The performance of Hura crepitans mediated Ag (silver) nanoparticle material on the inhibition of microbes (including six bacteria and a fungus strain) inducing microbiologically-influenced-corrosion (MIC) of metals was investigated in this paper. Leaf-extract was obtained from the Hura crepitans for use as a precursor for the Ag-nanoparticle synthesis, which was then characterised by the instrumentation of scanning electron microscopy and energy dispersive spectroscopy (SEM+EDS). The natural plant-mediated Ag-nanoparticle material was then utilised for sensitivity and/or resistance experimental investigations against three Gram-positive and three Gram-negative bacteria and a fungus strains of microbes that are known to induce microbiologically-influenced-corrosion in metallic materials. From this, the inhibition of microbial growth by the plant-extract mediated Ag-nanoparticle was compared with that from a commercial antibiotic that was used as the control. From the results, it was established that all the microbial strains studied were sensitive to the Hura crepitans mediated Ag- nanoparticle material while three out of the seven microbial strains for the study were resistant to the control antibiotic chemical. The implications and recommendations, ensuing from these results, on the use of the bio-mediated Ag-nanoparticle in MIC mitigation/control applications are detailed in the study.
Microbiologically-influenced-corrosion (MIC) is capable of enhancing all the eight basic forms of corrosion mechanisms including uniform/general corrosion, galvanic corrosion, pitting corrosion, intergranular corrosion, corrosion by selective leaching, erosion corrosion and stress corrosion.1-4 Through any form of these attacks on metallic materials, insidious damages are perpetrated, especially in material holding vessels or material conveying pipelines. MIC attacks can be high in corrosion rates but could still exhibit low likelihood of detection and therefore high likelihood of catastrophic failure in many industrial systems including chemical, food processing and energy sectors (i.e. nuclear power/oil and gas facilities).2-3,5-8 Among these, the menace of MIC in oil and gas exploration is attracting attention globally due to the attendant huge costs that run into billions of US$ in many countries.5-7 The dire needs to reduce these costs and avert other environmental consequences such as hazards to ecosystems from MIC induced oil spillage are making researchers and stakeholders seek for solution approach for mitigating MIC.8-10