Evaluation of lipid biosynthesis ability by Rhodotorula and Sporobolomyces strains in medium with glycerol

Single cell oils (SCO) can be a source of nutritionally valuable fatty acids and raw material in biodiesel production. Among the oleaginous yeasts, those which additionally generate carotenoid pigments are beneficially distinguished. Rhodotorula and Sporobolomyces strains were screened for the ability to grow and produce intracellular lipids in medium containing pure glycerol. In this paper, we verified that glycerol is unfavorable carbon source for a strain of S. salmonicolor and a good source of carbon for the growth and increases lipids content in the biomass of examined Rhodotorula yeast compared to glucose. The best volumetric efficiency of lipids biosynthesis (4.73 g L-1) in the medium with glycerol showed R. glutinis var. rubescens LOCKR13. In all investigated strains, oleic acid had the highest proportion of the total fatty acids. Nutritionally beneficial features were demonstrated by R. mucilaginosa, strain ATCC 66034 containing docosapentaenoic acid and reaching a high lipids biosynthesis efficiency (3.24 g L-1). Compared to glucose after incubation of R. aurantiaca, R. glutinis, R. gracilis and R. mucilaginosa strains with glycerol, the higher PUFA content per unit volume of medium was observed.