Biotreatment of naphthalene by PAH-acclimated pure culture with white-rot fungus phanerochaete chrysosporium

Abstract

The tolerance of PAH toxicity for a PAH-acclimated pure culture with the fungus P. chrysosporium was evaluated by growth characteristics. The result showed that PAH-acclimated culture could still maintain its microbial activity, whereas the nonacclimated culture showed a declined growth when a high concentration of naphthalene (NTL) or benzo(a)pyrene (B(a)P) was present. In the treatment of NTL, the PAH-acclimated culture was also superior to the nonacclimated one. More than 90% of NTL removal had been attained by the PAH enrichment culture in agitated vessels within 24 h. However, in this experiment, about 20% of NTL was adsorbed on the fungal mycelia. After 4 days of reaction in the vessels, some ethyl acetate-extractable metabolites of NTL with high polarity in the HPLC elution were detected. One of these polar products was identified to be catechol compound. This study also demonstrated that NTL treatment in the aerated batch bioreactor was not comparable to that the agitated vessel owing to low efficiency in oxygen transfer of the system.