Production of an alkaline lipase by Acinetobacter radioresistens

Alkaline Lipase production by Acinetobacter radioresistens was investigated and the role of culture conditions was examined. The enzyme had an optimum pH of 10 and was stable over a pH range of 6-10; it could have great potential for application in the detergent industry. The optimal temperature and pH for lipase fermentation were 30 degrees C and 7, which were related to cell growth, protease formation, and stability and reactivity of lipase. A high lipase yield could be obtained during prolonged cultivation in the presence of n-hexadecane. With additional olive oil supplementation, the volumetric productivity of lipase could be improved; however, the lipase yield decreased with increasing concentrations of olive oil. The increase in the rate of lipase formation by olive oil in the presence of n-hexadecane was attributed to its enhancement of the uptake of n-hexadecane; the hydrolytic products of olive oil promoted the emulsification of n-hexadecane. Because olive oil repressed the synthesis of lipase, optimization in formulating the medium composition is considered necessary.