Determination of chrysene degradation under saline conditions by Fusarium sp. F092, a fungus screened from nature

Sixty-two rotted wood and soil samples were used to screen for chrysene-degrading fungi. A strain of Fusarium, named F092, was identified as most capable of degrading chrysene. F092 was active under saline and nonsaline conditions, breaking down 48 % of the chrysene in 30 d. The percentage of chrysene degraded did not change at 35 ‰ salinity with pH 8.2 in solid and liquid cultures. The degradation under saline conditions increased about 0.6- and 2.1-fold in cultures with polypeptone and Tween80, and 0.03-fold in agitated cultures. F092 secreted nonligninolytic enzymes named 1,2-dioxygenase and 2,3-dioxygenase. The level of 1,2-dioxygenase activity reached 203.5 U L−1 at 30 d and that of 2,3-dioxygenase activity, 29.7 U L−1 at 40 d. The degradation pathway was clarified from the intermediates produced; chrysene 1,2-oxide, chrysene trans-1,2-dihydrodiol, 1-hydroxy 2-naphtoic acid, and catechol. F092 is a potential degrader of chrysene for bioremediation.

► A strain of Fusarium sp. F092 was the most capable chrysene degrader.
► It degraded 48 % of chrysene.
► The rate of degradation increased by addition Tween80, polypeptone, and agitation.
► The intermediates products during chrysene degradation were identified.
► This strain is likely to have further applications in bioremediation.