Characterization and Optimization of Thermostable Alkaline Protease Producing Pseudomonas aeruginosa from Tannery effluent

Proteases are being an industrial candidate, which are widely used in bakery, beverages and detergent industry. The leather industry deals with proteinous skin material for the conversion of leather and this generates huge amount of solid and liquid wastes giving rise to pollution that need to be overcome by introducing sustainable cleaner technologies. This study is a search for potential protease producing strain from tannery industry effluent. Different isolates were screened for the ability to produce protease. Then the potential organisms were tested using various biochemical tests, which lead to their identification as Pseudomonas aeruginosa. The effects of various environmental factors on the production of protease were studied. The organism showed the maximum growth and enzyme production at pH 8.0 and temperature at 40oC. The protease enzyme was purified using ammonium sulphate (70%) precipitation. Further purification was done by membrane dialysis. The crude and partially purified protease was preliminary characterized and used for dehairing process and destaining process at lab scale level in which the dialyzed fraction showed comparatively significant effect. The protease obtained from these strains showed good stability and activity in pH ranges of 8 and at temperature of 40⁰C suggesting the possibility of using the enzyme in leather, detergent, food tenderization and many such industries.