Abstract:

A bacterial strain named N-02 capable of degrading cypermethrin was isolated from long-term cypermethrin
contaminated orchard soil by using enrichment culture. Based on the morphology, physio-biochemical characteristics, and
16S rDNA sequence analysis, strain N-02 was identified as Aeromonas punctata. The degradation rate of cypermethrin was
62.31% when the strain were cultured at 35 ℃ for 96 h in LB medium containing 20 mg/L cypermethrin at pH 7.5. A wide
degradation spectrum of pyrethroid by strain N-02 was observed, and the degradation rates of β-cypermethrin, deltamethrin
and fluoride cypermethrin after 96 h were 40.17%, 33.26% and 30.45%, respectively.

Key words: cypermethrin, Aeromonas punctata, degradation characteristics, degradation spectrum