RAJESH SAWHNEY, ARUN KUMAR, ROBINA AND JAYATA
Abstract
Congo red, a carcinogenic diazo dye is discharged through industrial effluents in the environment. The removal of this hazardous dye from effluents is important for health and environment protection. In recent past, immobilization has come up as a promising biological tool. The present study highlights the immobilization of Bacillus subtilis sub sp. subtilis RA-29" on a suitable matrix and the potential of immobilized whole cells to decolourize congo red. The whole cell immobilized calcium alginate beads were stable for 7 days. The immobilized RA-29 exhibited cell density dependent decolourization. Maximum congo red decolourization (81.55%) was achieved at cell density of 30ug/mm3 after 48 hr of incubation at 370C under static condition. The calcium alginate immobilized “RA-29” showed operational stability with efficient decolourization up to five cycles with minimum decolourization percentage falling to 61.11%. The immobilized Bacillus subtilis could be commercially viable biotechnological tool for bioremediation of dye contaminated industrial effluents.