Aboudzadeh M Ali, Mehravar Ehsan, Fernandez Mercedes, Lezama Luis, Tomovska Radmila
POLYMAT, University of the Basque Country, UPV/EHU, Joxe Mari Korta Center, Avda. Tolosa 72, 20018 Donostia-San Sebastián, Spain.
Departamento de Química Inorgánica, Universidad del País Vasco UPV/EHU, B° Sarriena, 48970 Leioa, Spain.
ACS Omega. 2018 Sep 11;3(9):10999-11008. doi: 10.1021/acsomega.8b01272. eCollection 2018 Sep 30.
Encapsulation of active agents, such as vitamins and antioxidants, is one of the possibilities that allow their incorporation in beverages, food, or in pharmaceutical products. Simultaneously, encapsulation protects these active agents from oxidation, producing more stable active compounds. Formation of nanodroplets by spontaneously formed microemulsion (ME) offers, on one hand, a low-energy technology of encapsulation and, on the other hand, because of a small size of the droplets, it assures long-term stability even in harsher environments. In this study, oil-in-water MEs allowed the low-energy encapsulation of α-tocopherol (αToc) into an aqueous medium with the aid of fully food-grade ingredients, using isoamyl acetate as the dispersed oil phase, which was selected between three different types of oils. Both cosurfactant-free and cosurfactant-holder ME systems were formulated, in which Tween 20 and glycerol were employed as the surfactant and the cosurfactant, respectively. The ME monophasic area was determined through the construction of pseudoternary phase diagrams. The encapsulated αToc within 10-20 nm nanocapsules showed radical scavenging activity dependent on the encapsulated amount of αToc, as it was demonstrated by electron paramagnetic resonance spectroscopy. The radical scavenging activity slightly increased within the time investigated, indicating a slow release of the active compound from the nanodroplets, which is a promising result for their application, especially in pharmaceuticals.
封装活性剂，如维生素和抗氧化剂，是使其能够被添加到饮料、食品或药品中的一种可行方法。同时，封装可保护这些活性剂不被氧化，从而产生更稳定的活性化合物。通过自发形成的微乳液（ME）形成纳米液滴，一方面提供了一种低能量的封装技术，另一方面，由于液滴尺寸小，即使在更恶劣的环境中也能确保长期稳定性。在本研究中，水包油型微乳液借助完全食品级成分，以乙酸异戊酯作为分散油相（从三种不同类型的油中选择），实现了α-生育酚（αToc）在水介质中的低能量封装。制备了无共表面活性剂和含共表面活性剂的微乳液体系，其中分别使用吐温20和甘油作为表面活性剂和共表面活性剂。通过构建拟三元相图确定微乳液单相区。电子顺磁共振光谱表明，封装在10 - 20纳米纳米胶囊中的αToc表现出自由基清除活性，该活性取决于αToc的封装量。在所研究的时间内，自由基清除活性略有增加，表明活性化合物从纳米液滴中缓慢释放，这对于它们的应用来说是一个有前景的结果，尤其是在制药领域。
