Background: The bioremediation of soils impacted by diesel fuels is very often limited by the lack of indigenous
microflora with the required broad substrate specificity. In such cases, the soil inoculation with cultures with the
desired catabolic capabilities (bioaugmentation) is an essential option. The use of consortia of microorganisms
obtained from rich sources of microbes (e.g., sludges, composts, manure) via enrichment (i.e., serial growth
transfers) on the polluting hydrocarbons would provide bioremediation enhancements more robust and
reproducible than those achieved with specialized pure cultures or tailored combinations (co-cultures) of them,
together with none or minor risks of soil loading with unrelated or pathogenic allocthonous microorganisms.