Isolation and Identification of Bacteria from Transformer Oil Contaminated Soil

Abstract

Background: Poly chlorinated biphenyls (PCBs) are organic chemicals with toxigenic, carcinogenic affecting human health and the environment using as dielectric fluids in transformers as a cooling and insulating medium containing. Materials and Methods: Soil samples were collected from transformer oil contaminated soil at different workshops in three different districts of Khyber Pakhtunkhwa i.e. Peshawar, Nowshera and Kohat and were kept at 4°C before analysis. The samples were subjected to Pure culture isolation through a selective medium (Medium A). After incubation for 24 to 48 hours at 37°C with 1% transformer oil as sole source of carbon, the isolates were examined for their colony size, shape, margin, consistency, opacity, elevation and pigmentation; while Gram reaction and cell morphology were examined microscopically. Furthermore the biochemical tests were also done for identification of the bacteria. Results: A total of 14 isolates were obtained from all the transformer oil contaminated soil samples after examining the samples indicates the bacteria namely Bacillus, Micrococcus, Pseudomonas, Acinetobacter and Staphylococcus were identified during the current study. Conclusion: Based on the results of the study, five bacterial species capable of degrading PCBs in transformer oil, from which it was concluded that PCB compounds can be degraded by some microorganisms under aerobic conditions.