Selection and optimization for lipid production of a newly isolated oleaginous yeast, rhodosporidium toruloides DMKU3-TK16

Abstract

Rhodosporidium toruloides DMKU3-TK16, an oleaginous yeast, was isolated from soil by an enrichment technique in nitrogen-limited medium I. Lipid production by this strain was highest in shaking flask cultivation at 150 rpm and 28°C in nitrogen-limited medium II containing per liter 70 g glucose, 0.75 g yeast extract, 0.55 g (NH4)2SO4,0.4 g KH2PO4, 2.0 g MgS047H2O, with a pH of 5.5. Under these optimal conditions, when the C/N ratio of the medium was 140, R. toruloides DMKU3-TK16 produced a lipid quantity of 9.26 g/L, which was 71.30 % of the dry biomass (13.33 g/L) after 168 h of cultivation. The major fatty acids of the cellular lipid were oleic acid (41.54%), palmitic acid (22.49%), linoleic acid (15.12%) and steric acid (14.56%).