Objective: Polychlorinated biphenyls (PCB) are persistent organic pollutants that are widely distributed in the environment. PCBs are aromatic compounds have more than 210 congeners, nonvolatile, chemically inert and do not undergo oxidation, reduction or addition reactions, elimination or electrophilic substitution reactions except under extreme conditions. Their improper disposal in storage and disposal area has negative impact on the ecosystem. Although Chemical methods are available for the degradation, they tend to emit more toxic chemicals. Alternative the biological methods are safer and cost effective. In this context, 2, 4 Dichlorobiphenyl, (a PCB congener) degrading bacterial isolates which have been evaluated for substrate affinity using PCB congener mix.
Methods: In the present study, 2, 3, 5, 6 tetrachlorobiphenyls and 3, 5’, 3, 5 tetrachlorobiphenyl in PCB congener mix degradation by previously characterised Pseudomonas isolates GSa and GSb was studied using GC-MS.
Findings: Two constantly overlapping bacterial isolates identified as Pseudomonas sp., capable of degrading 2, 4 Chlorobiphenyl degrading, showed its diversity of degrading other PCB congener mix. On GC-MS analysis of the cell free extract showed 60 and 70% degradation as per the ECD values.
Applications: Therefore, the present paper is first of its kind, as 2, 4 CB degrading Pseudomonads in tern degrade other PCB congeners perhaps showing wide application on in situ bioremediation since the contaminated site contains variety of congeners.