Extraction of Lipids from Yarrowia Lipolytica

JUAN MANUEL MILANESIO; YAOCIHUATL MEDINA-GONZÁLEZ; SÉVERINE CAMY; JEAN-STÉPHANE CONDORET

La Haya

Encuentro; 13th European Meeting on Supercritical Fluids; 2011

ISASF

A major sector of lipid biotechnology focuses on the ability of oleaginous microorganisms to convert various natural substances into reserve lipids. These lipids are mainly triacylglycerols and steryl esters. The yeast Yarrowia lipolytica is a high lipid-content yeast. In the present work, supercritical carbon dioxide (SCCO2) lipid extractions from Y. lipolytica, using ethanol as a co-solvent, were performed. To better assess the supercritical extraction yield, high pressure phase boundaries in the systems ‘CO2 + yeast oil’ and ‘CO2 + ethanol + yeast oil’ were determined. It was found that a maximum concentration of 10 g of oil / kg of solvent could be dissolved with pure CO2. The addition of ethanol to the solvent mixture increased this value. It is shown that the oil solubility increases with the pressure at a given temperature. SCCO2 can be used to extract neutral lipids, as triacylglycerols. The addition of the ethanol also allows a more efficient extraction of triacylglycerols and also an extraction-fractionation of other lipids as phospholipids. Different pretreatments are necessary to obtain good extraction yields. The best performance was obtained for the ethanol macerated yeast. The ethanol maceration of the yeast was shown to modify the matrix, allowing the extraction of bonded lipids.