Isolation, Optimization, and Molecular Characterization of a Lipase Producing Bacterium from Oil Contaminated Soils

Abstract

Lipases have many applications in biotechnology, thanks to their ability of acylglycerides hydrolysis. They alsp possess the unique feature of acting at the lipid-water interface, which distinguishes them from esterases. Commercially useful lipases are produced by microorganisms with the extracellular lipase being produced by many bacteria including Pseudomonas. The greatest production of lipase takes place under optimum conditions such as appropriate temperature, suitable carbon, nitrogen sources, etc. This study tries to collect lipase-producing bacteria from the soil of oil-extraction factories and identify isolated bacteria, while creating optimum conditions for lipase production by bacteria. Having collected three soil samples from an oil extraction factory, lipase-producing bacteria have been identified, based on biochemical and morphological tests. Finally the optimal conditions for lipase production as well as molecular analysis has been evaluated. During the study, among the different bacteria, the strain to produce highest lipase has been selected. It has been found out that the optimal conditions for lipase production by this strain is as follows: 48 hours of incubation; incubation temperature of 37 °C; pH of 7; agitation speed of 150 rpm; peptone extract as the nitrogen source; and olive oil as a carbon source. A lipase-producing bacterium has been identified based on morphological, physiological, and biochemical characteristics as well as 16S rRNA analysis, identified as Pseudomonas spp.