[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.