Tolerance of Two Ciliates, Stylonychia mytilus and Paramecium caudatum, Isolated from Industrial Effluents to an Organophosphate, Endosulfan and their Potential use in Bioremediation of Insecticide- contaminated Wastewater

Two ciliate protozoans, Stylonychia mytilus and Paramecium caudatum isolated from tannery effluent and cultured in a medium containing inorganic salts showed tolerance against endosulfan (1.8 µg/ml). The protozoans uptake the insecticide from the medium for utilization. Stylonychia mytilus reduced 21% endosulfan from the medium within 48 hours of inoculation of insecticide containing medium with the protozoan cells; at the end of 8 days of culturing, the reduction of endosulfan in insecticide containing medium was 78%. The Paramecium caudatum on the other hand reduced concentration of endosulfan in medium by 11% after 2 days of inoculation, whereas after 8 days of culturing, the reduction was 72%. The insecticide utilization by protozoa as a carbon source for their growth can be exploited for insecticide removal and environmental clean-up operations.