Protease-producing microorganisms inhabiting salted fish (Moloha) with special reference to protease activity of Bacillus subtilis

M. H. Abd-Alla, S. A. Omar, M. A. El-Nagdy


The investigation was designed to isolate and identify the proteolytic microorganisms inhabiting salted fish. Bacillus subtilis was chosen as the most promising protease producer. Some properties of the crude protease are presented, the effect of metal ions on protease production has been studied. It was shown that Ca2+ and Mg2+ stimulated, while Co2+ , Zn2+ and Cu2+ inhibited the enzyme production. The effect of temperature and pH and salt tolerance have also been studied. Protease activity was stable in 25% NaCl. The favourable characteristics of the enzyme might have extensive application in laundry detergents and in tanning industry.


bacteria; fungi; extracellular proteases; Bacillus subtilis; proteolytic activity

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