我国化学工业“十一五”期间技术进步与创新方向

1努力发展高新技术 新催化技术重点是合成氨催化技术、生物催化技术、高分子聚合物催化技术、碳一化学新型催化技术、环保催化技术、酶催化技术、新催化材料的研制及应用技术。进行催化反应器放大、设计和制造研究。     

微生物酶分离纯化研究进展

在对常规的微生物酶分离纯化方法如沉淀法、疏水层析、凝胶过滤、离子交换层析及亲和层析等的特点、原理及应用进行介绍的基础上,概述了膜处理技术、免疫纯化技术、双水相体系萃取等新颖微生物酶分离纯化技术。指出常规方法和新颖方法的结合为微生物酶带来了高效的分离纯化效果,开发先进、灵活的蛋白质化学技术分离纯化天然酶、重组酶、人工模拟酶及杂合酶势在必行。     

酶催化超分子自组装及其在癌症诊疗中的应用研究进展

自组装是自然界的普遍现象,也是构建超分子生物材料的有力工具。在众多方法中,酶催化超分子自组装具有优异的肿瘤靶向性及良好的生物安全性,是近年来癌症诊疗的一个重要新方向。针对这一趋势,本文简介了酶催化超分子自组装在细胞内、外的构建方法,详细总结了其在癌症诊疗中的应用。研究表明,酶催化超分子自组装材料在生物医学成像、选择性杀死癌细胞、药物递送和克服药物不良反应方面具有潜在的应用价值。提出了体内超分子组装体的微观形貌需要明确表征、构建自组装方法的酶范围需要扩展以及需要探索酶催化超分子自组装（EISA）与亚细胞器的相互作用等解决其发展中的问题的思路和方向,并对其在抗菌药物开发、免疫调节、创伤修复和组织再生领域的潜在应用作出了展望。     

生物催化技术在化学制药中的应用

生物催化技术是一种利用酶或微生物进行化学反应的技术,通过生物体内的天然催化系统实现选择性、高效和温和的化学合成或分解。在有机合成、制药、食品工业和环境保护等领域,生物催化技术展现出高度优越性。其优势包括高选择性、高效催化、温和反应条件、对复杂底物的容忍度、可再生性和环境友好。特别在制药领域,裂解酶、氧化酶、还原酶和转移酶等酶催化技术被广泛应用,提供了高效、选择性和可持续的药物合成解决方案。随着对生物催化技术的深入理解和生物技术的发展,其未来应用前景广阔。     

漆酶的固定化技术及固定化漆酶载体材料研究进展

漆酶作为一种含铜的多酚氧化酶,可催化降解多种有机污染物且发生反应后唯一的产物是水。漆酶具有催化效率高、贮存要求低等优点,在酶催化领域得到了广泛的关注。漆酶固定化技术是通过物理或化学的方法将游离漆酶和相应载体材料结合起来。与游离漆酶相比,固定化漆酶表现出更高的重复使用性以及在温度、pH、储存、操作方面表现出更高的稳定性。结合目前固定化漆酶技术的研究现状和应用情况,文中介绍了漆酶的结构特征和催化特性,并综述了漆酶固定化技术和固定化漆酶载体材料的研究进展,指出了漆酶的固定化技术和载体材料目前存在的问题和未来的发展前景,旨在为进一步对固定化漆酶的研究和开发应用提供参考依据。     

酶催化技术在医药工业中的应用

近10年来,随着生物技术的发展,酶催化技术已愈来愈多地用于有机合成,特别是不对称合成、光学活性化合物及天然产物的合成,已在医药、食品、轻工业、纺织等行业中得到越来越广泛的应用。本文介绍了酶和细胞固定化、非水相介质中的酶催化、低共熔酶催化反应和酶催化反应与分离的耦合等酶催化技术的研究进展,以及酶催化技术在制药工业和临床诊断及治疗上的应用。     

生物催化反应的应用

生物催化是21世纪研究比较多的一门技术,有其相对于化学催化显著的优越性,发展比较快的酶催化及抗体催化,重点介绍对其在工业催化,手性药物合成方面的应用,简要介绍在环境保护方面应用。     

“酶+X”耦合催化CO2资源化转化

“碳达峰、碳中和”是我国统筹国内外局势做出的重大战略决策,是着力解决资源环境约束突出问题、构建人类命运共同体的庄严承诺。碳捕集与封存技术(CCS)作为传统的CO₂治理方法存在潜在的泄漏风险且会造成巨大的经济负担。近年来,碳捕集、利用与封存技术(CCUS)由于可将捕集的CO₂转化为附加值产品以实现资源化利用,被认为是CCS的有效替代和补充方案。发展高效的CO₂资源化技术是CCUS的关键。酶催化技术作为典型的绿色生物制造技术在CO₂资源化利用领域受到广泛关注。构建以酶催化为基础的耦合催化系统为CO₂到高值化学品或燃料的资源化转化创造了丰富的路径网络。综述了近年来基于生物酶介导的“酶+X”耦合催化CO₂资源化转化系统,包括“酶+酶”耦合催化系统、“酶+化学”耦合催化系统、“酶+光”耦合催化系统和“酶+电”耦合催化系统。对不同耦合催化系统的结构进行解析,明确了系统特点及催化反应过程。在结构解析的基础上讨论了系统模块设计与性能强化的关键。阐述了“酶+X”耦合催化系统...     

利用同源片段交换提高腈水合酶的热稳定性

目的通过计算机辅助半理性设计对热不稳定的恶臭假单胞菌Psedomonas putida NRRL-18668腈水合酶(EC4.2.1.84,nitrile hydratase,简称NHase)分子进行改造,提高酶催化的热稳定性和活性。方法以嗜热假诺卡菌Pseudonocardia thermophila JCM3095和睾丸酮丛毛单胞菌Comamonas testosterone 5-MGAM-4DNHase作为模板,利用位点靶向氨基酸重组(site-targeted amino acid recombination,STAR)软件和分子动力学模拟分析选择合适的同源靶片段,通过同源交换替换Pseudomonas putida NRRL-18668NHase相应的片段,构建7株分别含有3种不同来源片段的新型杂合NHase,检测其热稳定性及活性;圆二色光谱分析野生酶和杂合酶3AB的二级结构。结果 7株杂合NHase(1A、2B、2C、2BC、3AB、3AC、3ABC)经50℃热处理10 min后,与野生型NHase相比,热稳定性分别提高了1.5~3.5倍,其中杂合NHase 3AB的热稳定性提高了3.5倍,酶活力提高了1.4倍;野生酶和杂合酶3AB二级结构中α螺旋含量分别为(34.56±3.21)%和(36.88±1.41)%,,β折叠含量分别为(19.78±3.21)%和(18.69±1.74)%。结论通过利用热稳定性的同源片段来替换相应的热不稳定结构域这种理性设计的方法,成功将不耐热的NHase改造成耐热杂合NHase,同时提高了酶的比活力,并能维持NHase分子的基本二级结构不改变。     

漆酶固定化磁性载体的研究进展

漆酶是一种多铜氧化酶,催化效率高且催化反应的唯一副产物是水,是一种绿色环保的生物催化剂。漆酶催化底物范围广,在多个领域都有重要应用潜能。磁性载体固定漆酶可实现漆酶的磁性回收和重复使用、降低漆酶的使用成本、提高漆酶的稳定性,近年来已成为漆酶固定化研究的热点。对不同漆酶固定化磁性载体的制备方法、固定化漆酶的催化性能及应用进行了综述,比较分析了不同磁性载体的负载量和固定化漆酶的活性回复率,为漆酶固定化磁性载体的开发应用提供帮助。     

Polymer-supported enzymes: Achievements,problems and perspectives

Over the last two decades, intense research activity in the area of enzyme and cell immobilisation techniques has fostered the industrial application of several new enzyme-catalysed processes for chemical and pharmaceutical production, as well as for the food industry. Biosensors, based on immobilised enzymes or whole cells, are finding wide-spread applications in the analytical and biomedical fields. The recent remarkable progress attained in the development of recombinant DNA techniques promises to provide any enzyme having properties tailored to meet the specific demands of any user.     

纳米酶催化剂制备方法研究进展

酶催化具有化学、区位和立体选择性,这使得其成为绿色合成化学品的理想催化剂。然而,天然酶常因其在工业催化条件下的活性和稳定性较低而难以使用。纳米技术为构建高效酶催化剂提供了新的可能性。通过简便、高效、低成本的方法制备出具有高催化活性和高稳定性的纳米酶催化剂,同时提高纳米酶催化剂的可操作性和可回收重复使用特性是其中的关键问题。介绍了纳米酶催化剂的研究现状和制备方法,重点介绍了采用共沉淀方法制备酶-无机晶体杂化纳米催化剂、酶-金属有机骨架材料杂化纳米催化剂,以及制备具有温度和磁响应特性的纳米酶催化剂,并对纳米酶催化剂在酶催化合成医药化学品方面的应用前景进行了探讨。     

An automatic dehydrogenase-based flow-injection system: Application for the continuous determination of glucose and lactate in mammalian cell-cultures

A concept for the development of an automatic flow-injection analyzer with integrated dehydrogenase columns and its application in the control of industrial processes is presented. The system is based upon a kernel consisting of a nested-loop injection unit, pumps for the filling of the injection loops and the transport of buffer and valves for switching on the one hand between sample and standard solutions and on the other hand between different enzyme columns. A Microsoft Windows 3.x application ‘WIN-FIA’ controls interactively the whole system and can be easily adapted to a specific solution of an analytical problem. As an example, the flow-injection system was used for the continuous determination of glucose and lactate, using glucose dehydrogenase (GDH) and lactate dehydrogenase (LDH) as indicator enzymes, in a mammalian cell-culture fermentation process. The resulting concentration values are in good agreement with those obtained by discontinuously taken standard spectrophotometric enzyme assays.     

Nickel-Carnosine complex:A new carrier for enzymes immobilization by affinity adsorption

Immobilization is an effective method to promote the application of enzyme industry for improving the stability and realizing recovery of enzyme.To some extent,the performance of immobilized enzyme depends on the choice of carrier material.Therefore,the development of new carrier materials has been one of the key issues concerned by enzyme immobilization researchers.In this work,a novel organic-inorganic hybrid material,nickel-carnosine complex (NiCar),was synthesized for the first time by solvothermal method.The obtained NiCar exhibits spherical morphology,hierarchical porosity and abun-dant unsaturated coordination nickel ions,which provide excellent anchoring sites for the immobiliza-tion of proteins.His-tagged organophosphate-degrading enzyme (OpdA) and ω-transaminase (ω-TA)were used as model enzymes to evaluate the performance of NiCar as a carrier.By a simple adsorption process,the enzyme molecules can be fixed on the particles of NiCar,and the stability and reusability are significantly improved.The analysis of protein adsorption on NiCar verified that the affinity adsorp-tion between the imidazole functional group on the protein and the unsaturated coordination nickel ions on NiCar was the main force in the immobilization process,which provided an idea way for the develop-ment of new enzyme immobilization carriers.     

Characterizing the properties and evaluating the efficiency of biocatalysts based on immobilized fungal amylase

Preparations based on native enzymes have limited industrial use because of their instability and sensitivity to the changes in pH, temperature, and other external factors. It is therefore essential to create biocatalysts based on immobilized enzymes that are more stable and thus more efficient in practical application. To stabilize fungal amylase (EC 3.2.1.1.), the enzyme is covalently immobilized on a chitosan-containing cellulose. It is shown that the thermal stability of the immobilized amylase is increased by 350%, compared to the native enzyme, and its resistance to pH-inactivation is also improved. The reduction of the inactivation rate constant and the increase of the Gibbs free energy for the immobilized enzyme, relative to the native enzyme, testify to its increased stability resulting from steric factors associated with the formation of azomethine bonds with cellulose and chitosan. It is shown that using the immobilized enzyme preparation instead of the native amylase increases the product yield in barley malt hydrolysis by a factor of 1.5, allowing us to use this preparation in the food industry.     

Spouted Bed Drying as a Method for Enzyme Immobilization

Usually immobilization is a requirement for the use of enzymes as an industrial biocatalyst. In this work, endophytic fungus Cercospora kikuchii lipase was immobilized by covalent binding on agricultural by-products and microcrystalline cellulose. The enzyme support system was submitted to spouted bed drying. Lipase immobilized on microcrystalline cellulose with 1.5% of glutaraldehyde showed the best results, presenting 179.1% of the original activity after drying, followed by rice husk (173.9%), corn stover (169.8%), sugarcane bagasse (157.3%), green coconut fiber (102.3%), and corncob (99.8%). The immobilized derivatives obtained showed a decreased enzyme activity with an average of only 17.31%, whereas the enzyme in its free form lost 85.8% of its initial activity after storage for 6 months. The operational stability showed that the biocatalysts prepared retained an average of 67.2% of the initial activity after five reuse cycles. The results showed that the use of agricultural by-products as low-cost support material associated with the spouted bed drying is promising and can contribute to industrial application of biocatalysts.     

Multi-enzyme cascade reaction in a miniplant two-phase-system: Model validation and mathematical optimization

Biotechnological application of multiple enzymes in different phases for target compounds synthesis poses a significant challenge for industrial process development. At the same time, a growing demand for natural flavors and fragrances opens up possibilities for novel biotechnological processes to replace current chemical synthesis routes, with additional advantages such as avoiding harsh reaction conditions and toxic chemicals, and less by-products in the system. Within complex biotechnological processes, the key for unfolding their industrial application potential in bioprocess engineering lies in their mathematical modeling. In this contribution, a multi-enzyme cascade reaction in a two-phase system implemented in a miniplant-scale reactor setup is mathematically modeled for the example of the flavoring agent cinnamyl cinnamate. Using our validated model and a mathematical optimization tool based on a genetic algorithm, optimization runs are performed to demonstrate the potential of computer-aided process development for complex biotechnological processes.     

Joining of polymers and polymer–metal hybrid structures: Recent developments and trends

The development of new materials and fabrication techniques has become a matter of success for industrial sectors such as transportation. Polymers, polymeric composites, and polymer–metal structures are being increasingly employed in several products mainly due to the associated weight savings. The main joining methods for polymer and polymeric composites are mechanical fastening, adhesive bonding, and welding. On the other hand, polymer–metal structures are more difficult to join by traditional joining methods, mostly due to their strong dissimilar physical–chemical features. Constant efforts on developing improved alternative joining techniques for these hybrid structures, such as the FricRiveting and injection over molding, have contributed to the dissemination of such structures in industrial applications. This work shows that the field of joining of polymers, polymeric composites, and polymer–metal hybrid structures for industrial applications is still a growing research and development area. This is due to the increasing aspirations for more environmental‐friendly technologies and lightweight materials. POLYM. ENG. SCI., 2009. © 2009 Society of Plastics Engineers     

Improving Colorimetric Assays through Protein Enzyme-Assisted Gold Nanoparticle Amplification

The discovery of the DNA-mediated assembly of gold nanoparticles was a great moment in the history of science; this understanding and chemical control enabled the rational design of functional nanomaterials as novel probes in biodetection. In contrast with conventional probes such as organic dyes, gold nanoparticles exhibit high photostability and unique size-dependent optical properties. Because of their high extinction coefficients and strong distance dependent optical properties, these nanoparticles have emerged over the past decade as a promising platform for rapid, highly sensitive colorimetric assays that allow for the visual detection of low concentrations of metal ions, small molecules, and biomacromolecules. These discoveries have deepened our knowledge of biological phenomena and facilitated the development of many new diagnostic and therapeutic tools. Despite these many advances and continued research efforts, current nanoparticle-based colorimetric detection systems still suffer from several drawbacks, such as limited sensitivity and selectivity. This Account describes the recent development of colorimetric assays based on protein enzyme-assisted gold nanoparticle amplification. The benefits of such detection systems include significantly improved detection sensitivity and selectivity. First, we discuss the general design of enzyme-modified nanoparticle systems in colorimetric assays. We show that a quantitative understanding of the unique properties of different enzymes is paramount for effective biological assays. We then examine the assays for nucleic acid detection based on different types of enzymes, including endonucleases, ligases, and polymerases. For each of these assays, we identify the underlying principles that contribute to the enhanced detection capability of nanoparticle systems and illustrate them with selected examples. Furthermore, we demonstrate that the combination of gold nanoparticles and specific enzymes can probe enzyme dynamics and function with high specificity, offering substantial advantages in both sensitivity and specificity over conventional detection methods. The screening of nuclease, methyltransferase, protease, and kinase activities can be colorimetrically performed in a straightforward manner. Finally, we discuss examples of colorimetric assays for metal ions and small molecules that constitute important advances toward visual monitoring of enzyme catalytic functions and gene expression. Although these enzyme-assisted assay methods hold great promise for myriad applications in biomedicine and bioimaging, the application of the described techniques in vivo faces formidable challenges. In addition, researchers do not fully understand the interactions of gold nanoparticles with enzyme molecules. This understanding will require the development of new techniques to probe enzyme substrate dynamics at the particle interface with higher spatial resolution and chemical specificity.