Biodegradation of chlorpyrifos by bacterial consortium isolated from agriculture soil

Abstract

Organophosphorous pesticides are widely used in agriculture to control major insect pests. Chlorpyrifos is one of the major organophosphorous pesticides which is used to control insects including termites, beetles. The widespread use of these pesticides is hazardous to the environment and also toxic to mammals, thus it is essential to remove the same from the environment. From the chlorpyrifos contaminated soil nine morphologically different bacterial strains, one actinomycete and two fungal strains were isolated. Among those isolates four bacterial strains which were more efficient were developed as consortium. The four bacterial isolates namely Pseudomonas putida (NII 1117), Klebsiella sp., (NII 1118), Pseudomonas stutzeri (NII 1119), Pseudomonas aeruginosa (NII 1120) present in the consortia were identified on the basis of 16S rDNA analysis. The intracellular fractions of the consortium exhibited more organophosphorus hydrolase activity (0.171 ± 0.003 U/mL/min). The degradation studies were carried out at neutral pH and temperature 37°C with chlorpyrifos concentration 500 mg L(-1). LC-mass spectral analysis showed the presence of metabolites chlopyrifos-oxon and Diethylphosphorothioate. These results highlight an important potential use of this consortium for the cleanup of chlorpyrifos contaminated pesticide waste in the environment.

Chlorpyrifos: pollution and remediation

“…(Lakshmi et al 2009). A consortium consisting of Klebsiella sp., Pseudomonas aeruginosa, Pseudomonas stutzeri, and Pseudomonas putida isolated from chlorpyrifos contaminated agricultural soil, which could degrade chlorpyrifos even at 500 mg L -1 , highlights the potential use of consortia to clean up contaminated sites (Sasikala et al 2012). Degradation efficiency and optimal conditions for efficient chlorpyrifos degradation by co-culture of chlorpyrifos degrading bacterium Serratia sp.…”

Structural and metabolic responses of microbial community to sewage-borne chlorpyrifos in constructed wetlands

“…There were 5 dominant bands (a, n, o, u, x) sequenced. Three out of the five bands were similar to chlorpyrifos-degrading bacteria in CWs (Pinjari et al, 2012;Sasikala et al, 2012;Feng et al, 2014). Hence, there might be considerable potential degrading ability of chlorpyrifos in each treatment.…”

“…The efficiency of different microbial degradation pathways has also been studied. Numerous studies have concentrated on the selection of specific pesticide-degrading bacteria in different pesticide-polluted samples (Lakshmi et al, 2009;Sasikala et al, 2012). Nevertheless, research on the effect of pesticides on microbial community dynamics should not be neglected.…”

Microbial degradation of pesticide: A review

“…When growing in minimal salt medium containing 2 mg.ml Chlorpyrifos as the solitary carbon source it was demonstrated that as high as 90% chlorpyrifos was utilized by MAS-1 just in 24 h (Munazza et al, 2012). In a parallel study, Sasikala et al (2012) isolated nine different bacteria from chlorpyrifos contaminated soil of which four were further used in preparation of consortium for the degradation of pesticide. In another study, it has been reported that 4 strains of Pseudomonas isolated from a water waste irrigated agri-soil in India, were able to utilize chlorpyrifos as an exclusive carbon source (Bhagobaty and Malik 2008).…”