The lipids of two strains of Lipomyces kononenkoae, grown in batch culture, were extracted and analysed. The major lipids present were phospholipids, free sterols, esterified sterols, and triacylglycerols. Phospholipid analysis indicated that phosphatidylcholine, phosphatidylethanolamine and phosphatidylinositol were the major ones. The fatty-acyt residues were C12--C18 and contained 67-74% unsaturated residues. Polyunsaturated residues accounted for 15% and 30% in L. kononenkoae CBS 2514 and L. kononenkoae CBS 5608, respectively. Analysis of the fatty-acyl residues of a low-density vesicle fraction obtained from sphaeroplasts of L. kononenkoae CBS 2514 was carried out and the results are discussed in relation to plasma membrane synthesis. The suitability of L. kononenkoae for production of single-cell protein is also discussed.
Amylases of Lipomyces kononenkoae catalyse hydrolysis of starch to a greater extent than those of other yeasts (Spencer-Martins and van Uden, 1977), making this yeast a potential source of single-cell protein production, utilising starch as substrate. To confirm this organism's suitability knowledge of its chemical composition is necessary, a major component of which is the lipid fraction. Although the lipids of L. kononenkoae have not been examined previously, those of other strains of Lipomyces have been shown to be those typical of eukaryotic micro-organisms (Erwin, 1973), namely phospholipids, sterols, esterified sterols, and triacylglycerols in L. starkeyi (Suzuki andHasegawa, 1974a) and L. lipofer (Pitryuk et al., 1975). The fatty-acyl residues have been found to contain mainly even numbers of carbon atoms (Zvyagintseva et al., 1975), predominantly C16:0 and C18:0 in L. lipoferus (Haley andJack, 1974) and L. starkeyi (Suzuki andHasegawa, 1974a), unsaturation of C18:1 residues being cis 9 (Suzuki and Hasegawa, 1974b). Haley and Jack (1974) reported that the major phospholipids of L. tipoferus are phosphatidylcholine and phosphatidylethanotamine.