Extraction and characterization of keratin from bovine hoof: A potential material for biomedical applications

Keratin from the hoof is a less explored source for making valuable products. In this paper we present the extraction of pure keratin from bovine hooves and characterized them to better address the possible exploitation of this bio-resource as an alternative material for tissue engineering applications. The keratin protein from the pulverized hooves was extracted by reduction, which was observed to be pure, and two polypeptide chains of molecular weight in the range of 45-50 and 55-60 KDa were determined using SDS-PAGE assay. FTIR analysis complementing circular dichroism (CD) data, established that hoof keratin predominantly adopted α-helical conformation with admixture of β-sheet. The keratin was shown to have appreciably high denaturation temperature (215°C) as indicated by differential scanning calorimetric (DSC) analysis. Thermogravimetric analysis (TGA) also showed the retention of 50% of the original weight of the sample even at a temperature of 346°C. The keratin from the hoof had been observed to be biocompatible when analyzed with MTT assay using fibroblast cells, showing more than 90% cell viability. Hence, hoof keratin would be useful for high value biomedical applications.