Abstrakt

Degradation of chloropyrifos using free and sol-gel immobilized bacteria

Rafik Helles, Abdelraouf Ali Elmanama, Mona Ishak Fahed, Hoda Hassan Abo-Ghalia, Mai Ramadan, Azmi Abu Daka

Chorpyrifos-degrading bacteria were isolated fromKhan-Younes soil and identified as Burkholderia cepacia. The ability of the strain to degrade chorpyrifoswere examine using both free and sol-gel immobilized bacteria using 200mg/L chorpyrifos. The concentration of the pesticides was lowered to less than 4mg/Land 58mg/Lfor free and immobilized respectively. Higher degradation rate of chorpyrifos was observed for free bacteria compared with immobilized bacteria. Optimum pH was found to be 7 for the degradation process for both immobilized and free bacteria. Temperature has an effect on the degradation of chorpyrifos by the two forms of bacteria, maximumdegradationwas observed at 30oC.