[Extracellular polymeric substances (EPS) of white-rot fungus and their effects on Pb2+ adsorption by biomass].

The extracellular polymeric substances(EPS) of P.chrysosporium and their effects on Pb2 + biosorption were studied.The product,composition of EPS and the effects on Pb2 + biosorption capacity were investigated in lab via flask experiments.The surface changes of mycelium before and after EPS extraction,before and after Pb2 + adsorption were researched by environment scanning electron microscope with energy-dispersive X-ray analysis(ESEM-EDX).Results showed that at 113 h,the maximum yield of EPS was 125.5 mg /L,which contained 46.6%-54.3% of sugar and 31.2%-35.1% of protein.The results of control test after EPS extraction displayed a decrease of biosorption capacity of Pb2 + among 2.12 mg /g(113 h)-7.73 mg /g(41 h).The results of environment scanning electron microscope(ESEM) showed that the EPS extraction affected the cell wall of white-rot fungus and the Pb-contained globular particle after Pb2 + uptake,which was very useful for further study on heavy metal biosorption mechanism.