Characterization of Cu and Cd biosorption by Pseudomonas sp. strain DC-B3 isolated from metal mine soil

Abstract

A Cu-and Cd-resistant bacterial strain, DC-B3, was isolated from heavy metal-contaminated soils in a Cu mine, was identified as belonging to Pseudomonas sp. and biosorbed Cu 2+ and Cd 2+ from aqueous solution in the present study. Its biosorption properties as a function of environmental parameters such as contact time, initial concentration, pH, temperature and bacterial dosage were investigated through batch experiments, and the removal capacity peaked at pH 6.0, 40 °C and 0.5 g biomass L −1 at an initial concentration of 105 mg L −1 . Sorption occurred extremely rapidly at the beginning, equilibrium was reached after approximately 1 h and 4 h for Cu 2+ and Cd 2+ , respectively, and the biosorption kinetic data for both metals were well fitted by the pseudo-second-order model (r 2 > 0.99). Sorption isotherms showed that the adsorptions of both metals were highly favourable, and equilibrium data were better described by the Langmuir model (r 2 > 0.98 for Cu 2+ and 0.99 for Cd 2+ ), with the estimated maximum sorption capacities of 12.6 and 26.5 mg g −1 for Cu 2+ and Cd 2+ , respectively. Desorption assays suggested that biosorption was a chemical process and that a fraction of the metal ions might have entered the bacterial cells. Fourier transform infrared spectroscopy analysis revealed that hydroxyl, amino, carboxyl and phosphate functional groups on the bacterial cell walls might be mainly responsible for the biosorption, although their contributions to the binding of Cu 2+ and Cd 2+ were different. This result implied that the strain DC-B3 can be used as a potentially eco-friendly and efficient biosorbent for the remediation of Cu(II) and Cd(II) contaminants.

Analysis of the Genome of the Heavy Metal Resistant and Hydrocarbon-Degrading Rhizospheric Pseudomonas qingdaonensis ZCR6 Strain and Assessment of Its Plant-Growth-Promoting Traits

“…For example, a significant absorption capacity for Cd 2+ or for both Cd 2+ and Cu 2+ was observed for Pseudomonas sp. strains 375 and DC-B3, respectively [ 88 , 89 ], indicating their potential to be used as low-cost, eco-friendly, and effective treatments for the bioremediation of heavy-metal-contaminated environments.…”

Isolation and characterization of an acid and metal tolerant Enterobacter cloacae NZS strain from former mining lake in Selangor, Malaysia

“…Pseudomonas sp., strain DC-B3, was found to be resistant to copper and cadmium [32], and P. protegens strains (S4LiBe and S5LiBe) isolated from an agricultural well near a heavy metal polluted site were reportedly tolerant to 2.0 mM K 2 Cr O7 and 3.0 mM CoSO 4 , HgSO 4 , CdSO 4 .8H 2 O, and PbCl 2 [32]. In the same study [33], the reference strain Pseudomonas protegens strain CHA0 T showed poor tolerance to mercury, cadmium, plumbum, and copper, an indication that metal tolerance could be species specific. Likewise, Raoultella sp.…”

Red mud (aluminum industrial waste): An eco‐friendly treatment of electroplating effluent

“…The regeneration of adsorbent is quite crucial for the process to be cost-effective as well for the recovery of metal ions from the solution. In the present study, desorption was studied at different solution pH (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12). The result, as can be seen from Figure 6, indicates that the maximum desorption of 82.6% occurred at a pH of 8.…”

“…The batch adsorption experiments were conducted by varying several parameters, namely pH (2)(3)(4)(5)(6)(7)(8)(9)(10)(11)(12)(13)(14), temperature (20 C-50 C), adsorbent dosage (5 g/L-15 g/L), and initial Cr(VI) concentration (50 ppm-150 ppm), keeping the volume of the solution at 50 mL for every run. The solutions were agitated using a magnetic stirrer at 210 rpm.…”

“…[ 1 ] Unlike some pollutants, heavy metals cannot be degraded biologically. [ 2 ] Chromium, in general, is a heavy metal that is causing significant concern. The major industries that release chromium in their waste are electroplating, leather tanning, metal finishing, coating, textile industries, and other similar chemical industries.…”