Studies on microbiologically influenced corrosion of SS304 by a novel manganese oxidizer,Bacillus flexus

Abstract

A manganese oxidizing bacterium was isolated from the surface of steel scraps and biochemical tests and 16S rRNA sequencing analysis confirmed the isolate as Bacillus flexus. Potentiodynamic polarization curves showed ennoblement of open circuit potential, increased passive current, a lowering of breakdown potential, active re-passivation potential and enhanced cathodic current in the presence of B. flexus. Adhesion studies with B. flexus on SS304 specimens with different surface treatments demonstrated decreased adhesion on passivated and FeCl(3) treated specimens due to the removal of MnS inclusions. The present study provides evidence that surface treatment of stainless steels can reduce adhesion of this manganese oxidizing bacterium and decrease the probability of microbiologically influenced corrosion.

Effect of extracellular polymeric substances isolated fromVibrio natriegenson corrosion of carbon steel in seawater

“…MIC can accelerate the corrosion of the materials on the surfaces of ships and industrial equipment, which leads to significant security and economic concerns. [1][2][3][4][5][6] The MIC phenomenon manifests as a biofilm that grows on the surface of metals. [7][8][9] This biofilm is a complex system consisting of living and nonliving microbial cells and their metabolic products including extracellular polymeric substances (EPS) and inorganic precipitates.…”

Simul‐staining manganese oxides and microbial cells

“…Oxidized LBB has a characteristic blue color, which can be measured by spectrophotometry as a proxy for Mn(III/IV)O x concentration (Francis and Tebo 2001;Dick et al 2006). LBB has also been used as visual evidence for spot testing of microbial Mn 2+ oxidation in agar plates and microscope slide wells (Lee and Tebo 1994;Anandkumar et al 2011;Takeda et al 2012;Geszvain et al 2016). Most recently, LBB has been used to quantify reactive Mn(III) and particulate oxidized Mn at picomolar concentrations (Jones et al 2019).…”