Aims The chlorinated organic compounds are the most dangerous water pollutants in
industrial sites. The aim of this study was to investigate the biodechlorination of chlorinated
aliphatic compounds; trichloroethylene, dichloromethane, and 1,2- dichloroethane in aqueous
solution, using aerobic Sphingopyxix ummariensis bacteria.
Materials & Methods In this experimental study, aliphatic chlorinated compounds;
diclormethan, trichlorethylene, and 1,2-dichloroethane with purity of 99.9% were used. A
visible-ultraviolet spectroscopy was used to determine the cell growth from measuring the
turbidity of the medium at 600nm. The amount of released chloride was measured by an Ion
Selective Electrode (ISE). The live bacterial sample was inoculated into the Nutrient Broth
medium and was incubated at 30°C and 150rpm for 24 hours.
Findings The rate of dechlorination of diclormethan, trichlorethylene, and 1,2-dichloroethane
by Sphingopyxis ummariensis were measured as 1.3, 1.05, and 0.63mg/l.h, respectively. The
addition of glucose and yeast extract, as co-substrate, led to an increase in the cell growth
and dechlorination rate up to 3.28, 1.67 and 0.90mg/l.h, respectively. During experiment, the
highest dechlorination was measured at concentration of 2.5mM, at exponential growth phase.
Conclusion Sphingopyxix ummariensis bacteria is capable of biodechlorination of
chlorinated aliphatic compounds and can grows on trichloroethylene, dichloromethane, and
1,2-dichloroethane as a single carbon source and can decolorize them. This strain has the
highest growth and removal efficiency in eliminating dichloromethane as the sole source of
carbon along with glucose and yeast extract as co-substrate