BIODEGRADATION OF HEXAMINE IN INDUSTRIAL WASTEWATER OF ANKLESHWAR UNIT IN GUJARAT STATE OF INDIA USING AN INDIGENOUS BACTERIAL ISOLATE

The industrial waste water generated during Hexamethylenetetramine (Hexamine) production mainly contains hexamine together with methanol and formaldehyde. Hexamine being bactericidal in nature and also resistant to biodegradation, it is pertinent to treat effluent having such compounds before discharging in natural streams. A bacterial strain capable of degrading effluents containing hexamine compounds from hexamine production unit of Ankleshwar was isolated. The isolate was put through phenetic and genetic identification on the basis of morphology, biochemistry, physiology and 16S rRNA analysis. It was a Gram negative rod capable of utilizing hexamine effluent as sole source of carbon and nitrogen. BLAST search of the 16S rRNA sequence of isolate (MTCC accession no 5833) exhibited maximum similarity (99.15%) with Pseudomonas taiwanensis having capability to degrade efficiently 50 % or more of 5000 ppm of hexamine in 22 days under aerobic conditions at alkaline pH. The isolate could reduce COD of the effluent by 70% and ammoniacal nitrogen by 50.0% when tested at 5L, 200 L and plant level bioreactors.