Local isolate of Bacillus stearothermophilus producing alkaline phosphatase activity by two fermentation systems

Abstract EN

From soil samples in different region of Iraqi-Kurdistan, thirty-one isolates of Bacillus spp.

were isolated and identified in all samples according to morphology of colonies, cells and their growth at 55°c.

Using high temperature 75°c and some biochemical tests, only seven isolates were diagnosed as B.

stearothermophilus.

The isolate no.

18 was selected based on its high activity of enzymes (amylases & proteases).

Using two fermentation systems (liquid state & solid state fermentation), the isolate no.18 was examined for production of alkaline phosphatase (AP) enzyme activity.

The liquid state fermentation method for this isolate gave a 4.9 un it / ml enzyme activity at optimum pH and 5.8 unit / mg protein specific activity, whereas the solid state fermentation (wheat bran) gave 11.32 unit / ml enzyme activity and 7.48 unit/mg protein specific activity.

Results revealed high activity of alkaline phosphatase screening from local isolate of Bacillus stearothermophilus using wheat bran in solid state fermentation.