| Abstrakt: |
Yarrowia lipolytica is a unique, strictly aerobic yeast with the ability to degrade efficiently hydrophobic substrates. In the present work, we evaluated the degrading potential of Yarrowia lipolytica IMUFRJ 50682, isolated from tropical estuarine water in Rio de Janeiro (Brazil), and the possible biomolecules produced during this process. To investigate which crude oil compounds are degraded by Y. lipolytica IMUFRJ 50682, this microorganism was grown in a medium containing Marlim petroleum (19 °API, American Petroleum Institute gravity) at 28 °C and 160 rpm for 5 days. The residual petroleum was submitted to gas chromatograph-mass spectrometric analysis (GC-MS). The chromatographic fingerprints of the residual petroleum were compared with the abiotic control test incubated in the same conditions. Y. lipolytica assimilates high molecular weight hydrocarbons, such as n-alkanes (C11-C19), isoprenoids (pristane and phytane), aromatics with two or three aromatics rings (naphthalene, methylnaphthalenes, dimethylnaphthalenes, trimethylnaphthalenes, phenanthrene, methylphenanthrenes, dimethylphenanthrenes, anthracene). This strain was also capable of consuming more complex hydrocarbons, such as tricyclic terpanes. During this biodegradation, the emulsification index of the culture medium increased significantly, showing that biosurfactant molecules can be produced from this process. Therefore, Y. lipolytica IMUFRJ 50682 showed to be a potential crude oil degrading yeast, which can be used for bioremediation processes and simultaneously produce bioproducts of commercial interest. [ABSTRACT FROM AUTHOR] |
