Isolation and purification of lipase from Bacillus subtilis in oil mill.

ABSTRACT

In this study, the lipolytic Bacillus subtilis was isolated from the oil mill waste by Enrichment technique.The isolated colonies were screened on Tributyrin agar medium, colonies which produce the maximum clear zone of the particular organisms was used for further optimization studies. Among the 3 isolates Bacillus subtilis a single isolate was the subjected to solid state fermentation medium and the enzyme characteristics were studied with respect to pH, temperature and incubation period.The production and lipase activity were found maximum 0.45U/mL at pH, 0.45U/mL at temperature 37°C and 0.41U/mL at incubation period 48 hours. The lipase purification steps involved, 60% ammonium sulphate saturation and ion exchange chromatography with DEAE cellulose. To apparent homogeneity as evident by a single band of 62.2kDa on sodium dodecyl sulphate polyacrylamide gel electrophoresis. From the study it was concluded that the commercially important enzyme can be produced by submerged fermentation techniques using frequently available edible oil sources it can be used for the biodegradation of oil effluents.