Dechlorination of 2,3,5,6-tetrachlorobiphenyl by a phototrophic enrichment culture.

A phototrophic enrichment culture, using acetate as carbon source, reductively dechlorinated 2,3,5,6-tetrachlorobiphenyl. ortho chlorines were removed preferentially over meta chlorines. Tri- and dichlorobiphenyls were the major products. During 14 months incubation, chlorine was removed from 58% of the target molecules; 19% of the total chlorines were removed. Dechlorination did not occur in a control culture incubated in the dark.