Бактерии escherichia coli как стимулирующий фактор коррозионного разрушения стали

Microorganisms—organotrophs, which inhabit in the natural medium, negatively affect the industrial and economical metal constructions and initiate their corrosion damages. Corrosion of metals under the effect of bacteria—organotrophs—starts from their adhesion to the metal surface and formation of a biochemical structure, which is determined as a biofilm. The formation of E. coli bacteria on local fragments of low-carbon and galvanized steel during the exposure of the samples under study on a dense feeding medium inoculated by E. coli bacteria is established by scanning electron microscopy. A biofilm provides close contacting of exometabolites with the metal surface. The enhancement of corrosion on the fragments of biofilm formation is revealed. The role of exometabolites such as hydrogen peroxide and hydroxide ion, which are isolated by bacteria into the surrounding medium, in initiating the corrosion process is shown.