Production of alkaline protease from a haloalkaliphilic soil thermoactinomycete and its application in feather fibril disintegration

Proteases have found a wide application in several industrial processes, such as laundry detergents, protein recovery or solubilization, prion degradation, meat tenderizations, and in bating of hides and skins in leather industries. In the present study, a bacterial isolate, Thermoactinomyces sp.  RS1, isolated from soil sample was taken for enzyme production by submerged fermentation technology. The classical “one-variable-at-a-time approach” was employed. Optimum incubation time, pH and temperature were found to be 24 h; pH 9.0 and 55°C, respectively. The enzyme production was highest at salt concentration of 5%; inoculum of 4% and agitation rate of 150 rpm. RS1 could grow in the presence of all carbon sources employed and was highest with glucose. In the case of organic nitrogen sources, enzyme production was highest with peptone and in the case of inorganic nitrogen sources, enzyme production was highest in urea. Overall, 1.5 folds of production was achieved after optimization of all conditions of previously used culture media. Protease in the present study shows good feather degradation within short incubation time, presenting its utilization for poultry feed production. The study holds significance as only few reports are available on the alkaline proteases having keratinolytic property from haloalkaliphilic bacteria. Key words: Protease, feather disintegration, haloalkaliphilic isolate, thermoactinomyces, submerged fermentation.