Keratinase Producing Bacteria: A Promising Approach for Poultry Waste Management

A large amount of feather is produced each year in the poultry industries which is buried in landfill or burned in the power plant generator. Feathers are purified keratinous proteins that can be degraded by bacteria and fungi. The aim of this study was to isolate and identify keratinase producing bacteria from the feather waste dumping sites around Gorgan district, Golestan province, Iran. Soil samples were collected from six poultry farms and slaughterhouses. The keratinolytic bacteria were isolated and identified based on feather and keratin degradation in feather meal broth and keratin agar. Isolates that showed more keratinolytic activity were identified using morphological, biochemical, and molecular tests. Then, the effect of pH and temperature was examined on the growth of the isolates. Based on the results, keratinase-producing isolates belonged to the Bacillus genus, among the isolates, the most keratinolytic activity was related to Bacillus megaterium strain SR7 and it showed the best growth at pH 6.8 and 37°C in feather meal broth and keratin agar. The results of the present study were consistent with the results of many similar studies and found that Bacillus strains are important producers of keratinase enzyme and therefore promising organisms for the management of chicken feather wastes through efficient biodegradation.