ISOLATION OF THE LIPASE PRODUCING BACTERIA FROM OILY WASTEWATER AND DETERMINATION OF THE VARIABLES FOR OPTIMUM LIPASE PRODUCTION

摘要

Isolated bacteria from oily wastewaters were screened for lipase activity. The highest lipase activity was found in an isolated strain Flavobacterium sp. Some parameters influencing the extracellular lipase production of Flavobacterium sp. were investigated using the Plackett-Burman design and Response Surface Methodology technique. In the first step, the Plackett-Burman design was used to evaluate the medium components (Tween80, glucose, NaCl, peptone, yeast extract, pH, KH_2PO_4 and olive oil) for lipase production by Flavobacterium sp. under batch conditions. Peptone, yeast extract and KH_2PO_4 had most significant effects on the lipase production. In the second step, optimization of these three medium components was studied in twenty experimental trials. The optimum values of peptone, yeast extract and KH_2PO_4 were 15, 10 and 2.5 g L~(-1), respectively. Maximum lipase activity (4.25 U/ml) was obtained using the optimized culture.