Biodegradation of Polychlorinated Biphenyls by and Isolated from Contaminated Soil


1 Department of Chemical and Petroleum Engineering, Sharif University of Technology, Tehran, Iran

2 Biochemical and Bioenvironmental Research Center, Sharif University of Technology, Tehran, Iran


Polychlorinated biphenyls (PCBs) cause many significant ecological problems because of their low degradability, high harmfulness, and solid bioaccumulation.Two bacterial strains were isolated from soil that had been polluted with electrical transformer liquid for more than 40 years. The isolates were distinguished as Lysinibacillus macrolides DSM54Tand Bacillus firmus NBRC15306Tthrough 16S rRNA sequencing analysis.This is the primary report of an agent of the genus Bacillus firmus equipped for the removal of PCBs. The strains could develop broadly on 2-Chlorobiphenyl and 2,4-dichlorobiphenyl. GC/MS analysis of individual congeners revealed up to 80% degradation of the xenobiotics in 96h, attendant with cell proliferation of up to two orders of extent. More extensive investigation of the isolates may be helpful in surveying detoxification forms and in planning bioremediation and bioaugmentation strategies.