Chlorpyrifos Tolerance, Utilization and Its Biodegradation by the cyanobacterium Nostoc muscorum

Asmaa A. Adway  et al.,        

chlorpyrifos | Nostoc muscorum       

Vol: 3; Iss: 3;  Mar-17 | ISSN: 2454-5422

Chlorpyrifos (CPS) is a highly toxic insecticide to aquatic organisms and one of the commonly used organophosphorus (OP) insecticides in EGYPT that are implicated in dangerous environmental and human health disturbs. In the present study, a blue green alga Nostoc muscorum was used to remove CPS, from contaminated wastewater. Treatment of algal strains with different concentrations of CPS increase chlorophyll (a), total carbohydrate and protein content at lower concentrations (0.2 and 20 ppm) while the higher concentrations (50, 100 and 200 ppm) reduced them. The algal culture was further subjected to grow under P-limitation in absence and presence of CPS. The growth and phosphorus content under P- limitation registered a very poor level. When the P- restricted medium was supplemented with CPS, the algal growth and phosphorus content of cells were increased significantly. Treatment of the tested strain with various concentrations of CPS gave a remarkable response in osmolytes and antioxidant enzymes where phenols, free proline content, catalase, peroxidase and superoxide dismutase activities were extremely significantly enhanced with increasing the concentration of CPS. Results of GC- MS showed that N. muscorum has the ability to degrade CPS to compounds with lower toxicity and beneficial uses and CPS and its main toxic metabolite 3, 5, 6-trichloro-2-pyridinol (TCP) were not detected. Morphological changes such as pigmentations increase in the number of heterocysts and reduction the size of vegetative cells were observed. The ability to survive at high concentration of CPS and enhanced degradation make this isolate an ideal and effective candidate for its application in such harmful chemicals bioremediation.