Isolation and identification of profenofos degrading bacteria

An enrichment culture technique was used to isolate bacterial strains responsible for the biodegradation of profenofos in a soil from Hubei province of central China. Two pure bacterial cultures, named W and Y, were isolated and subsequently characterized by sequencing of 16S rRNA genes and biochemical tests. Isolate W showed 96 percent similarity to the 16S rRNA gene of a Pseudomonas putida unlike Y which showed 99 percent similarity to the 16S rRNA gene of Burkholderia gladioli. Both strains grew well at pH 5.5-7.2 with a broad temperature profile ranging from 28º to 36 ºC. Bioremediation of profenofos-contaminated soil was examined using soil treated with 200 ug g-1; profenofos resulted in a higher degradation rate than control soils without inoculation. In a mineral salt medium (FTW) reduction in profenofos concentration was 90 percent within 96 hours of incubation. A literature survey revealed that no data is available regarding the role of Burkholderia gladioli on pesticide biodegradation as well as on profenofos.

Residue and Degradation of Profenofos in Soil / 环境与健康杂志

Objective To investigate the degradation rate of profenofos in soil. Methods The residues of profenofos at different times after spraying on soil were determined by GC-FPD method. Results Detection limit of profenofos in soil was 0.04 mg/kg. The recovery rates and relative standard deviation obtained by adding standard assay were 95.2%～98.7% and 3.4%～4.5% respectively. According to the dose recommended, degradation of profenofos sprayed on soil was consistent with one range dynamics. The half-life of profenofos in soil was 1.09 days. At the 13th day after spraying on soil, 98.3% of profenofos had degraded. Conclusion This method was simple, rapid, accurate and precise. The degradation of profenofos was more rapid and profenofos contamination in soil was not a serious problem.