Effect of activators and inhibitors on extracellular thermostable alkaline protease isolated from Bacillus subtilis obtained from eastern province of Saudi Arabia

Alkaline proteases need some ions to achieve highest activity. These metallic ions help in, enzyme stability and activity through its thermal stability at high degrees. This protects the enzyme from being destroyed by heat. The results show that the ideal condition for enzyme activity was, using Mn2+ ions as the activator with 1112.5 U/ml activity, while MgSO4.7H2O has  lower effectiveness of an enzyme activity 247.5 U/ml. Benzene was the best solvent (867.5 U/ml), however ethylene glycol extract had lower solvents on enzyme activity (530 U/ml). KMnO4 has the best inhibitor with enzyme activity of 1325 U/ml, while ethylenediaminetetraacetate (EDTA) has the most effective inhibitor enzyme activity with 575 U/ml. Traditional methods in leather industries are based on using H2S and other chemicals, which are considered as ways of pollution and threaten the environmental health. So, biological treatment using protease enzyme is environmentally safe and help to ease manipulation, less byproducts and wastes. Alkaline protease is used in soaking leather, incubate at 50° C for different periods then wash and hair remove by distaining processes. The enzyme control remove hair for 30 min, its activity decreased for a period of 180 min making the enzyme potentially suitable for biotechnological applications. Key words: Alkaline protease, Bacillus subtilis, de-hairing, leather, enzyme stability.