Optimization and characterization growth conditions of lipase-producing bacteria from oil contaminated soil and sewage

الملخص EN

Ten samples of oil contaminated sewage and soil were collected from generators locations and car repair locations in Baghdad, Iraq for isolation of lipase- producing bacteria.

Enriched selective media technique was used for isolation of lipase- producing bacteria in which different inducers (olive oil and Tween 80) used for enzyme production.

The effect of different pH and temperatures were investigated.

Fifteen lipase - producing bacteria had been isolated; Pseudomonas aeruginosa (6 isolates), Escherichia coli (5 isolates), Klebsiella pneumonia (3 isolates) and Staphylococcus epidermidis (1 isolate).

Olive oil was found to be the more suitable source of carbon and lipid than Tween 80 for lipase- producing bacteria.

All lipase- producing bacteria were capable to grow at different pH except of E.coli and S.

epidermidis which could not grow at pH 9.

All lipase- producing bacteria were capable to grow at different temperature except of E.coli, K.pneumoniae and S.

epidermidis could not grow at 4ᴏC.

P.

aeruginosa was considered the best lipase- producing bacteria which could handle the different conditions, and the optimum conditions for growth and enzyme production was at 37 ᴏC, pH 7 and incubation period 48hrs.

or more.