Metabolism of 4-chlorobiphenyl by lichens

Eighteen lichens from a variety of habitats were treated with 4-chlorobiphenyl (4-CB). All, as determined by means of radioactive tracers, were shown to partially convert 4-CB to 4-chloro-4′-hydroxybiphenyl. Only one species (Pseudocyphellaria crocata) produced a further major metabolite not previously reported, namely 4-chloro-4′-methoxybiphenyl. The formation of the hydroxy derivative by Cladonia rangiferina and Lasallia papulosa was proven by isolation and chemical identification. Difficulties in the recovery of both the starting material and the metabolites from Pseudocyphellaria were encountered.