Characterization of Thermostable Keratinase from Bacillus sp.
P.J Lakshmi and V. V. Lakshmi
Abstract
Keratinase enzymes produced by two improved strains, Bacillus subtilis (MBF20) and Bacillus cereus (MBF45) were characterized to evaluate the application potential of the produced enzyme. Study of the physico-chemical characters of the enzyme showed that the isolated keratinase enzymes belonging to serine protease group were significantly stable at refrigerated conditions retaining >90% activity till one month while the activity reduced to 50% after two months. Further, the enzyme was active up to 48 hours at room temperature indicating that the enzyme had significantly higher stability than most of the reported keratinase enzymes. The enzyme was also themo-tolerant exhibiting optimum activity at 55°C though its activity range was between 28°C - 55°C. With optimum activity at alkaline pH of 8.5 and only marginal inhibition in presence of surfactants, organic solvents and considerable enhancement of activity in presence of reducing agents, the scope and versatility of the application potential of the isolated keratinase enzymes is significantly high.