Review Glycerol as a promising substrate for Yarrowia lipolytica biotechnological applications Anita Rywi  nska*, Piotr Juszczyk, Maria Wojtatowicz, Malgorzata Robak, Zbigniew Lazar, Ludwika Tomaszewska, Waldemar Rymowicz Department of Biotechnology and Food Microbiology, Wroclaw University of Environmental and Life Sciences, Chelmo nskiego 37/41, 51-630 Wroclaw, Poland article info Article history: Received 21 June 2012 Received in revised form 14 September 2012 Accepted 26 November 2012 Available online Keywords: Yarrowia lipolytica Glycerol Citric acid Pyruvic acid a-ketoglutaric acid Erythritol abstract Unconventional and nonpathogenic Yarrowia lipolytica yeast has been addressed in various studies conducted in many research centers, and in recent years has been perceived as an especially attractive host for many applications of glycerol. In its initial paragraphs, this review article provides a short characteristics of Y. lipolytica; followed by biodiesel production and brief characteristics of crude glycerol. Further on, this review summarizes relevant scientific research concerning the conversion of crude glycerol discharged after bio-diesel (fatty acid methyl/ethyl esters) manufacturing process into value-added prod- ucts through biological methods with Y. lipolytica yeast. The feasibility of using Y. lipolytica biomass, rich in proteins and oils, as food and feed additives is described as well. Subse- quently, different strategies employed to produce and improve yield and productivity of organic acids (citric, pyruvic and a-ketoglutaric acid) are presented. And, finally, the biosynthesis of new products, such as erythritol, mannitol and invertase, whose synthesis from glycerol by Y. lipolytica would be advantageous when compared with their production from common sugars, is evaluated. In conclusion, an actual wide range of compounds that can be produced from glycerol by Y. lipolytica are shown to be a valuable contribution to the development of the biodiesel industry as well as a cost-effective fermentation based on renewable resources. ª 2012 Published by Elsevier Ltd. 1. Introduction Yarrowia lipolytica yeast is physiologically very distant from Saccharomyces cerevisiae. It is taxonomically assigned to the class Hemiascomycetes and the Dipodascacea family [1]. Previously, it occurred under various names, i.e. Candida, Endomycopsis and Saccharomycopsis lipolytica [2,3]. It has long been the only known taxon in the genus Yarrowia but recently a few Candida species, including C. deformans, C. galli, C. yakushimensis nom. inval and three novel ones: Candida oslonensis sp. nov., Candida alimentaria sp. nov., and Candida hollandica sp. nov., have been proposed as new members of * Corresponding author. E-mail addresses: Anita.Rywinska@wnoz.up.wroc.pl (A. Rywi  nska), Piotr.Juszczyk@wnoz.up.wroc.pl (P. Juszczyk), maria.wojtato- wicz@wnoz.up.wroc.pl (M. Wojtatowicz), malgorzata.robak@up.wroc.pl (M. Robak), zbigniew.lazar@up.wroc.pl (Z. Lazar), ludwika. tomaszewska@gmail.com (L. Tomaszewska), Waldemar.Rymowicz@wnoz.up.wroc.pl (W. Rymowicz). Available online at www.sciencedirect.com http://www.elsevier.com/locate/biombioe biomass and bioenergy 48 (2013) 148 e166 0961-9534/$ e see front matter ª 2012 Published by Elsevier Ltd. http://dx.doi.org/10.1016/j.biombioe.2012.11.021