Effect of different C/N ratios on carotenoid and lipid production by Rhodotorula glutinis
- 1.4k Downloads
Due to the increasing demand for sustainable biofuels, microbial oils as feedstock for the transesterification into biodiesel have gained scientific and commercial interest. Also, microbial carotenoids have a considerable market potential as natural colorants. The carbon to nitrogen (C/N) ratio of the respective cultivation media is one of the most important parameters that influence the production of microbial lipids and carotenoids. Thus, in the present experiment, the influence of different C/N ratios, initial glucose loadings, and ammonium concentrations of the cultivation medium on microbial cell growth and lipid and carotenoid production by the oleaginous red yeast Rhodotorula glutinis has been assessed. As a general trend, both lipid and carotenoid production increased at high C/N ratios. It was shown that not only the final C/N ratio but also the respectively applied initial carbon and nitrogen contents influenced the observed parameters. The lipid yield was not affected by different ammonium contents, while the carotenoid production significantly decreased both at low and high levels of ammonium supply. A glucose-based increase from C/N 70 to 120 did not lead to an increased lipid production, while carotenoid synthesis was positively affected. Generally, it can be asserted that lipid and carotenoid synthesis are stimulated at higher C/N ratios.
KeywordsMicrobial lipid Microbial carotenoid Rhodotorula glutinis C/N ratio
- EU (2009) Directive 2009/28/EC of the European Parliament and of the council of 23 April 2009 on the promotion of the use of energy from renewable sources and amending and subsequently repealing Directives 2001/77/EC and 2003/30/EC. Off J European Union L140/16Google Scholar
- Latha BV, Jeevaratnam K, Murali HS, Manja KS (2005) Influence of growth factors in carotenoid pigmentation of Rhodotorula glutinis DFR-PDY from natural source. Indian J Biotechnol 4:353–357Google Scholar
- Saenge C, Cheirslip B, Suksaroge TT, Bourtoom T (2011) Efficient concomitant production of lipids and carotenoids by oleaginous red yeast Rhodotorula glutinis cultured in palm oil mill effluent and application of lipids for biodiesel production. Biotechnol Bioprocess Eng 16:23–33CrossRefGoogle Scholar