Twenty-five isolates of protease-producing bacteria and fungi were isolated from salted fish and their proteolytic activity was determined after 4 days cultivation at 37 C on media contained 10% Naci. Eight isolates were belonging to Bacillus subtilis and two isolates as Bacillus licheniformis. 15 isolates of fungi including two different genera with five species were identified as three isolates of Penicillium chrysogenum, two isolates of Pinigricans, five isolates of P.bre vicompactum, two isolates of P.citrinum and three isolates of Aspergillus terreus. One isolate of Bacillus subtilis was chosen as the most promising protease producer. Optimal conditions for enzyme production by B. subtilis A05 was pH 8.0, 37°C, 4% (W/V) starch as carbon source and 2% (W/V) casein as nitrogen source. Ca and Mg stimulated enzyme synthesis. Maximal activity of the crude enzyme was at pH 8 and the optimal temperature was 60°C. The protease retained 63% of its original activity after 40 min at 80°C. Protease was stable in NaCl with 62% of the original activity being retained in 25% (W/V) Naci.
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