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The fungal degradation of toxic alkaloids, papaverine and harmaline, which present in some wild grass, were firstly investigated by using the lignin-degrading basidiomycete Phanerochaete chrysosporium. The fungi could quickly degrade the papaverine and harmaline, especially in the case of P. chrysosporium in Mn-including medium. The nutrient nitrogen concentration had a great effect on the degradation rate of substrates. The papaverine was degraded more effectively under low concentration of nitrogen (LN) condition. But the harmaline could be greatly degraded under both low and high nitrogen concentration. These results strongly suggest that the lignin-degrading basidiomycete Phanerochaete chrysosporium have great potential in degradation of toxic alkaloids of wild grass.

Problems such as agricultural safety and environmental pollution by using chlorpyrifos and other pesticides had become major issues which needed to be solved. The white rot fungi had a unique degradation ability and mechanism to a variety of xenobiotic, which had a good prospect in the bioremediation of the environment. Optimizing the conditions of degrading pesticides chlorpyrifos by using phanerochaete chrysosporium were studied in this work. The optimal culture medium and initial pH value were HCHN and 5.5 respectively. The initial concentration of chlorpyrifos added into the culture could be reach 200mg/L with a highest degradation rate at the range of experimental concentration. In addition, veratryl alcohol and Mn2+ can effectively promote the degradation. The degradation rate of chlorpyrifos could arrive to 90% in the 15 day under optimal conditions. The present works lay the foundation of study on reducing the residual chlorpyrifos in agricultural and forest products and soil bioremediation in the next step.

Laccase from Coriolus versicolor was used to study the conversion of 2,4-Dichlorophenol (DCP). DCP can be transformed nearly half after treating by 0.1ΔA/mL for 2h, and the conversion ratio DCP reached above 80% after treating for 5h when the initial DCP was 80mg/L, pH 6.5, temperature 35°C High DCP concentration will inhibit the conversion. The existents of ethanol, dioxane and acetone decreased the DCP conversion. But conversion ratio was still above 50% after 4h and above 65% after 7h, which implied that when the substrates were poorly soluble in water, the organic solvents can be chosen to increase their solubility and make their enzymatic conversion possible. UV, FTIR and HPLC spectra were used to analyze the conversion production, and results showed that DCP was degraded by multistep pathway involving the formation of quinonic structure and/or tetrahydroxybenzene, catechol and/or chlorocatechol, the cleavage of aromatic ring and so on.