keratin waste: sustainable resources for a greener future

Keratin is the third most common polymer after cellulose and chitin؛ feathers are approximately 90% β-keratin, an extremely tough structural protein characterized by a unique fibrous structure. managing keratin waste is a significant environmental challenge. about 24 million chickens are killed annually, producing 8.5 billion tons of feathers. animal proteins that decompose very slowly are typically discarded by site burning or landfilling, which can negatively affect the environment due to carbon dioxide emissions and energy loss. developing an environmentally friendly way to address these persistent keratin residues is critical. recycling waste keratin can produce an abundant quantity of protein and amino acids. it can provide an alternative source of protein, which can be an economical way to supply protein for many purposes, including animal feed production. nonetheless, keratin is too poorly digestible to be recycled easily. however, bacteria that produce keratinase also enable feather degradation, presenting a much more sustainable and environmentally friendly alternative. additionally, microbial-derived keratinases can degrade feathers to produce digestible peptides. keratinases are known to be produced by microorganisms, including bacilli, fungi, and actinomycetes. although initial steps towards large-scale microbial keratin biodegradation are promising, several obstacles remain to be met. these challenges include optimizing fermentation conditions, enhancing enzyme stability, and minimizing operational costs. metabolic and genetic strategies can be employed to obtain robust microbial strains that exhibit increased keratinase production. microbial keratinases show promising applications in waste management and resource recovery by biodegradation of keratin wastes. ongoing research to optimize microbial strains and enzymatic processes is crucial for developing cost-effective bioconversion pathways that reduce the environmental impact of keratin waste and enhance animal feed. microbial keratinases enzymatic degradation of keratin waste can significantly improve resource efficiency and management. this reduces the environmental impact of keratin waste and creates more opportunities for producing animal feed.