热变性牛血清白蛋白对三种活性物质的复合和保护作用

本文通过竞争实验证明热变性牛血清白蛋白(hBSA)同时结合α-生育酚、白藜芦醇和表没食子儿茶素没食子酸酯(EGCG)的可能性,通过结构稳定性和抗氧化稳定性实验表征蛋白对活性物质的保护情况。结果表明hBSA能同时结合三种物质,并且在复合物的形成过程中不存在竞争行为。储藏48 h后,游离态α-生育酚、白藜芦醇、EGCG残留率分别为48%、68%、0%,hBSA-EGCG-α-生育酚-白藜芦醇复合物中残留率分别为91%、90%、15%;储藏288 h后,游离态的α-生育酚、白藜芦醇、EGCG对ABTS自由基的清除能力分别减少了6%、10%、31%,hBSA-EGCG-α-生育酚-白藜芦醇复合物仅减少了13%。因此,hBSA是同时负载三种活性物质的良好载体。研究结果将为蛋白类共包埋载体的开发提供更多参考依据。     

Encapsulation and protection of resveratrol in kafirin and milk protein nanoparticles

Food proteins have been widely used as carrier materials for the encapsulation of bioactive ingredients. Combination with hydro-soluble proteins provides better properties to prolamin-based particles. Kafirin obtained from sorghum belongs to cereal prolamin proteins. In this study, kafirin nanoparticles in the absence and presence of beta-lactoglobulin (β-Lg) or casein were prepared for the encapsulation and protection of resveratrol. The particles stabilised by 2% β-Lg or 0.2% casein were the smallest in size. Encapsulation efficiency of resveratrol was between 67% and 76% in kafirin/milk protein particles and the highest in kafirin/casein particles. Encapsulation in kafirin/milk protein particles improved DPPH˙ scavenging capacity of resveratrol but decreased its ABTS˙⁺ scavenging capacity. Stability of resveratrol ranked in order kafirin/casein > kafirin/β-Lg ~ kafirin.     

益生菌微胶囊的制备及其在食品中应用的研究进展

益生菌对人体健康有益而被广泛应用于食品领域,但其易受温度、氧气、湿度、压力、胃酸和胆汁盐等不良环境因素影响。为使益生菌在加工、储藏、消化过程中保持高存活率,人们利用不同的微胶囊技术对益生菌进行包埋和保护。益生菌微胶囊技术通过创建一种物理屏障来提高益生菌对不良环境的抗性力,减少保护基质中益生菌的损伤,从而使其到达目标部位顺利释放并发挥作用。文章概述了益生菌的起源、种类及益生功效,重点总结了益生菌微胶囊常用制备方法的基本原理及优缺点,包括挤压法、乳化法、喷雾干燥法、冷冻干燥法、喷雾冷却法、复凝聚法、静电纺丝、电喷雾和撞击气溶胶法,进而重点讨论了益生菌微胶囊技术在乳制品、肉制品、非乳饮料及焙烤制品等食品中的应用优势和可能性。虽然众多研究进行体外模拟消化,但仍存在一定局限性,对于现有的问题,未来仍然需要通过扩大包埋方法、开展体内实验、建立系统性数据库等方法来满足益生菌食品的工业化生产需求,以为开发新型益生菌食品提供理论借鉴和参考。     

Antioxidant activity and stability of α-tocopherol,resveratrol and epigallocatechin-3-gallate in mixture and complexation with bovine serum albumin

Ligand-binding proteins were proposed as ideal carriers for the co-encapsulation of bioactive compounds. Multiple compounds co-encapsulated in food formulation may give rise to different effects on bioactivity and stability. The protein effect on the interplay between bioactive compounds was investigated for selecting suitable co-encapsulation strategy. α-Tocopherol, resveratrol and epigallocatechin-3-gallate (EGCG), as model compounds, interacted with bovine serum albumin (BSA) to form tri-ligand complexes when added in the sequence. For ferric-reducing antioxidant power, the mixtures of α-tocopherol and resveratrol,α-tocopherol and EGCG, resveratrol and EGCG were respectively additive, antagonistic and synergistic, while their ternary mixture were antagonistic. For ABTS+ scavenging capacity, all pairs were antagonistic. BSA improved FRAP of α-tocopherol, resveratrol and EGCG mixture but decreased their ABTS inhibition. Although structural stability and antioxidant activity of resveratrol decreased when alone interacted with BSA, they were improved when α-tocopherol and EGCG were co-presented. Mixing the antioxidants improved their stability and the complexation with BSA can further stabilise them. BSA could thus be a suitable carrier for co-encapsulation/protection of α-tocopherol, resveratrol and EGCG in functional foods.     

A comprehensive review of protein-based carriers with simple structures for the co-encapsulation of bioactive agents

The rational design and fabrication of edible codelivery carriers are important to develop functional foods fortified with a plurality of bioactive agents, which may produce synergistic effects in increasing bioactivity and functionality to target specific health benefits. Food proteins possess considerable functional attributes that make them suitable for the delivery of a single bioactive agent in a wide range of platforms. Among the different types of protein-based carriers, protein–ligand nanocomplexes, micro/nanoparticles, and oil-in-water (O/W) emulsions have increasingly attracted attention in the codelivery of multiple bioactive agents, due to the simple and convenient preparation procedure, high stability, matrix compatibility, and dosage flexibility. However, the successful codelivery of bioactive agents with diverse physicochemical properties by using these simple-structure carriers is a daunting task. In this review, some effective strategies such as combined functional properties of proteins, self-assembly, composite, layer-by-layer, and interfacial engineering are introduced to redesign the carrier structure and explore the encapsulation of multiple bioactive agents. It then highlights success stories and challenges in the co-encapsulation of multiple bioactive agents within protein-based carriers with a simple structure. The partition, protection, and release of bioactive agents in these protein-based codelivery carriers are considered and discussed. Finally, safety and application as well as challenges of co-encapsulated bioactive agents in the food industry are also discussed. This work provides a state-of-the-art overview of protein-based particles and O/W emulsions in co-encapsulating bioactive agents, which is essential for the design and development of novel functional foods containing multiple bioactive agents.