Bionanomining of copper-based nanoparticles using pre-processed mine tailings as the precursor

Rhodococcus erythropolis ATCC 4277 behavior against different metals and its potential use in waste biomining

“…Although R. erythropolis is known to be adaptable and intrinsically resistant in copper environments, by the ubiquitous and constitutive expression of multicopper oxidases like copper tolerance protein -CueO RE -, when Cu is present in nanoparticle format, they perform an antibacterial role, potentialized on aqueous medium [47,48]. In a previous study, this research group demonstrated the biomining of chalcopyrite ore waste using R. erythropolis ATCC 4277 solubilized Cu in nanoparticle form [45]. As we used the same conditions described in the study above it is natural that Cu nanoparticles were present in the biomining solution and partially inhibited R. erythropolis ATCC 4277 growth, due to its antimicrobial potential.…”

“…After 48 h of process, the copper in the bulk solution was about 250 mg.L -1 , totalizing 9.23 mg of Cu per g of tailing ore, representing 38% of Cu recovery. Notably, the bioleaching process used chalcopyrite (CuFeS 2 ) as mineral feedstock, which is known in the biomining eld as hard to leach because of its characteristic passivation layer formation, despite its copper sul de secondary ores concentration [3,45].…”

“…After all, the use of R. erythropolis in this bioprocess is still incipient and a promising approach. So far, literature shows that R. erythropolis ATCC 4277 strain demonstrated the potential to grow and adsorb copper in low-grade ore environments and to synthesize copper or iron nanoparticles from chalcopyrite and coal tailings, respectively [44,45]. These characteristics point to a microorganism that can be employed in the biomining process with feasibility, but information about bacterial behavior throughout time in metal is necessary.…”