Effects of selected ionic liquids on lipid production by the oleaginous yeast Rhodosporidium toruloides

• Published in: Bioresource technology Vol. 130; pp. 339 - 344
• Main Authors: Huang, Qitian, Wang, Qian, Gong, Zhiwei, Jin, Guojie, Shen, Hongwei, Xiao, Shan, Xie, Haibo, Ye, Shuhong, Wang, Jihui, Zhao, Zongbao K.
• Format: Journal Article
• Language: English
• Published: Kidlington Elsevier Ltd 01-02-2013; Elsevier
• Subjects: Biofuel; Biofuel production; Biofuels; Biological and medical sciences; Biomass; Biotechnology; Culture; Energy; Fundamental and applied biological sciences. Psychology; Industrial applications and implications. Economical aspects; Inhibition; Ionic liquids; Ionic Liquids - toxicity; Lignocellulose; Lipid Metabolism; Lipid production; Lipids; Microbial lipid; Rhodosporidium toruloides; Yeast; Yeasts - drug effects; Yeasts - growth & development; Yeasts - metabolism; Ionic liquids; Lipid production; Biofuel; Microbial lipid; Rhodosporidium toruloides; Fungi; Oil; Yeast; Lipids; Microorganism; Basidiomycota; Ionic liquid
• ISSN: 0960-8524; 1873-2976
• DOI: 10.1016/j.biortech.2012.12.022

► Oleaginous yeast R. toruloides tolerated ionic liquids used for biomass pretreatment. ► Assimilation of the anion of [Emim][OAc] led to a rapid alkaline-pH shift. ► Ionic liquids tended to increase saturated fatty acids contents of lipid samples.
Lignocellulosic biomass pretreatment with ionic liquids (ILs) has been emerged as a new technology, but the effects of residual ILs on the downstream biotransformation remain largely unknown. Here, three typical ILs were tested for their effects on lipid production by the oleaginous yeast Rhodosporidium toruloides AS 2.1389. When cultures were maintained at pH 6.0 in the presence of 30mM ILs, [Emim]Cl, [Emim][DEP], or [Emim][OAc], minor inhibition effects were observed. When cultures were performed in the presence of 60mM ILs or without pH control, inhibition was largely dependent on ILs. Detailed analysis indicated that the anion of [Emim][OAc] was assimilated, leading to a rapid alkaline-pH shift and enhanced inhibition on cell growth and lipid production. Our results demonstrated that R. toruloides is a robust lipid producer tolerating ILs at low concentrations, and that care should be taken in bioprocess control and data analysis when ILs are involved.