Monday, July 25, 2011
Grand Ballroom, 5th fl (Sheraton New Orleans)
Feathers consist primarily of keratin and are generated in large quantities as a waste by-product in commercial poultry processing industries. The accumulation of feathers can result in environmental pollution and feather protein wastage. Traditional ways to degrade feathers such as alkali hydrolysis and steam pressure cooking may not only destroy the amino acids but also consume large amounts of energy. Biodegradation of feathers by keratinase from microorganisms may provide a viable alternative. Keratinase applications include the use of feather meal as feed supplements, nitrogen fertilizers, cosmetics, leather processing (tannery), fiber modification (textiles). The study of culture conditions is very important to optimize the enzyme production. The goal of this research was to verify the culture conditions in bioreactor to production keratinase by Bacillus amyloliquefaciens strains isolated from wastewater from a poultry industry. The experiments were performed in reactor (Bio Zeta Mini T), at agitation of 100, 150, 200, 250, 300 rpm, aeration (0.25, 0.5, 0.75, 1.0, 1.25 vvm), feather concentration [0.3, 1, 1.7, 2.4 (w/v)] and temperature (25, 30, 35, 40, 45ºC). Substrate azoqueratina was used to determine the keratinolytic activity. The results showed that higher keratinolytic activity was obtained at 150 rpm, 30°C, 1vvm and 1% feathers. The highest activity was obtained within 48 hours of culture (59.75 U/mL) with higher feathers degradation. The presence of amino acids in the fermented broth, such as cysteine, proline, serine, tyrosine and leucine was observed. According to the results we observed that the strain B. amyloliquefaciens has potential use in biotechnological processes.