Distribution, characteristics of extracellular polymeric substances of Phanerochaete chrysosporium under lead ion stress and the influence on Pb removal

Abstract

The distribution, characteristics of extracellular polymeric substances (EPS) of Phanerochaete chrysosporium under Pb2+ stress and the influence on Pb removal were investigated. Polysaccharides was found to be the main composition in both soluble EPS (SEPS) and bounded EPS (BEPS). More polysaccharides and protein in BEPS were detected with the increased Pb2+ concentration. The ratio of Pb amount distributed in BEPS to the total Pb removed by the fungal biomass gradually decreased from 91.66 to 61.27% in group with 50 mg/L of initial Pb2+, but kept at about 35% or 25% in groups with higher Pb2+. It implies that BEPS played a certain role in the lead removal process, and the role of BEPS was relatively more important in the removal of lower concentration of Pb2+ and in the initial period of Pb removal. With FTIR analysis and Pb2+ adsorption experiment, more effective functional groups and better Pb2+ adsorption capacity was demonstrated in BEPS than in SEPS. SEM–EDS analysis demonstrated that part of Pb immobilized in BEPS was in the form of Pb precipitation. The increased molecular weight in SEPS and more polysaccharides in BEPS were probably beneficial for the adhesion of Pb precipitation.

Layers of Uranium Phosphate Nanorods and Nanoplates Encrusted on Fungus <i>Cladosporium</i> sp. Strain F1 Hyphae

“…Differences in the adsorption capacity of the two fungi to the negatively charged layers of pre-synthesized uranyl hydrogen phosphate hydrates may be explained by the total interaction energy, which is calculated by the repulsive electrostatic force and attractive van der Waals force ( Pajerski et al , 2019 ). These physicochemical parameters are attributed to the different physical and chemical structures of the cell wall and different amounts of extruded EPSs, which also offer many different functional groups, such as carboxyl, hydroxyl, sulphate, phosphate, and amino groups in varying degrees ( Yin et al , 2011 ; Chen et al , 2013 ; Li et al , 2020 ). Therefore, as shown in Table 1 and 2, the purified EPSs of Cladosporium sp.…”

Comparative Copper Resistance Strategies of Rhodonia placenta and Phanerochaete chrysosporium in a Copper/Azole-Treated Wood Microcosm

“…The existence of mucilaginous sheaths around hyphae can also provide a matrix for fungus–mineral interactions and metal transformations harbouring mineral-weathering and metal-chelating agents. Accordingly, the extracellular polymeric substances (EPS) of P. chrysosporium were shown to contribute to Pb stress resistance by Pb immobilization [ 58 , 59 ]. Metal diffusion and the precipitation of metal oxalates that occur in this well-hydrated mucilaginous microenvironment were successfully observed using the wet-mode environmental SEM (ESEM) technique [ 60 ].…”

Adsorption Properties of Pb2+ by Ferric Hydroxide Loaded White Rot Fungi

“…When pH value is 6, the adsorption rate reaches the maximum value of 94.58%, the adsorption capacity is 181.36mg /g, and the adsorption rate gradually flattens when pH value is 8-10. When pH is less than 5, lead ions mainly exist in the form of Pb 2+ and Pb(OH) + in aqueous solution [13]. In this case, there may be electrostatic repulsion between iron oxides on the surface of white rot fungi and Pb 2+ in the solution, and there may be competitive adsorption sites between H + and Pb 2+ [14].…”