Characterization of biosurfactants enhancing kerosene degradation

Aydin, Dilan Camille
İçgen, Bülent
Keroseneis a colorlessflammable hydrocarbon liquidandit is obtained from the fractional distillation of petroleum[1]. Ithas numerous applicationsas fuel for jet engines, heating oil, solvent andinsecticide[2].Because ofgrowing needs of kerosene production and extensive usage may endup with surface water contamination.Due to its hightoxicity to biota, kerosene contaminationrequires remedial action to reduce environmental damage[3].Biodegradation is an effective and eco-friendly methodperformedbyhydrocarbondegrading bacteria.Some ofhydrocarbon degrading bacteria have the ability toproduce extracellular compounds called biosurfactants.Based on their diverse chemical structures,biosurfactants are classified as glycolipids, lipopeptides, phospholipids, fatty acids, neutral lipids, and polysaccharide–protein complexes [4]. Biosurfactants can reducesurface tension and emulsify hydrocarbonsbyenhancingthebioavailability. They also have advantages over chemicalsurfactants byhaving low toxicity, being biodegradable[5]and efficient even at extreme temperature or pHconditions[6].Therefore, characterization of biosurfactants produced by hydrocarbon degraders is of great interest especially in environmental applications [4].This study aimed at determining biosurfactants produced bykerosene degraders. Therefore, previously determined 19 kerosene degraders were primarily screened for their biosurfactant productivity against kerosene. In order to characterizethe type of biosurfactant; Phenol-H2SO4, Biuret, Phosphate and CTAB/Methylene Blue Agar Plate testswere performed.All the isolatesshowedpositive responsestoCTAB/Methylene Blue Agar Plate test, confirming the production rhamnolipid biosurfactants[7]. These results were also justified withFourier Transform Infrared (FTIR) Spectroscopy.