Continuous Cultivations of the Oleaginous Yeast Lipomyces starkeyi

Abstract

Oleaginous yeasts are microbial factories capable of converting carbohydrates into lipids. The transesterification of these lipids results in the production of biodiesel. The oleaginous yeast Lipomyces starkeyi is an excellent lipid producer. To attain parameters for the understanding of the lipid production process, we performed continuous cultivations using glucose and xylose as carbon sources. The highest overall cell yield of 0.443 g/g and lipid yield of 0.236 g/g was observed at the dilution rate of 0.03 h -1 while the highest cell and lipid productivities were obtained at 0.06 h -1 . Gas chromatography analysis of the esterified lipids indicated that the major constituents of this complex are palmitic acid, stearic acid, oleic acid, and linoleic acid with an estimated cetane number (approximately 61) similar to that of palm biodiesel, which is important for biofuel production. These data should be very helpful to develop and design more efficient bioprocesses for microbial lipid production. Palavras-chave: oleaginous yeast, dilution rate, biodiesel. Universidade Estadual de Londrina -Rodovia Celso Garcia Cid, Pr 445, Km 380 -Campus Universitário Caixa Postal 10.011 CEP 86057-970 Centro de Ciências Exatas -Departamento de Bioquímica e Biotecnologia Fone +55 (43) 3371.4270 -biq@uel.br Universidade Estadual de Londrina -Rodovia Celso Garcia Cid, Pr 445, Km 380 -Campus Universitário Caixa Postal 10.011 CEP 86057-970 Centro de Ciências Exatas -Departamento de Bioquímica e Biotecnologia Fone +55 (43) 3371.4270 -biq@uel.brmechanism underlying the assimilation of these sugars is crucial for the further development of this industrial process.