Potential application of Staphylococcus devriesei MS as a biosorbent agent for manganase, chromium, and cadmium heavy metals in contaminated water

Abstract

Abstract This study identified one bacterial isolate as Staphylococcus devriesei, which is resistant to cadmium (Cd), manganese (Mn), and chromium (Cr) using 16S rRNA gene sequencing. Following that, the strain sequence was submitted to GenBank under accession number PQ013181. In this investigation, the biosorption potential of Staphylococcus devriesei was evaluated for the biosorption of chrmoium, cadmium, and manganese ions. The effects of pH, contact time, and initial concentration were examined in a batch-mode study. According to our findings, after 6 h at the ideal pH, Staphylococcus devriesei’s maximal biosorption capabilities of Cr and Cd were 98 and 81.2%, respectively. The maximum biosorption of Mn was 95.6% after 24 h at pH 6. SEM micrographs showed that, Staphylococcus devriesei were irregular and cracked with wrinkles on the surface after absorbing the studied Cr metal ions. It was observed that the alterations in cell size occurred when the bacterium was exposed to a dose of Mn and the aggregation of cells was seen. Bacterial cells treated with Cd exhibited irregularities, featuring depressions on their surfaces, and surface wrinkles. FTIR analysis showed obvious alterations in peak positions and intensities before and after the biosorption process. Energy dispersive X-ray analysis showed extra metal depositions on the treated cell surface compared to the control. At the ultrastructural level, TEM imaging demonstrates the involvement of extracellular and intracellular precipitates and accumulated metals on the cell walls. Thus, the results of this study indicated that Staphylococcus devriesei can effectively aid in the remediation of contaminated water with moderate to light levels of Cd, Cr, and Mn.