The mitochondria of baker’s yeast (obtained as the end-product of industrial production) and bottom-fermenting brewer’s yeast (obtained at the end of propagation in industrial beer production) were analysed in this work. It was determined that the main phospholipid of baker’s yeast mitochondria was phosphatidylcholine, accounting for more than 47% of total phospholipids, followed by phosphatidylethanolamine, phosphatidylinositol and cardiolipin. In the neutral lipid composition, ergosterol was the main component, accounting for 0.039 mg/mg proteins. The fatty acid composition was characterised by high predominance of monounsaturated fatty acids (79%). In the mitochondria of brewer’s yeast, the phospholipid classes were almost evenly represented accounting between 23 and 16%. Ergosterol was the main neutral lipid accounting for 0.016 mg/mg protein, but significant amount of squalene was also determined (0.007 mg/mg proteins) despite the aerobic conditions. Fatty acid composition was characterised by small predominance of unsaturated acids (55%) and high predominance of C16-acids (69%). The results led to the conclusion that estimation of the lipid composition of industrial yeasts based on the results obtained in laboratory conditions is uncertain and that the analysis of the yeast grown in specific conditions should be performed.
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