1时,发酵液中得到的酶活力为39.1 U/mL。     

Hydrolysis of milk lactose in a packed bed reactor system using immobilized yeast cells

BACKGROUND: Hydrolysis of lactose with β‐D‐galactosidase is one of the most promising biotechnological applications in the food industry because of its use in the production of low lactose milk products and whey hydrolysis. To overcome the problem of enzyme extraction from cells due to the intracellular nature of β‐D‐galactosidase and the poor permeability of the cell membrane to lactose, permeabilization of yeast cells was investigated. Permeabilized whole cells have been claimed to have an advantage over more pure enzyme preparations. In view of the advantages of immobilized cell systems over free cell systems, permeabilized cells were immobilized by an entrapment method in calcium alginate gel. A packed bed reactor together with this immobilized cell system has been used for hydrolysis of milk lactose in a continuous system. RESULTS: Different process parameters (temperature, substrate feed rate, biomass load and time‐course) were optimized to maximize lactose hydrolysis. The immobilized yeast cells (300 mg dry wt) resulted in 87.2% hydrolysis of milk lactose at 30 °C and flow rate 7 mL h^?1 in a packed bed reactor system. CONCLUSION: This convenient and relatively inexpensive method of immobilization, resulting in high hydrolysis potential in a continuous system, indicates that permeabilized yeast cells have the potential for the production of low lactose milk and milk products. Copyright © 2010 Society of Chemical Industry     

海藻酸钠-明胶协同固定化S-腺苷甲硫氨酸合成酶的研究

以海藻酸钠和明胶为载体,对S-腺苷甲硫氨酸合成酶进行固定化。再用戊二醛对其进一步交联,增强固定化酶的稳定性。考察了海藻酸钠和明胶质量分数、CaCl2质量分数、酶和载体比例以及交联剂戊二醛体积分数等因素对固定化酶的影响。结果表明,最佳固定化条件为:海藻酸钠质量分数2.0%、明胶质量分数1.0%、CaCl2质量分数4.0%、固定化酶量为2.5 g/L凝胶、戊二醛体积分数0.6%。交联固定化酶热稳定性得到大幅度提高,在50℃下保温5 h仍保留72%的活力,而游离酶则完全失活。交联固定化酶在碱性溶液中的稳定性较高,在pH=8.0～9.0的缓冲液中4℃保温10 h酶活性仍保留87%以上。将交联固定化酶用于S-腺苷甲硫氨酸的合成,连续反应8批次后酶活性仍保留65%。     

Lipolytic activity in free and immobilized cells of Phoma glomerata

The lipolytic activity of free and immobilized whole cells of the pathogenic fungus Phoma glomerata was demonstrated, and several properties of the lipase involved were determined. Free fungal cells and small pieces of immobilized cells, prepared by spontaneous colonization on a solid surface or entrapped in calcium alginate, were incubated with triolein in buffered medium. Different incubation conditions were assayed to optimize the reaction, to determine the effects of heating and time on stability of the immobilized preparations and the time course of the reactions. Although the enzyme cleaves all ester bonds of triolein, it shows some preference for the outer bonds. An optimal pH of 7.5–8.0, optimal temperature of 45°C for free and 50°C for immobilized cell preparations, the necessity for substrate emulsifiers, and reaction independence from calcium and magnesium were demonstrated. Results suggest that immobilized whole cells of P. glomerata would be a suitable tool to study its lipid physiology and to explore further the possible biotechnological use of its lipase activity.     

超声波对固定化辣根过氧化物酶活性影响研究

为了研究超声波对固定化酶活性的影响,以固定化辣根过氧化物酶为对象,研究了不同超声波处理条件(超声功率,超声时间)以及超声条件下催化体系的pH、温度对固定化酶活性的作用。同时对超声波处理后固定化酶活的重复利用性进行测定。结果表明,超声波处理对提高固定化酶在高温、强酸碱条件下催化活性有一定帮助,最佳处理条件为:超声波功率50 W,超声时间30 min,pH 8,温度35℃,在此条件下,与未经超声波处理相比,固定化酶活性提高了17.6%,固定化酶重复利用性增强,经7次使用后,固定化酶催化活性是未经处理的1.8倍。     

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.     

海藻酸钠固定化S-腺苷甲硫氨酸合成酶的制备及其性质研究

研究了以海藻酸钠包埋法制备固定化S-腺苷甲硫氨酸（sAM）合成酶的条件,并考察了固定化酶的酶学性质。结果表明,最适固定化条件为：海藻酸钠质量分数3％、CaCl2质量分数4％、SAM合成酶加量（以每克海藻酸钠计）75mg、固定化时问30min,在此条件下,固定化酶活力回收率达到42％。固定化酶热稳定性较好,在50℃下保温5h仍保留69％的酶活力,而游离酶则完全失活;固定化酶在碱性条件下的稳定性较好,在pH值7．5～9．0的缓冲溶液中4℃下保温10h仍保留84％以上的酶活力;将固定化酶用于SAM的合成,连续反应5批次后,仍保留82％的酶活力。