Biodegradation of omethoate by Bacillus sp. YB-10: optimization of culture conditions and degradation characteristics

Abstract

Omethoate is an acute organophosphorus pesticide which is widely used. It presents a high pollution potential and health risk nowadays. In this study, Bacillus sp. YB-10, which was isolated from the activated sludge of a pharmaceutical wastewater treatment plant, was used for degrading omethoate. The culture conditions and degradation characteristics were investigated. Results showed that the Bacillus sp. YB-10 could degrade omethoate through co-metabolism. The optimal carbon and nitrogen sources were glucose and NH4NO3, respectively. Response surface methodology (RSM) results showed that the most appropriate nutrition ratio of C:N:P was 3:1:1 when degrading 1,000 mg/L of omethoate. Omethoate degradation kinetics could be described by a first-order rate equation. The optimal degradation conditions were pH of 7.0, temperature of 30℃, initial bacteria concentration of 0.25%, rotation speed of 150 r/min. Under the optimal conditions, the degradation rate reached 77.24% within 5 d by the Bacillus sp. YB-10 when the initial omethoate concentration was 1,000 mg/L.

Bioremediation of Neonicotinoid Pesticide, Imidacloprid, Mediated by Bacillus cereus

“…MJ15 by inhibiting nucleic acid and protein production. Li et al [42] conducted a study to examine the impact of pH levels ranging from 5.0 to 8.0 on the degradation of omethoate, which is an acute organophosphorus pesticide. The most effective degradation was observed at pH 7.0, where the degradation rate increased rapidly over time, reaching 77.11% within 5 days.…”