Selection of Culture Media and Optimization of Media Composition for Extracellular Production of Lipase byAcinetobactersp. AH-19

Abstract

A total of 20 strains of bacteria were isolated from cow shade area soil collected in India. The isolated strains were screened using Rhodamine B dye on tributyrin containing nutrient agar petriplates. One isolated strain, exhibiting a broader clear zone than the remaining ones, indicating its higher lipase activity, was selected and identified as Acinetobacter sp. AH-19 based on morphological and biochemical characterization. Out of the four culture media (M-I to M-IV) tested, the maximum production (78 U/ml) of lipase was observed in M-IV, that consisted of (% w/v): starch (0.8); peptone (1.0); NH4Cl (0.5); MgSO4 (0.05); CaCl2 (0.06); K2HPO4 (0.09); olive oil (0.2% v/v) and tween-80 (0.2% v/v). Optimization of media composition of M-IV for the production of lipase was performed by one factor at a time approach and the maximum production of lipase was observed at (% w/v): starch (0.4) 87 U/ml, peptone (0.8) 110 U/ml, NH4Cl (1.0) 114.5 U/ml, MgSO4 (0.02) 121 U/ml, CaCl2 (0.1) 129 U/ml, K2HPO4 (0.05) 135 U/ml, Olive oil (0.25% v/v) 149 U/ml and tween-80 (0.25% v/v) 158 U/ml.