Fuels may often seem unlikely substances to suffer from microbial spoilage, but some types of microorganisms grow in fuel and can cause degradation. Microbial contamination of fuels can have serious economic consequences. Examples range from a drop in product quality to serious compromises to equipment performance (which can also lead to accidents).
There are also environmental risks. The microbial degradation of gasoline on soil was found in one study to result in the loss of the alkane fraction within 15 days. Alkanes degraded most quickly on soil leading to pollution.
In contrast, when the appropriate microorganisms are cultured, the use of microorganisms can help to address environmental problem caused by fuel leaks, such as oil spills.
Biodegradation of a hydrocarbon contamination by microorganisms can be one of the cheapest contaminant removal options. The downsides of this approach relates to the time required especially in extreme environments, given the invariably non-optimal hot or cold air temperatures.
The task of assessing fuel to ensure that it is free from microorganisms in sufficient numbers that can cause degradation is difficult. However, detection and quantification of microorganisms are critical in monitoring fuel systems for an early detection of microbial contaminations.
Looking for ways to improve detection, researchers from Institute of Plant Science and Microbiology, University of Hamburg, Hamburg, Germany analyzed six metagenomes, one transcriptome, and more than 1,200 fluid and swab samples taken from fuel tanks or kerosene.
By conducting advanced identification methods based on deep metagenome sequencing the research discovered a metabolic symbiosis between fungi and bacteria. From this, the researchers uncovered a high number of genes related to kerosene degradation and biofilm formation.
The research also found that the common remediation methods designed to protect fuels from microbial contamination, such as polymeric coatings, designed to prevent contact of the underlying materials with corrosive media and microorganisms, are actually susceptible to microbial degradation after formation of microbial biofilms on the surfaces of the coating materials.
With the core research, understanding how bacteria and fungi interact is the fist step on the path for improved detection and novel treatments to address biofouling of fuels. It is of particular concern that certain metabolites generated by fungi that can grow in and metabolize fuel, like formic, citric, and acetic acids, serve to be damaging to metals, glass, masonry, and other materials and therefore contribute to corrosion and significant damage.
The research appears in the journal Frontiers in Microbiology, titled “Deep (Meta)genomics and (Meta)transcriptome Analyses of Fungal and Bacteria Consortia From Aircraft Tanks and Kerosene Identify Key Genes in Fuel and Tank Corrosion.”
