Abstract Vitamin A (VA) is an essential nutrient needed in small amounts by humans and supports a wide range of biological actions. Retinol, the most common and most biologically active form of VA has also been found to inhibit peroxidation processes in membranes and it has been widely used as an ingredient with pharmaceutical and nutritional applications. VA is a lipophilic molecule, sensitive to air, oxidizing agents, ultraviolet light and low pH levels. For these reasons, it is necessary for VA to be protected against oxidation. Another disadvantage in the application of VA is its low solubility in aqueous media. Both issues (sensitivity and solubility) can be solved by employing encapsulation techniques. Liposomes can efficiently encapsulate lipid-soluble materials, such as VA. The encapsulated materials are protected from environmental and chemical changes. A new liposome/β-lactoglobulin formulation has been developed as a stable delivery system for VA. The aim of this study was the encapsulation of VA into β-lactoglobulin–liposome complexes, recently developed in our laboratory. The in vivo bioavailability characterization of VA was tested after administration in laboratory animals (mice). In this report, we demonstrate that VA could be efficiently entrapped and delivered in a phospholipid–sterol–protein membrane resembling system, a newly synthesized promising carrier. Based on this finding, the phospholipid–sterol–protein membrane resembling system may be one of the promising approaches to enhance VA absorption and to overcome the formulation difficulties associated with lipophilic means. The carrier system described here has huge potential in food fortification applications to treat VA deficiency.

中文翻译：

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脂质体-蛋白质递送系统中维生素 A 包封的体外和体内评估

摘要 维生素 A (VA) 是人体必需的少量必需营养素，支持多种生物作用。视黄醇是最常见和最具生物活性的 VA 形式，也被发现可抑制膜中的过氧化过程，并已广泛用作药物和营养应用的成分。VA 是亲脂性分子，对空气、氧化剂、紫外线和低 pH 值敏感。由于这些原因，必须防止 VA 氧化。VA 应用的另一个缺点是其在水性介质中的溶解度低。这两个问题（灵敏度和溶解度）都可以通过采用封装技术来解决。脂质体可以有效地包裹脂溶性物质，如 VA。封装的材料免受环境和化学变化的影响。已开发出一种新的脂质体/β-乳球蛋白制剂作为 VA 的稳定递送系统。本研究的目的是将 VA 封装到我们实验室最近开发的 β-乳球蛋白-脂质体复合物中。在实验室动物（小鼠）中给药后，测试了 VA 的体内生物利用度特征。在这份报告中，我们证明了 VA 可以被有效地包裹和递送在类似于磷脂-甾醇-蛋白质膜的系统中，这是一种新合成的有前途的载体。基于这一发现，磷脂-甾醇-蛋白质膜类似系统可能是增强 VA 吸收和克服与亲脂性手段相关的制剂困难的有前途的方法之一。