Removal of Lead(II) by Saccharomyces cerevisiae AUMC 3875

THE REMOVAL of lead(II) from artificial aqueous solution using live and dead biomass of Saccharomyces cerevisiae AUMC 3875 was investigated. The minimum inhibitory concentration (MIC) value of S. cerevisiae AUMC 3875 for lead(II) was 600mg/l. Maximum lead(II) uptake capacities were achieved at pH 5.0 and initial metal ion concentration 300mg/l using 3g/l live and dead cells, respectively. Maximum biosorption capacities were reached after 3h and 20min for live and dead cells, respectively. Fourier Transform Infrared spectroscopy (FTIR) results revealed the important role of C=O, ـــ OH, ـــ NH, protein amide II band,  2 PO , mannans, sulphur and sulphur-oxygen compounds in lead(II) uptake. Scanning electron microscopy analysis (SEM) showed that the cell surface morphology and surface area/volume ratio changed greatly after lead(II) uptake. Transmission electron microscopy analysis (TEM) confirmed the involvement of both extracellular adsorption and intracellular penetration through the cell wall. X-ray powder diffraction (XRD) analysis revealed the presence of Pb(SO4), Pb2OSO4 in dead yeast cells and Pb3O2(SO4),Pb2OSO4 in live biomass. Energy dispersive Xray microanalysis (EDAX) confirmed the occurrence of sulphur, oxygen and lead(II) on the cell wall. The removal of lead(II) from storage battery industry wastewater was performed by dead yeast cells efficiently.