Lipid production by Rhodosporidium toruloides Y4 using different substrate feeding strategies

Abstract

Microbial lipid is a potential alternative feedstock for the biodiesel industry. New culture strategies remain to be developed to improve the economics of microbial lipid technology. This work describes lipid production by the oleaginous yeast Rhodosporidium toruloides Y4 using a 15-l bioreactor with diVerent substrate feeding strategies. Among these strategies, the intermittent feeding mode gave a lipid productivity of 0.36 g l ¡1 h ¡1 , whereas the constant glucose concentration II (CC-II) mode gave the highest lipid productivity of 0.57 g l ¡1 h ¡1 . The repeated fed-batch mode according to the CC-II mode was performed with a duration time of 358 h, and the overall lipid productivity was 0.55 g l ¡1 h ¡1 . Our results suggested that substrate feeding modes had a great impact on lipid productivity and that the repeated fed-batch process was the most appealing method by which to enhance microbial lipid production.

Retracted Article: Oleaginous yeast-based production of microbial oil from volatile fatty acids obtained by anaerobic digestion of red algae (Gelidium amansii)

“…A similar phenomenon has been previously observed in another study [29], which also used a repeat batch process for microbial lipid production. To explain this phenomenon, the profile of VFA consumption, TN (Total nitrogen), TOC (Total organic carbon), and C/N (Carbon/Nitrogen) ratio were also measured.…”

Kinetics of continuous cultivation of the oleaginous yeast Rhodosporidium toruloides

“…Very high lipid content was obtained when it was cultivated in media with an initial carbon-to-nitrogen (C/N) ratio of 77 (Turcotte and Kosaric, 1989). We demonstrated that high lipid titer could be achieved by fed-batch and repeated fed-batch culture of R. toruloides under nitrogen limitation conditions (Li et al, 2007;Zhao et al, 2010). During the cultivation process, cell growth was accompanied with lipid accumulation.…”

New Frontiers in the Production of Biodiesel: Biodiesel Derived from Macro and Microorganisms

“…While the ratio C/N plays the most important role in lipid accumulation, the culture mode is also of special interest. For this reason, Zhao et al (2011) used different feeding strategies with yeast R toruloides Y4 and concluded that the fed-batch strategy exhibited the largest oil accumulation potential under large-scale production plant, while keeping the residual glucose concentration to 5 g/L of carbon source and the fed-batch cycles were multiple times repeated. Authors removed the majority of the mature culture at the end of each cycle, keeping 900 ml of the culture in the bioreactor.…”