Inhibition or acceleration: Bacterial test media can determine the course of microbiologically influenced corrosion

The objective of this study was to determine the effect of different test media on the initial attachment of Escherichia coli and subsequent corrosion of carbon steel coupons. Nutrient broth (NB) and minimal media (MM) with different carbon sources and phosphate concentrations were used. The initial bacterial attachment to the coupons increased with time in all of the studied media. Longer term immersion studies showed accelerated corrosion of steel coupons in all inoculated MM, whereas corrosion inhibition was observed in inoculated NB. The results showed that the test medium can play a critical role in determining the outcome of microbiologically influenced corrosion tests.