Yarrowia lipolytica: A model microorganism used for the production of tailor‐made lipids

Abstract

This paper presents a review of studies related with the production of specialty lipids by the yeast Yarrowia lipolytica during growth on various fatty agro-industrial residues utilized as substrates. In a first approach, the potential for growth on stearin (a low-cost industrial derivative of tallow composed of saturated free fatty acids) was assessed; significant biomass production was obtained, accompanied by notable intracellular accumulation of lipid which occurred as a primary anabolic activity regardless of the extracellular nitrogen availability in the medium. Y. lipolytica consumed its own storage lipids in the stationary growth phase. The secretion of extracellular lipase in non-negligible quantities was also observed in cultures performed on stearin. Although Y. lipolytica tended to increase the intracellular level of stearic acid, its reserve lipid could be used as a cocoa butter substitute, provided that an oleic acid donor, such as chemically hydrolyzed rapeseed oil, is used as co-substrate together with stearin. Accordingly, predetermined lipids with composition similarities to cocoa butter were synthesized using low-cost substrates. Other strategies related with the production of microbial cocoa butter substitutes are also presented and comprehensively discussed.

Cocoa-Butter-Equivalent Production from <i>Yarrowia lipolytica</i> by Optimization of Fermentation Technology

“…Due to regional diversity and climate differences, the composition of saturated fatty acid in cocoa butter is a little different, from 55 to 67% (w/w). An average fatty acid composition of saturated fatty acid is as follows: Stearic acid is 32-37%, oleic acid is 30-37%, palmitic acid is 23-30% and linoleic acid is 2-4% (Lipp and Anklam, 1998;Papanikolaou and Aggelis, 2010;Ratledge, 1994).…”

“…One common industrial applications of yeast lipid is to synthesize microbial substitutes of cocoa butter (Papanikolaou and Aggelis, 2010;Ratledge and Wynn, 2002). These microorganisms reserve their lipids mostly in the form of Triglycerides (TAGs) esterified in the Sn-2 position by unsaturated fatty acids (Ratledge, 1994).…”

“…Since oleaginous yeasts can accumulate unsaturated fatty acids more than 65% (w/w) of the total lipids but cocoa butter contains saturated lipid (palmitic and stearic acid) more than 60% (w/w) (Ratledge, 1994). Hence, the main problem to solve is how to increase the level of total saturated fatty acids inside the yeast cells specially the content of C18:0 (Lipp and Anklam, 1998;Papanikolaou and Aggelis, 2010;Ratledge and Wynn, 2002). Numerous strategies have been explored to the increase of Saturated Fatty Acids (SFA), such as the genetic manipulation of oleaginous yeast (Ykema, 1989), inhibition of ∆ 9 and ∆ 12 dehydrogenase (Moreton, 1985), cultivation of yeasts on low-oxygenated media (Davies et al, 1990) and addition of stearic acid or derivative into the medium (Papanikolaou et al, 2001).…”

NITROGEN SOURCES ON TPOMW VALORIZATION THROUGH SOLID STATE FERMENTATION PERFORMED BY Yarrowia lipolytica

“…Y. lipolytica is used now as a model organism for several academic studies, making this dimorphic yeast significant for biotechnological applications. Properties like intracellular accumulation of oil, secretion of large amounts of organic acids, high capacity for enzyme secretion and its acceptance as generally recognized as safe (GRAS) focus the interest on this yeast as a potential producer of basic commodities (Barth and Gaillardin, 1997;Papanikolaou and Aggelis, 2010).…”

Microbial lipid production by Rhodosporidium toruloides under sulfate-limited conditions

“…Microbial lipid has already been developed as sources of high-valued oils including cocoa butter equivalent (CBE) and polyunsaturated fatty acids (Papanikolaou and Aggelis, 2010;Ratledge and Wynn, 2002). Very recently, it has also been suggested as a potential feedstock for biodiesel industry (Adamczak et al, 2009;Easterling et al, 2009;Li et al, 2008;Vicente et al, 2010), because microbial lipid can be produced using various cheap feedstocks, especially renewable biomaterials such as lignocelluloses.…”