Isolation and identification of lipase producing bacteria and the optimization of fermentation conditions

A wild lipase-producing strain was isolated from long waste-oil-polluted soil with enzyme activity of higher than 5 U/mL and identified as Pseudomonas aeruginosa by the identification of 16S rRNA,and was named B6.The fermentation condition of lipase production strain were optimized and the effect of carbon sources,nitrogen sources,and inoculum size on the lipase production were studied.The result showed that the optimal medium composition for lipase production was as follows(%,w/v): glucose 0.4,yeast extract 0.7,(NH4)SO4·0.7,MgSO47H2O 0.1,K2HPO4 0.1.The optimal initial pQH and temperature of fermentation medium was 6.5 and 30℃.This experiment lay the foundation for the further study of lipase production fermentation.