Rhodosporıdıum toruloıdes Y27012 ile tek hücre yağı üretiminde farklı ortam koşullarının etkisi

Abstract

In this study, an oleaginous yeast strain, Rhodosporidium toruloides Y27012 was used for the production of single cell oil (SCO) using a cultivation medium containing glucose (control), beet molasses, malt extract as carbon source and NH4Cl (control), yeast extract, pepton as nitrogen sources. The results showed that optimum lipid yield for carbon and nitrogen sources were 3,26 g/L with beet molasses and 3,34 g/L with peptone, respectively.To achieve a higher SCO yield, different oils like linseed, sesame, canola, trout and borage oil were added to the lipid production medium, resulting in an increase of SCO from 3,23 to 7,39 g/L with linseed oil. High concentrations of EPA and DHA were obtained in culture containing trout oil. Gas chromatographic analysis of the synthesized microbial lipids revealed that the most important fatty acids, such as oleic acid, linoleic acid, ALA, EPA, DHA, can be produced by adding oils. Lipid extraction process from yeast biomass and its efficiency represent an important key step in the process of SCO production. So it is essential to find an efficient extraction method to increase the lipid yield. In this work, ultrasound-assisted extraction method was used to investigate its effects on the yield of lipid from R.toruloides Ultrasonication dramatically enhanced the extraction of lipid. The cellular total lipid was obtained by extraction with chloroform?methanol (2:1, v/v). The fatty acid compositions of the total lipid samples were analyzed as their methyl esters by ThermoQuest Trace GC 2000 gas chromatography using a published procedure.