Optimization of medium constituents for pyrethroid pesticide degradative enzyme expression by recombinant Escherichia coli in shake flask fermentation

The medium for pyrethroid pesticide degradative enzyme expression by recombinant Escherichia coli was optimized by investigating the effcets of carbon sources, organic nitrogen sources and inorganic nitrogen sources on cell growth and expression of degradative enzyme through single facor and orthogonal experiments. The results showed that the optimal medium composition was glycerol 20 g/L, yeast extract 20 g/L, (NH4)2SO4 5 g/L, NaCl 5 g/L, Na2HPO412H2O 10.7 g/L, KH2PO4 2.7 g/L, kanamycin sulfate 50 g/L, pH 7.0. By using the optimum medium, the activity of degradative enzyme increasedby about 86% compared with the original medium.