The rapid expansion of the livestock and poultry industry has led to a considerable increase in slaughter byproducts; however, exploring their potential applications still needs to be improved. These underutilized byproducts, which include nails, hides, skins, and bones, represent a significant loss of valuable biological resources. Among these materials, keratin has garnered considerable attention due to its unique properties as a natural biopolymer. Keratin exhibits outstanding mechanical properties and biocompatibility and has attracted increasing attention for its recovery and conversion into relevant application materials. However, natural keratin typically has a high sulfur content, complex 3D structure, and abundant hydrogen and disulfide bonds, which cause challenges in application. Current extraction for keratin includes physical, chemical, biological, and hybrid approaches. Combining multiple methods synergistically enhances protein extraction efficiency and purity, and facilitates the exploration of structure and functional properties. This review encompasses the structural characteristics, properties, extraction methods, and research progress related to keratin. The preparation and application of keratin composite materials in different forms, such as fibers, films, hydrogels, and scaffolds, are illustrated. Applications in several fields, including biomedicine, flexible electronic components, environmental materials and food packaging are discussed. Hopefully, this paper will provide a comprehensive understanding and guidance for further development and application of keratin materials.

中文翻译：

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释放角蛋白的潜力：从提取和结构特性到跨学科应用的全面探索


畜禽业的快速扩张导致屠宰副产品大幅增加;然而，探索它们的潜在应用仍然需要改进。这些未充分利用的副产品，包括指甲、兽皮、皮肤和骨骼，代表着宝贵生物资源的重大损失。在这些材料中，角蛋白因其作为天然生物聚合物的独特特性而受到广泛关注。角蛋白表现出优异的机械性能和生物相容性，并因其回收和转化为相关应用材料而受到越来越多的关注。然而，天然角蛋白通常具有高硫含量、复杂的 3D 结构以及丰富的氢键和二硫键，这在应用上带来了挑战。目前角蛋白的提取包括物理、化学、生物和混合方法。结合多种方法协同提高蛋白质提取效率和纯度，并促进结构和功能特性的探索。本文综述了角蛋白的结构特性、性质、提取方法和研究进展。说明了不同形式的角蛋白复合材料的制备和应用，例如纤维、薄膜、水凝胶和支架。讨论了多个领域的应用，包括生物医学、柔性电子元件、环境材料和食品包装。希望本文能为角蛋白材料的进一步开发和应用提供全面的理解和指导。