STUDY OF PHENOL DEGRADING BACTERIUM ISOLATED FROM A PETROCHEMICAL CONTAMINATED SITE

Phenolic compounds have increasingly found their way into the environment following the industrial revolution. The decontamination of industrial effluents is a prerequisite to effluent treatment and discharge to prevent the detrimental effects of toxic compounds on the environment. In the present study, an attempt has been made to isolate a phenol degrading bacterium and characterize the physicochemical parameters to optimize its degradation potential. To increase the probability of isolating a phenol degrader, the samples were collected from petrochemical sites and the efficiency of bacterium was estimated by 4-amino-antipyrene method. Among the twenty six isolates obtained in our study, Rhodococcus biphenylivorans (R. biphenylivorans) strain RARA1707 (NCBI accession no. MK841038) tolerated up to 1100 ppm phenol. Moreover, this isolate could utilize phenol as a sole source of carbon. The optimum conditions for phenol degradation were optimized by ‘one factor at a time’ approach. R. biphenylivorans showed maximum degradation in MSM-D medium (pH: 8) containing 0.45% tryptone, 30°C under shaker condition (130 rpm). The optimum inoculum size was found to be 2% at 0.7 O.D_540nm. Our study suggests that R. biphenylivorans RARA1707 strain is naturally adapted to metabolize phenolic compounds and hence may prove to be a potential candidate for its bioremediation.