Microbial production and industrial applications of keratinases: an overview.

Massive production of keratinaceous byproducts in the form of agricultural and industrial wastes throughout the world necessitates its justified utilization. Chemical treatment of keratin waste is proclaimed as an eco-destructive approach by various researchers since it generates secondary pollutants. Microbial degradation of keratin waste is an emerging and eco-friendly approach and offers dual benefits, i.e., treatment of recalcitrant pollutant (keratin) and procurement of a commercially important enzyme (keratinase). This review summarizes the potential utility of some bacterial and fungal species for the production of keratinase using a variety of keratinaceous wastes as growth substrates. The application of microbial keratinases in waste management; animal feed, detergent, and fertilizer manufacturing; and leather, cosmetic, and pharmaceutical industries is also abridged in this review.