| One fenpropathrin-degrading bacterium strain was isolated from the soil identified as Ochrobactrum anthropi.The gas chromatography (GC) method was used to measure fenpropathrin residue, the fenpropathrin concentrations were set at 1mg/L, 10mg/L and 100mg/L, respectively solved in the water, the recovery rates were between 78. 14%and 102. 28%, and the coefficients were ranged from 2. 68% to 4. 33 %,the standard curve formulum was Y=1E+06X+594018, R2=0.998.The bacterium was cultivated 72h in basic culture medium with 200mg/L fenpropathrin and shaking at 180r/min at 30℃, fenpropathrin was degraded by 76% within 7 days, but no degradation of fenpropathrin occurred in the liquid bovine (LB) medium.The bacterium grew well in basic culture agar medium containing fenpropathrin(100mg/kg-500mg/kg), and could accumulate the dissolved pesticide. Cultivated in basic culture agar medium containing fenpropathrin 300mg/kg, 400mg/kg, 500mg/kg, fenpropathrin was detected much higher than that in the medium and the dosage in the bacterium was positively correlated with that added in the medium.With liquid nitrogen and Na2HPO4-NaH2PO4 buffer (pH7.0), esterase existed both inside and outside the cell system. And the activity was higher outside cell system than that inside. Set fenpropathrin at lOOmg/L and temperature at 37℃, the degradation activity was 26. 23μg/mg/30min. Meanwhile, fenpropathrin could inhibit esterase and the inhibition rate increased with fenpropathrin concentration. At 37℃, 25mg/L fenpropathrin could inhibit esterase by 26.6% within 30 mins and 100mg/L could inhibit by 85.6%.Use diatomite as the strain carrier and keep at 4℃for 60 days, the bacterium individuals did not decrease significantly. The bacterium— diatomite mixture could decrease fenpropathrin in the simulated soil by 78. 13% within 3 days at room temperature. Fenpropathrin residue in the tea leaves was degraded by 26. 2% within 7days by the bacterium—diatomite mixture combined with Tween-20.
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