keratinisch

Keratinisch is a German adjective derived from the noun keratin, which itself comes from the Greek word keratin, meaning “horn.” In a biological context keratinisch or keratinous describes tissues, structures, or materials that are composed mainly of keratin, a fibrous structural protein. Keratin is one of the most abundant proteins in the animal kingdom and is particularly prominent in organisms that possess a protective outer covering, such as birds, mammals, reptiles, fish, and invertebrates.

The keratinous integument of mammals consists of several layers. The outermost, epidermal layer contains keratinocytes that gradually fill with keratin and die, forming a tough, water‑resistant barrier. In birds, the feathers are made of feather keratin, which provides both strength and flexibility. Reptiles and fish have keratinous scales that shield their bodies. Insects’ exoskeletons and the claws, wings, and mandibles of many arthropods are also composed of all‑antoine keratin. In higher plants, trichomes and seeds may contain keratinous material, though true keratin is unique to the animal kingdom. Some algae have a keratinous coating that improves buoyancy.

Keratin, being insoluble and highly resilient, can be processed into many durable fibers. This property below is exploited by the textile industry, where wool, hair, and feather fibers are spun into yarn for clothing. Keratin also serves structural roles in engineering materials such as Cordura, or it is incorporated into biodegradable composites. Keratinous waste from poultry and other animal processing is increasingly explored as a source of renewable fibers and composite materials.

Research into keratin biology and its mechanical properties has implications for biomedical applications. Keratin‑based scaffolds are being studied for niche replacements in tissue engineering, while studies of keratin gene mutations illuminate inherited hair, skin, and nail disorders.