Research and Development Center of Food Proteins, Guangdong Province Key Laboratory for Green Processing of Natural Products and Product Safety, Department of Food Science and Technology, South China University of Technology, Guangzhou 510641, P. R. China.
College of Food Science, Fujian Agriculture and Forestry University, Fuzhou 350002, P. R. China.
J Agric Food Chem. 2023 Aug 16;71(32):12289-12299. doi: 10.1021/acs.jafc.3c03856. Epub 2023 Aug 7.
Double emulsions hold great potential for various applications due to their compartmentalized internal structures. However, achieving their long-term physical stability remains a challenging task. Here, we present a simple one-step method for producing stable oil-in-water-in-oil (O/W/O) double emulsions using biocompatible gliadin/ethyl cellulose complex particles as the sole stabilizer. The resulting O/W/O systems serve as effective platforms for encapsulating enzymes and as templates for synthesizing porous microspheres. We investigated the impact of particle concentration and water fraction on the properties of Pickering O/W/O emulsions. Our results demonstrate that the number and volume of inner oil droplets increased proportionally with both the water fraction and particle concentration after a 60-day storage period. Moreover, the catalytic reaction rate of the encapsulated lipase within the double emulsion exhibited a significant acceleration, achieving a substrate conversion of 80.9% within 15 min. Remarkably, the encapsulated enzyme showed excellent recyclability, enabling up to 10 cycles of reuse. Additionally, by utilizing the O/W/O systems as templates, we successfully obtained porous microspheres whose size can be controlled by the outer water droplet. These findings have significant implications for the future design of Pickering complex emulsion-based systems, opening avenues for extensive applications in pharmaceuticals, food, cosmetics, material synthesis, and (bio)catalysis.
双乳液由于其分隔的内部结构，具有广泛的应用潜力。然而，实现其长期的物理稳定性仍然是一个具有挑战性的任务。在这里，我们提出了一种简单的一步法，使用生物相容性的麦醇溶蛋白/乙基纤维素复合颗粒作为唯一的稳定剂来制备稳定的油包水包油（O/W/O）双乳液。所得的 O/W/O 体系可用作封装酶的有效平台和合成多孔微球的模板。我们研究了颗粒浓度和水相分数对 Pickering O/W/O 乳液性质的影响。我们的结果表明，在 60 天的储存期后，内油滴的数量和体积与水相分数和颗粒浓度成比例增加。此外，双乳液中包封脂肪酶的催化反应速率显著加快，在 15 分钟内达到 80.9%的底物转化率。值得注意的是，包封酶表现出优异的可重复使用性，可重复使用多达 10 次。此外，通过将 O/W/O 体系用作模板，我们成功地获得了多孔微球，其尺寸可以通过外层水相来控制。这些发现对于未来设计基于 Pickering 复合乳液的系统具有重要意义，为在制药、食品、化妆品、材料合成和（生物）催化等领域的广泛应用开辟了道路。
