深度共熔溶剂中环氧化物水解酶催化环氧化物不对称水解反应的研究

Novel biocompatible and biodegradable deep eutectic solvents (DES) with low viscosity will be rationally designed and synthesized in the project. The enzymatic asymmetric hydrolysis of epoxides with various epoxide hydrolases (EHs) from different sources will be comparatively studied in various reaction media to elucidate how DES affects the initial reaction rate, the enantioselectivity and the yield of the reaction, as well as the enzymes' stability, thus correlating the structure and the physicochemical properties of DESs with the catalytic performance of EHs. The mechanism of DES’s effect on enzymatic asymmetric hydrolysis of epoxides with EHs can be revealed by combining the above-mentioned results with the investigations on the kinetics of EHs-catalyzed asymmetric hydrolysis of epoxides in various DES-containing reaction systems and the distribution of various substances in the reaction systems, as well as the influences of different DESs on the molecular structure of EHs. The impact of several key factors on the enzymatic process will be explored systematically and a highly efficient and selective enzymatic approach to enantiopure chiral diols will be well established, from which self-owned intellectual property right will be obtained. Additionally, the established biocatalytic route will be used for the synthesis of several important chiral vicinal diols. The study on the influential law and mechanism of the novel DES on the catalytic performances of EHs will lay a good theoretical foundation for the application of novel DES in biocatalysis. Also, the investigation regarding the structure-catalytic performance relationship of EHs in the novel DES-containing systems will provide some useful information on how to design and establish highly efficient enzymatic processes.

理性设计并合成低粘度、生物相容、生物可降解的新型深度共熔溶剂（DES），通过对比研究不同介质中不同来源的环氧化物水解酶(EHs)催化环氧化物不对称水解合成手性邻二醇的反应特性，阐明DES对反应速度、对映体选择性、产率及酶稳定性等的影响规律，总结DES的结构及性质与EHs催化特性的关系；结合不同介质中EHs催化环氧化物水解反应的动力学、各物质在反应体系中的分配规律、不同DES对EHs分子结构的影响之研究，揭示DES对EHs催化该反应影响的机理；系统考察各主要因素对该反应的影响规律，建立可望取得自主知识产权、可广泛用于高效、高选择性合成手性邻二醇的生物催化反应体系，合成几种具有重要价值的手性邻二醇。DES对EHs催化特性的影响规律及机理的研究将奠定其用于生物催化的理论基础；含DES介质中酶结构与催化特性关系的研究将为高效酶催化体系的设计与构建提供理论指导。

本研究理性设计并合成了一系列低粘度、生物相容、生物可降解的新型DES，通过对比研究不同介质中不同来源的环氧化物水解酶(EHs)催化环氧化物不对称水解合成手性邻二醇的反应特性，阐明DES对该反应速度、对映体选择性、产率及酶稳定性的影响规律，总结DES的组成及性质与EHs催化特性的关系；结合不同介质中EHs催化环氧化物水解反应的动力学、各物质在反应体系中的分配规律、不同DES对EHs分子结构的影响之研究，揭示DES对EHs催化该反应的影响机理；此外，针对天然EHs对映选择性（E值）偏低，酶活性较差的问题，采用定向进化的手段对其进行改造，获得了催化性能显著提高的酶制剂；最终，建立了高效、高选择性的生物催化反应体系用于对映体纯手性邻二醇的合成。本项目在研究内容、研究成果等方面均超额完成了任务。以上研究工作已发表一系列高水平论文30余篇，主要刊物为 Chem. Eng. J., Green Chem.,ChemSusChem, Biotechnol. Bioeng., ACS Sustain. Chem. Eng., J. Agr. Food Chem.等。申请中国发明专利20项，获授权中国专利4项。该研究为深度共熔溶剂应用于生物催化奠定了一定的理论基础，且具有较好的应用潜力。