Microbial cultures enriched from a diesel fuel contaminated aquifer we
re able to grow on p-xylene under denitrifying conditions. The oxidati
on of p-xylene to CO2 was coupled to the reduction of NO3-. The enrich
ment cultures also grew on toluene and m-xylene, but they did not degr
ade benzene, ethylbenzene, and o-xylene.