Biochemical and genetically identification of solvent tolerant novel Bacillus subtilis Pa2.

A total of 25 isolates originating from hydrocarbon contaminated soil samples were successfully isolated via direct plating method using different growth medium. Eight isolates demonstrated high enzymatic potential (lipase, protease and amylase). Out of the total isolates, 86% isolates showed hydrocarbon degradation efficiency. These isolates were screened for lipolytic activity using tributyrine as substrate. Isolate Pa2 was found to produce the highest lipase yield on solid medium and later identified as Bacillus subtilis by biochemical test and 16s ribosomal RNA sequence. Stability studies in various organic solvents at 20% (v/v) showed that lipase from B. subtilis Pa2 was stable under different solvents like acetone, hexane and benzene. However, the activity was greatly reduced in ethylalcohol.