Isolation of Cypermethrin-degrading Bacteria and its Degrading Characteristics

The isolation of cypermethrin-degrading microorganisms was carried out and twenty-two strains were isolated from contaminated soil and sludge, of which two strains could use cypermethrin as sole carbon source and showed a high degradation rate. The effects of culture conditions on the degrading characteristics were further investigated. The results showed that the degradation rate of two strains was in proportion to the concentration of cypermethrin as the concentration was below 200 mg·L-1. The adding of carbon source or nitrogen such as starch, glucose, yeast extract and peptone could enhance greatly degradation rate.