Keratinases from Streptomyces netropsis and Bacillus subtilis and Their Potential Use in the Chicken Feather Degrading

Feathers are the most prevalent agricultural waste generated by chicken farms, polluting environment and wasting protein resources as a result of accumulation large amounts feathers. Therefore, keratinase-producing microorganisms represent promising potential technique for degradation feather waste. Streptomyces netropsis A-ICA Bacillus subtilis ALICA, previously isolated from rhizosphere desert plants (Larrea tridentata Prosopis juliflora) respectively, were assessed their feather-degradation ability. Keratinase activity was optimized using various parameters, including incubation time, pH, temperature, concentration. The maximum keratinase S. B. ALICA (113.6 ± 5.1 135.6 4.1 U/mL) obtained at 5th 3rd day with initial pH 7.0 7.5 25 30 °C, 1% (w/v) feather, respectively. Under conditions, concentration soluble in hydrolysate reached 423.3 565.3 7.7 µg/mL, feathers weight loss 84 2 86± 1.5% highest disulphide bond reductase 10.7 0.4 1.96 1.1 U/mL, after five three days inoculation Furthermore, antioxidant evaluated DPPH radical-scavenging activity, which exhibited significant an IC50 value 0.8 0.6 mg/mL. 3D models detected keratinases both strains showed high similarity subtilisin family. Further, docking results clarified importance GSG VVVFTP domains beta-keratin, present study revealed keratinolytic degradation, have application may be exploited supplementary animal feed formulations.