Isolation and Identification of Protease Enzyme Producing Bacillus subtilis from Soil

Abstract

Bacillus subtilis is commonly recovered from water, soil, air and decomposing plant residue. But the main habitat of B. subtilis is soil and a long term survival is expected to occur in soil. In this study twenty samples of soil were collected from different industrial areas of Lahore. These soil samples were used to analyze the presence of microorganisms in it. Bacteria were grown on the specific medium for the colony identification. Then Biochemical test was performed to isolate and identify B. subtilis from the soil samples. In the present study, Bacillus species were found to be abundant in our soil samples. The bacteria isolated from the soil were rod shaped gram positive bacteria that form spores under stress conditions. The spores were appeared to be rounded and green in color inside the cell. Positive zone formation test confirmed the presence of B. subtilis. The protease enzyme was produced by B. subtilis in large quantities during vegetative growth. It was found that absorbance reached to its maximum value at 5µg/ml concentration of protease enzyme. The maximum values of absorbance were 0.45 and 0.5 at 550nm. It was concluded from the above results that soil is the main habitat of many microorganisms and among these microorganisms Bacillus subtilis was found to produce protease enzyme.