Degradation and mineralization of DDT by the ectomycorrhizal fungi, Xerocomus chrysenteron

• The mineralization ability of ECMF on DDT was investigated for the first time.
• We are the first to prove DDT could be mineralized by Xerocomus chrysenteron.
• X. chrysenteron showed much more powerful DDT tolerance than other fungi in similar studies.

One strain of ectomycorrhizal fungi, Xerocomus chrysenteron, had been investigated for its ability to degrade 1,1,1-trichloro-2,2-bis(4-chlorophe-nyl) ethane (DDT) by measuring unlabeled DDT and identifying its metabolites, and determining the mineralization of [13C]DDT in pure cultures. After 45 d incubation, about 55% of the added DDT disappeared from the culture system, less than 5% remained in the nutrient solution, and about 44% was retained in the mycelium. Inoculation with mycelium enhanced the degradation of DDT in soil, and alleviated enrichment of DDT in plants. The metabolites identified by gas chromatography–mass spectrometry were 1,1-dichloro-2,2-bis(4-chlorophenyl) ethane (DDD), 1,1-dichloro-2,2-bis(4-chlorophenyl)ethylene (DDE), and 4,4′-dichlorobenzophenone (DBP). There were significant differences in the δ13C of released CO2 between [13C]DDT and DDT cultures, which indicated X. chrysenteron was able to mineralize DDT to CO2.