Biodeterioration Abilities of Microorganisms in Brake Fluids

Aims: To identify the parameters that get affected when brake fluids biodeteriorate and also to make known that brake fluids biodeteriorates into novel compounds. To also identify the organisms that deteriorates brake fluids most.
Place and Duration of Study: Department of Microbiology, University of Port Harcourt, between November 2013 and August 2014.
Methodology: Two brands of brake fluids were used (Ate and Allied). Used and Unused samples of these brake fluids were included. Microbiological analysis and physico-chemical analysis were carried out. Deterioration testing was also carried out after which gas chromatography was done to know the level of deterioration.
Results: Ate brake fluids deteriorated more than the Allied brake fluid. Biodeterioration of brake fluid is more pronounced when a mixed culture of bacteria and fungi is involved. The more the biodeterioration of the brake fluid, the lesser the pH and the higher the total viable count or the optical density. Gas chromatograms revealed that the carbon numbers shown on the peaks indicated the novel compounds the brake fluids deteriorated to. Statistical analysis using ANOVA (excel) showed that there were significant differences in the total viable counts, pH and optical densities between the mixed microbial cultures of bacteria and fungi in used Ate and used Allied brake fluids and between the mixed cultures in the used brake fluids and the unused brake fluids at P< 0.05. Significant difference was also noticed in the ANOVA readings of the viscosities of the used and unused brake fluids.
Conclusion: Brake fluid which is one of the fluids used in vehicles should be changed from time to time following the directives of the manufacturer and the idea of mixing different types of brake fluids for use in a particular vehicle should not be practiced by the owners of these automobiles.