Characterizations of Two Bacterial Strains Showing High Keratinase Activities and Their Synergism in Feather Degradation

Abstract

On the basis of physiological and biochemical tests using API LAB II plus computer programe analysis, two feather-degrading bacteria, KUB-K0006 and KUB-K0082 were identified and classified as Bacillus licheniformis and B. pumilus. Synergistic action of crude enzyme fluids from KUB-K0006 (CFL) and KUB-K0082 (CFP) with the ratio of 5:1 showed higher amount of digested feather than the one obtained from CFP and CFL alone at 3.04 and 2 times respectively, while the ratio of 1:5 showed higher amount of amino acid released than the one obtained from CFP and CFL alone at 1.13 and 1.77 times . The addition of 5 times, CFL however created the values of %pepsin digestibility to be 1.4 and 1.2 times of the action of CFP and CFL alone . When the suitable amount of enzyme was studied, it was found that 500-1000 units of CFL:CFP, 5:1, hydrolyzing feather provided the percentage of pepsin digestibility to be more than 75. Comparing to the commercial enzyme allzyme BPD, the comparative equally % pepsin digestbility obtained showed no significantly difference when 1,000 units was used.