Vijayalakshmi P. and Usha M. S.
Pseudomonas putida isolated from an agricultural soil was used for degradation of chlorpyrifos in free and immobilized condition. Free cells of Pseudomonas putida were able to show 76% degradation of pesticide at 2% concentration at pH 7, temperature 35°C, 10 ml of inoculum size, shaking speed of 150 rpm and in presence of 200 mg/l glucose and 300 mg/l yeast extract. With further increase in pesticide concentration efficiency of free cells reduced. Efficiencies of the immobilized cells were better compared to free cells. When Ca-alginate immobilized cells were used for degradation studies, 96% degradation was recorded at 2% pesticide concentration. At 10% concentration of pesticide, free cells could show only 43% degradation, whereas immobilized cells could show 63% degradation of the pesticide.
