Determination of bacterial intracellular and extracellular biotransformation compounds and biodegradation of kerosene based industrial rolling oils via gas chromatography-mass spectrometry

Abstract

In the aluminum and steel industry there is no specialized bioremediation of the pure or spent hydrocarbon rolling oils. Hazardous waste management companies remove the spent oils which eventually end up being dumped at local hazardous material dump sites. The lack of an environmentally friendly strategy to reduce the hazardous waste from factories was incentive for this research. The aim was to determine and monitor an indigenous Achromobacter aegrifaciens bacterial biotransformation/biodegradation of Kerosene based rolling oils including the additives: methyl laurate, lauric acid and Shellsol D100. This was done via dehydrogenase assays and Gas Chromatography-Mass Spectrometry. Achromobacter aegrifaciens bacterial biotransformation was also compared to that of an exogenous consortium of Lysinibacillus fusiformis and Pseudomonas synaxantha. Results were analyzed statistically, using SPSS version 24. The mean differences were significant at the 0.05 level for both DHA and GCMS. Further, subterminal oxidation was determined to be the main activation mechanism for the biotransformation. Methylation occurred during rolling oil biotransformation but was more prevalent in biotransformations of the additives, especially methyl laurate. Methylation resulted in less efficient biotransformations compared to subterminal oxidation. This bioremediation strategy can now be further established for larger volume bioreactors as we established that the toxic monoaromatic compounds were successfully degraded at the end of five weeks making this bioremediation strategy a viable alternative to the current dumping by waste companies.