Phytokeratin

Keratin is a fibrous structural protein and major component of hair, horns, claws, hooves, feather, wool, hoof and outer layer of skin. These keratinous materials are formed by cells filled with keratin and are considered ‘dead tissue’. Keratin acts both as an external protective protein & internal structural protein in the cortex. It is insoluble in water and organic solvents. Keratin can be derived from the human and animal sources by the advancement in extraction, purification and characterization process. It consists of highly repetitive amino acid sequences which result in formation of various homogeneous secondary structures. Keratin has been processed in oxidized and reduced forms in term of keratose and kerateine which shows strong mucoadhesive properties in drug delivery systems .It can also be processed as keratin hydrolysate by using acid, alkali and enzyme. Especially for hair care products, skin treatment and harsh products such as detergents, shampoos, conditioners etc. As it does not contain any harmful effect, it can be used to produce variety of cosmetics and pharmaceutical products. In addition, extracted keratins are capable of forming self-assembled structures that regulate cellular recognition and behavior. These qualities of keratin led to the development of biomaterials with applications in wound healing, drug delivery, target release action, tissue engineering, trauma and medical devices. This review discusses the natural sources of keratin and their derivatives and application of keratin biomaterials in pharmaceutics and cosmetics.