Background: The hydrolysis of keratin wastes by microorganisms is considered a biotechnological alternative for recycling and valorization through keratinolytic microorganisms. Despite the resistant structure, keratin wastes can be efficiently degraded by various microorganisms, based on the secretion of keratinases, promising enzymes for several applications, including detergents, fertilizers, leather and textile industry. In an attempt to find keratinolytic microorganisms that can reach commercial exploitation as keratinases producers, the current work asses the dynamics of the keratins biodegradation by several keratinolytic fungal strains isolated from soil. The activity of fungal strains to degrade keratin substrates was evaluated based on SEM, FTRIR-ATR spectra and TGA analysis.

Results: SEM observations offered relevant information on interactions between microorganism and structural elements of hair strand. FTIR spectra by the bands at 1035-1075 cm^-1 assigned to sulfoxide bond appeared as a result of S-S bond breaking demonstrated the initiation of keratin biodegradation. According to TGA analysis, in second zone of thermal denaturation where occur the keratin degradation was obtained the highest weight loss of 71.10% for sample incubated with Fusarium sp 1A.

Conclusions: Among tested strains, Fusarium sp. 1A was found to be the most active in degradation process with the strongest denaturation of polypeptide chains. Since keratinolytic microorganisms and their enzymes keratinases represents a subject of scientific and economic interest due to their capability to hydrolyzed keratin, Fusarium sp. 1A was selected for further studies.