Production of lipase by the deep-sea bacterium Idiomarina zobellii; Identification of effective factors and optimization of production process

Introduction: In this study, the deepsea bacterium, Idiomarina zobellii, was used as a new source for the production of lipase. Lipases from halophilic bacteria are attractive for use in diverse industrial and biotechnological applications. Materials and methods: The optimal temperature and pH for the activity of I. zobellii lipase was determined using different temperature and pH ranging from 30-60 °C and 711, respectively. The growth conditions influencing lipase production were determined using twolevel fractional factorial Plackett–Burman design. The optimum levels of effective factors for production process were determined by using the response surface central composite design. Results: The optimum temperature and pH of I. zobellii lipase in the crude mixture were 78 and 50 °C, respectively. Among the screened 10 factors, MgCl2, yeast extract, sodium bicarbonate, ammonium nitrate concentrations and temperature were found to be effectively important. The highest productivity level was achieved at 42°C temperature and MgCl2 7.18 (g/L), yeast extract 1.1 (g/L), NH4NO3 3.65 (g/L) and NaHCO3 0.11 (g/L) concentrations. When the predicted optimum levels of effective factors were employed, the enzyme activity almost doubled (0.8 comparing to 0.39 U/ml) of the initial. Discussion and conclusion: The Idiomarina zobellii originated lipase is an  alkalophile enzyme. A significant increase in enzyme production, as large as  2.09 folds, is achievable   under optimized conditions that favours biotechnology and industrial applications.