Hydrolysis of triglycerides with cold-adapted lipase of Psychrobacter sp. S3 isolated from intertidal flat

Abstract

Lipase-producing bacteria (S3) were isolated from intertidal flat at Saemanguem. A isolated strain was identified as Psychrobacter species by physiological and fermentational characterization as well as 16S rRNA analysis. The strain was then named as Psychrobacter sp. S3. P. sp. S3 grew most rapidly at 30°C, but grew well even at 10°C and its lipase activity was most high when cultivated at 20°C. Lipase S3 had optimum temperature of 30°C for the hydrolysis of p-nitrophenyl caproate and had more than 80% activity even at 10°C. The activation energy was calculated to be 1.5 kcal/mol, which showed that it was a typical cold-adapted enzyme. It was an alkaline enzyme with optimum pH of 9.0≃9.5. It could hydrolyze various length of triglycerides. Among them, it hydrolyzed most rapidly C4, C14, C 16-length triglycerides. When added to tributyrin-agarose gel, lipase S3 hydrolyzed tributyrin most rapidly at 30 and 40°C, but it could hydrolyze well even at 4°C.