Profenofos insecticide degradation by novel microbial consortium and isolates enriched from contaminated chili farm soil.

ABSTRACT

Profenofos (PF) is one of the heavily used organophosphorus pesticides (OPPs) of which its contamination is ubiquitous in an agricultural area. This study aims to acquire and characterize PF-degrading bacterial cultures from contaminated soil. OPP degradation by the novel isolates was then investigated. The experiment was performed at the initial PF concentration of 20 mg/L. The result showed that the enriched consortium comprised three predominant PF-degrading strains designated as PF1, PF2, and PF3. The isolates (PF1, PF2, and PF3) were characterized as Pseudomonas plecoglossicida, Pseudomonas aeruginosa, and P. aeruginosa, respectively. A consortium and all isolates could utilize PF as a sole carbon source with PF removal of more than 90% via a hydrolysis process. The bacterial growth and PF degradation rates followed the first-order kinetic reaction with the rates of 0.4 to 2.7/h and 0.15 to 1.96/h, respectively. Additional carbon supplement deteriorated PF biodegradation. The enriched cultures were also capable for degrading chlorpyrifos and dicrotophos pesticides (33-73% removal). The results indicated that the consortium and isolates are efficient for PF and other OPP degradation and have potential for PF remediation.