Properties and applications of keratin from the waste of animal-farming (review article)

The study aims to provide a modern overview of the properties of keratin-containing raw materials from animal waste among the research scientists over the past decades and to show the important role of keratin in science. This review examines the composition and types of keratin, the scope of application, the functions of keratin, distribution in animal husbandry and fish farming, as well as in mammals. It is important to note that keratin is widely used in biomedicine, tissue engineering, bioplastics, textiles, biocomposites in construction and building materials. This article reveals the physical and chemical properties and advantages of keratin, such as biodegradability, mechanical abilities, resistance to temperature conditions and thermal conductivity. Keratin can be synthesized from different raw materials, such as wool, hair, bird feathers, using different methods. The extraction method can be of several types: oxidative and reducing, as well as extraction by steam explosion. Extracted keratin has generated increased interest for its study and research for medical purposes, or rather the first innovative discoveries were made among cosmetics, coatings for medicines and fibers. Keratin extracted from animal waste represents a promising active biomolecule for biological and biomaterial applications. The exceptional properties that keratin transmits by virtue of its nature open up the possibility of replacing synthetic materials with biomaterials more compatible with humans and biodegradable, which can improve the overall economy of the closed cycle of agro-industrial complexes. 

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