School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
School of Chemistry and Chemical Engineering, Yangzhou University, Yangzhou 225002, China.
J Colloid Interface Sci. 2024 Jun;663:591-600. doi: 10.1016/j.jcis.2024.02.142. Epub 2024 Feb 19.
The key feature of living cells is multicompartmentalization for enzymatic reactions. Artificial cell-like multicompartments with micro domains are appealing to mimic the biological counterparts. In addition, establishing a sustainable, efficient, and controllable reaction system for enzymatic hydrolysis is imperative for the production of natural fatty acids from animal and plant-based fats.
Reverse Janus emulsion microreactors, i.e. (W + W)/O, is constructed through directly using natural fats as continuous phase and aqueous two-phase solutions (ATPS) as inner phases. Enzyme is confined in the compartmented aqueous droplets dominated by the salt of NaSO and polyethylene glycol (PEG). Enzyme catalyzed ester hydrolysis employed as a model reaction is performed under the conditions of agitation-free and mild temperature. Regulation of reaction kinetics is investigated by diverse droplet topology, composition of inner ATPS, and on-demand emulsification.
Excellent enzymatic activity toward hydrolysis of plant and animal oils achieves 88.5 % conversion after 3 h. Compartmented micro domains contribute to condense and organize the enzymes spatially. Timely removal of the products away from reaction sites of oil/water interface "pushed" the reaction forward. Distribution and transfer of enzyme in two aqueous lobes provide extra freedom in the regulation of hydrolysis kinetics, with equilibrium conversion controlled freely from 14.5 % to 88.5 %. Reversible "open" and "shut" of hydrolysis is acheived by on-demand emulsification and spontaneous demulsification. This paper paves the way to advancing progress in compartmentalized emulsion as a sustainable and high-efficiency platform for biocatalytic applications.
活细胞的主要特征是酶反应的多区室化。具有微观区室的人工类细胞多区室结构吸引人们去模拟生物对应物。此外，建立一个可持续的、高效的、可控的酶水解反应系统对于从动植物脂肪中生产天然脂肪酸是至关重要的。
通过直接将天然脂肪作为连续相和双水相溶液（ATPS）作为内相来构建反向 Janus 乳液微反应器，即（W+W）/O。酶被限制在由 NaSO 和聚乙二醇（PEG）盐主导的分隔水相液滴中。在无搅拌和温和温度的条件下，进行酶催化酯水解作为模型反应。通过不同的液滴拓扑结构、内相 ATPS 的组成以及按需乳化来研究反应动力学的调节。
植物和动物油脂的水解酶活性非常高，经过 3 小时后转化率达到 88.5%。分隔的微区有助于将酶空间上凝聚和组织起来。及时将产物从油水界面的反应位点中移除“推动”了反应的进行。酶在两个水相叶中的分布和转移为水解动力学的调节提供了额外的自由度，平衡转化率可从 14.5%自由控制到 88.5%。通过按需乳化和自发破乳实现水解的可逆“开启”和“关闭”。本文为推进分隔乳液作为生物催化应用的可持续和高效平台方面的进展铺平了道路。
