Bacterial Degradation of PCB 70 and its Hydroxy Derivatives is an Environmentally Friendly Way to Destroy Pops

Abstract

One of the problems of our time is the environmentally safe destruction of polychlorinated biphenyls (PCBs) and their hydroxylated derivatives. The aim of the study was to investigate the features and prospects of the decomposition of PCB 70 (2,5,3’,4’-tetrachlorobiphenyl) and hydroxylated chlorobiphenyls derived from it by Rhodococcus wratislaviensis strain CH628. As a result of the application of methods of periodic cultivation, gas chromatography and light spectrometry, it was found that the efficiency of destruction of PCB 70 1 g of cells of strain CH628 was 90 mg PCB/day, and the same indicator for a mixture consisting of hydroxy derivatives obtained from PCB 70 was 56 mg PCB/day. It was shown that the strain uses all components of the mixture of hydroxy-PCB 70 as a growth substrate, but with different degradation rates. When cultivated in a mineral medium with PCB 70 or a mixture of hydroxy-PCB 70, strain CH628 forms biofilms. The analysis of the obtained results shows that the use of the Rhodococcus wratislaviensis CH628 strain will make it possible to develop a technology for the environmentally safe destruction of PCB 70 and hydroxy-PCBs derived from it.