Extracellular Lipase production and optimization in a native moderately halophilic bacterium of Iran

Extracellular lipase production was studied in a Gram-negative moderately halophilic bacterial strain that was isolated from Garmsar river and temporary identified as Salinivibrio sp. ZG13-2 by phenotypic characterization. Lipase activity and stability were assayed with Paranitrophenyl butyrate as a substrate in different pH values, salts and temperatures. The optimum conditions for lipase secretion were: pH8, temperature 35°C, aeration 150 rpm, NaCl 1M and olive oil 2%. Carbohydrates (glucose, galactose, fructose and starch) and glycerol didn’t induce lipase production. The maximum lipase activity was at NaCl 1M, pH 7.5 and at 50 C and CaCl2 0.01M. Lipase Enzyme was stable at pH 7.5-8 for 4 hours and retaining 90% activity in 80 C for 30 minuets. Different concentrations of salts have no effect on stability.