Bio-contamination is one of the main sources of contamination of jet fuel and aircraft fuel systems, causing plugging, clogging of flow in fluids systems and, particularly, microbiologically influenced corrosion (MIC) of fuel tanks. Antimicrobial and/or antibiofilm coatings and materials are a highly promising tool to anticipate and mitigate bio-contamination. These materials and coatings should be robust to severe bio-contamination while at the same time have no reverse effect on the fuel itself.
Therefore, there is an urgent need to update protocols enabling the development, testing and validation of antimicrobial in simulated environment representative of real aircraft conditions.
The MICTEST project has as main goal to develop new exposure protocols for testing and validation of coatings, materials and components of aircraft fuel systems at laboratory environment, validate the different protocols for microbial growth inhibition and material and coating performance in pilot fuel tanks.
Conclusions:
Firstly, a microbial strain collection (142 strains) was obtained from fuel tanks sample (CLH facility). From those, ten strains have been selected following two criteria: i) belonging to OTUs from the core microbiome and ii) belonging to genera defined in literature as problematic for fuel systems. Finally, a three-strain consortium comprehended by a fungal strain (genus Hormoconis), and two bacterial strains (genera Pseudomonas and Escherichia) has been selected. The ability to form a synergistic multispecies biofilm on the surface of a representative material of aircraft fuel tanks was optimized and tested at lab-scale, simulating real environmental conditions, and monitored through plate count and Scanning Electron Microscope (SEM). All the obtained information allowed the creation of a protocol design in guideline format with the aim of standardized antimicrobial/antibiofilm material properties studies. In conclusion, different methodologies described in this project can contribute to validate new materials, coatings, fuels and components for aviation systems.