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In order to evaluate the potential ecological risk and the toxic effect of landfill leachate (LL), Phanerochaete chrysosporium was exposed to LL and their biochemical response was observed by using antioxidant parameters. Phanerochaete chrysosporium, ME 446, was kept at 4 °C after being sub-cultured at 28 °C on Sabouraud Dextrose Agar (SDA). Superoxide dismutase (SOD), catalase (CAT) activities, and malaondialdehyde (MDA) and glutathione (GSH) levels of P. chrysosporium exposed to different dilution rates of leachate (1/10 and 1/20) for 24 and 96 h were analyzed by using the ELISA method. The physiochemical parameters such as pH, conductivity, total dissolved solids (TDS), dissolved oxygen (DO), chemical oxygen demand (COD) of leachate, and reference water were analyzed by using the YSI Professional Plus handheld multiparameter meter. In this study, SOD activities were decreased in the application groups compared with the Control Group at the 24th and 96th hours. CAT activities and GSH levels increased in the application groups compared with the Control Group at the 24th hour but decreased at the 96th hours. MDA levels increased in all of the application groups when compared with the Control Group for both 24 and 96 h. Different concentration of LL induces oxidative stress in P. chrysosporium, increased CAT activity and MDA levels, and decreased SOD activity and GSH levels.

When exposed to higher Pb(2+) concentration, Phanerochaete chrysosporium secreted higher content of oxalate and thiol compounds. An earlier and faster increase in oxalate was observed after short-term exposure, comparing with a gentle increase in the thiol compounds. In the extracellular polymeric substances (EPS) extract, more oxalate and T-SH were detected when the initial Pb(2+) was higher, and the variations were different from the situation in the culture medium. In EPS solution, the oxalate amount was more closely related with Pb than that of thiol compounds. pH condition in the whole Pb removal process by P. chrysosporium ranged from 4 to 6.5 and was more beneficial for the binding of Pb(2+) to carboxylic groups in the oxalic acid. More Pb(2+) induced more EPS amount, and the increase of EPS amount influenced the immobilized oxalate more seriously. The present study can supply more comprehensive information about the metal passivation mechanism in white-rot fungi and provide meaningful references for an enhanced removal of heavy metals.

Introduction: The toxic effect of the oxidation hair dyes on Phanerochaete chrysosporium was investigated by exposure of this fungus in a nitrogen-limited culture medium to various concentrations of the oxidation hair dyes., Results: The results showed that both the size and the dry weight of the mycelial pellets of P. chrysosporium could be reduced when the concentration of the oxidation hair dyes was higher than 300 mg/L. By using the AFLP analysis and the UPGMA dendrogram, the DNA damage of P. chrysosporium by the oxidation hair dyes was also detected. Comparing with that in the control, the percent polymorphism under different concentrations of the oxidation hair dyes increased. In the meantime, the DNA similarity was decreased, which meant that the DNA damage was aggravated with an increase in the concentrations of the oxidation hair dyes., Conclusion: Thus, as an environmental pollutant, the oxidation hair dyes have a toxic effect on P. chrysosporium at both cellular and molecular levels.