Single cell oil production by Lipomyces starkeyi: Biphasic fed-batch fermentation strategy providing glucose for growth and xylose for oil production

• Published in: Biochemical engineering journal 2017-05, Vol.121, p.49-58
• Main Authors: Probst, Kyle V., Vadlani, Praveen V.
• Format: Article
• Language: English
• Subjects: Fed-batch fermentation; Lipomyces starkeyi; Oleaginous yeast; Oleic acid; Single cell oil; Xylose
• ISSN: 1369-703X; 1873-295X
• DOI: 10.1016/j.bej.2017.01.015

•Different carbon sources were tested using fed-batch fermentation to produce SCO.•Lipomyces starkeyi preferred glucose for growth and xylose for oil production.•A biphasic fermentation strategy improved oil production using glucose and xylose.•An oil titer of 36.3gL−1 and an oil productivity of 0.14gL−1h−1 was achieved.•Oleic acid accounted for at least 65% of the fatty acid composition. The aim of this study was to produce single cell oil (SCO) from Lipomyces starkeyi ATCC 56304 using a biphasic fed-batch fermentation strategy. Fed-batch fermentations were performed to compare oil production using glucose, xylose, mixed-sugars (1:1 ratio of glucose:xylose), and a biphasic system supplying glucose for cell growth and xylose for oil production. The fermentation using xylose as the sole carbon source generated an oil yield of 0.16gg−1 and a productivity of 0.12gL−1h−1, two-times the oil yield (0.08gg−1) and productivity (0.06gL−1h−1) achieved with glucose. At 120h, the biphasic fermentation produced a greater oil productivity (0.13gL−1h−1) compared to the mixed-sugar fermentation (0.09gL−1h−1) but similar oil productivities (0.14gL−1h−1) were achieved for both at longer fermentation times. The biphasic fermentation generated a final oil yield of 0.17gg−1 and an oil content of 60.1% (w w−1), but oil productivity showed minor improvement at 0.14gL−1h−1 after 255h. Oleic acid accounted for at least 65% of the fatty acid content, suggesting that oil from L. starkeyi has potential for application in the biofuel and oleochemical industries.