Optimization of protease production from Bacillus sp.

Protease can be used for large variety of functions and have important applications in biotechnology. In this research, four bacterial strains used isolated from different sources of the hot spring and were cultured in skim-milk agar plates. Four different strains have been isolated named as isolate ZA 1, ZA 2, 50 a and 50 b. The most productive microorganism to precede this research has been observed in the SMA. The strains that have higher productivity are the isolate strain ZA 2. Isolate strain ZA 2 have been identify as Bacillus lincheniformis strain ZA 2 from the previous proceeding by Ibrahim and Salleh (2010). The main aim of this research were optimizing the production of the thermophilic protease under different physical factors. The physical factors that have been tested are pH, temperature, agitation and inoculums size. Protease production was detected over a broad pH range from 6-10. However the B. licheniformis strain ZA 2 was found to produce alkaline protease at a maximum activity 32.39 U/ml at pH 8. Furthermore the protease production was detected from temperature range from 50 °C — 70 °C. The best temperature has been tested for the protease activity is 60.28 Wm! at 65 °C. Next are the protease production was detected over a broad agitation range from 0 200 rpm. At the end of the test, the maximum protease production is 66.92 Wm! at 100 rpm. Last but not lease the inoculums sizes that have been used to detect the protease production are from range 2% - 10%. The maximum enzyme activity 67.37 U/ml was detected at 8% of inoculums size.