Bioactive Pickering emulsions for sustainable oxyfunctionalization

氧官能化反应是有机化学合成中的一个关键步骤。关于环境保护和可持续性，非常需要用过氧化氢或分子氧代替目前使用的高毒性氧化剂如铬酸盐。各种酶如脂肪酶和过加氧酶和单加氧酶在温和和选择性条件下催化这些反应。然而，由于缺乏合适的技术，既照顾到氧功能化反应的具体特点和生物催化剂的具体性质，生物基氧功能化还很少被用于合成。基于从以前的联合项目中获得的知识，我们在这里提出，在连续膜反应器中的生物活性皮克林乳液（BioPE）可能是这种技术的可行基础。我们认为，无论是生物催化剂的配方或其放置在液-液界面，分别，和BioPE的物理性质可以优化，以提高合成性能。因此，该项目系统地研究了BioPE在连续膜反应器中的应用，用于使用不同复杂的生物催化剂（脂肪酶，过加氧酶和单加氧酶）对有机化合物进行可持续的生物催化氧化官能化，同时考虑到催化系统，反应技术及其相互作用的具体特征。它解决了基本问题，如果，或可能的生物催化的氧官能化受益于实施到皮克林乳液，并将确定和优化关键参数（如液滴大小，界面面积，生物催化剂负载和位置，基板供应，相组成），决定了反应系统的催化性能。与生物技术和工程合作伙伴的跨学科方法可以深入了解其中的酶和物理化学过程。我们还期望通过对乳液性质和组成的影响的知识获得，可以开发数学模型来描述BioPE中的反应动力学，并帮助找到有效氧化官能化的最佳技术条件。该项目的成果可以从根本上有助于使生物催化氧化功能化可用于生物化学过程。

Functionalization with oxygen is a key operation in various organic chemical syntheses. With regard to environmental protection and sustainability, replacing the currently used highly toxic oxidizing agents such as chromates by hydrogen peroxide or molecular oxygen is highly desired. A variety of enzymes such as lipases and per- and monooxygenases catalyze these reactions under mild and selective conditions. However, due to the lack of an appropriate technology, that synchronizes both the specific features of oxyfunctionalization reactions and the specific properties of biocatalysts, bio-based oxyfunctionalization has hardly been adopted for synthesis yet. Based on the knowledge gained from previous joint projects, we here propose that bioactive Pickering emulsions (BioPEs) in a continuous membrane reactor could be a viable basis for such a technology. We suppose that both the formulation of the biocatalyst or its placement at the liquid-liquid interface, respectively, and the physical properties of the BioPE can be optimized to increase synthetic performance. Thus, this project systematically investigates the employment of BioPE in a continuous membrane reactor for the sustainable biocatalyzed oxyfunctionalization of organic compounds with differently complex biocatalysts (lipases, per- and monooxygenases), taking into account specific features of the catalytic systems, the reaction technology and their interplay. It addresses the fundamental question if, or possibly which biocatalyzed oxyfunctionalization benefits from implementation into Pickering emulsions, and will identify and optimize key parameters (e.g. drop size, interfacial area, biocatalyst load and location, substrate supply, phase composition) that determine the catalytic performance of the reaction system. The interdisciplinary approach with partners from biotechnology and engineering enables in-depth understanding of the enzymatic and physico-chemical processes within. We also expect that by knowledge gain on the influence of emulsion properties and composition a mathematical model can be developed to describe the reaction kinetics in BioPE and help finding the optimal technological conditions for efficient oxyfunctionalization. The project outcome can fundamentally contribute to make biocatalyzed oxyfunctionalization accessible for biochemical processes.