Biodegradation of fenpropathrin by a novel Rhodopseudomonas sp. strain PSB07-8

The aim of our study was to isolate a fenpropathrin-degrading bacterial strain and to determine its effectiveness in bioremediating fenpropathrin-contaminated soil in the laboratory. We isolated a bacterial strain from soils and named it as PSB07-8, and showed that this organism was able to degrade pyrethroid pesticide fenpropathrin. The organism was identified as a strain of Rhodopseudomonassp.The strain PSB07-8 degraded fenpropathrin in a co-metabolic way, and the optimal condition of degradation was at temperature of 30°C and pH value of 7. Moreover, the strain PSB07-8 could effectively degrade cypermethrin and bipthenthrin, but only slightly for deltemethrin, cyfluthrin and esfenralerate. We found that the degradation rate was negatively correlated with the fenpropathrin concentration in a certain range. In addition, our soil degradation test showed that in sterilised soils with 20 mg/l or 40 mg/l fenpropathrin, the strain PSB07-8 could complete 100% or achieve 44.7% of fenpropathrin degradation in 15 days. To our best knowledge, this is the first report of a strain of genus Rhodopseudomonas with an ability of degrading fenpropathrin in soil.