Stereo Binocular Microscope

In Pakistan, insecticides are widely used in agriculture. Despite their biodegradable nature, some are highly toxic and their residues are found in the environment. Moreover, its removal from wastewater generated during manufacture becomes inevitable. Reports on the mineralization of a spectrum of different insecticides by a single potential strain are scarce. In this study, a bacterial strain was isolated from soil using enrichment technique and identified as Pseudomonas sp. by microscopic examination and biochemical tests. Growth curve experiments showed that Pseudomonas strain was able to grow in nutrient medium containing malathion (35-220 mg L^-1), methamidophos (80-320 mg L^-1), cartap (60-120 mg L^-1) and cypermethrin (40-125 mg L^-1) pesticide. However, the optimum concentration which support normal bacterial growth during 24 h was found to be 120 mg L^-1 malathion, 160 mg L^-1 methamidophos, 80 mg L^-1 cartap and 60 mg L^-1cypermethrin. When compared with the control test, a significant increased in bacterial population was noted at low concentration of each pesticide, however at high concentration lag phase increased but no zone of inhibition observed. These data indicate that the isolated Pseudomonas strain can be used as a microorganism for the bioremediation of pesticide contaminated soil or water.


Click Here to read the entire article...