Study the Growth Kinetics of Pseudomonas aeruginosa Degrading Some Pesticides which Isolated from Cultivated Soll

The ability of the bacterium Pseudomonas aeruginosa that isolated from cultivated soil to degrade some pesticides like malathion, cypermethrin and carbofuran was studied by investigate the growth kinetics of bacteria in pesticides enriched media at different concentrations. It was found that P. aeruginosa was more resistant to malathion than other pesticides. Growth curves of bacteria showed it ablility to grow in mineral salts medium contain malathion 0.1-1%, cypermethrin 0.1- 0.5% and carbofuran pesticide 0. 1- 0.7%. The optimum concentration which support normal bacterial growth during 24 h was found to be 0.7% malathion, 0.3% cypermethrin and 0.5% carbofuran. When compared with the control test, a significant increased in bacterial population was noted at low concentration of each pesticide. The lowest generation time of P. aeruginosa was 75 min. when they grown in mineral salts medium which containing malathion at concentration 0.5%. The results showed that the local isolate P. aeruginosa had the ability to degrade the malathion even at high concentration, and we concluded that bacterium can be used as a microorganism for the bioremediation of pesticides contaminated soil and water.